Keysight 3000T scope 1 GHz(or more) hardware upgrade mod

[TheSteve]

My Keysight MSOX3024T was born with 200 MHz of bandwidth, it now has 1 GHz.

There have been plans in the works to upgrade a 3000T series scope to 1 GHz for a while. The 1 GHz upgrade follows in the footsteps of the 3000A series 500 MHz upgrade found here - https://www.eevblog.com/forum/testgear/dsox2000-and-3000-series-licence-have-anyone-tried-to-hack-that-scope/msg987126/#msg987126

Here are the main points of interest regarding the upgrade:

#1 - This upgrade only applies the "T" series as the 500 MHz and below 3000A series scopes have a different PCB that cannot be populated with the required parts
#2 - I think I was borderline crazy to perform this upgrade as there were quite a few unknowns. Parts list or not think long and hard before attempting this as a 3000T series scope is far from cheap and you'll lose any/all calibration and warranty on it. My scope channels didn't work on the first few attempts as every part that needed to be swapped was not known.
#3 - The mod requires installing/replacing/removing 168 components, the smallest being 0402 in size.
#4 - You will need decent soldering/rework gear and skills to perform the mod and should have a hot air station
#5 - I was able to purchase all of the needed parts for under $200.00 USD including shipping/taxes
#6 - There are no modifications to the firmware to perform this mod, no changes or patches to the flash memory are needed and
there are no hacked licenses etc. You don't require a network card.
#7 - Any licensed features you already have will still operate just fine, including the MSO feature
#8 - The scope's model # and serial # will not change, only the reported bandwidth is updated
#9 - The mod is reverseable if care is taken to save/bag each component(highly recommended)
#10 - You will need the required BNC cables and splitters to perform a User Cal.
#11 - The parts list was compiled from pictures and component removal/measurement. I can't say the measured values are 100% exact and am not responsible if they aren't
#12 - If your scope blows up, runs away, makes you bleed(mine did) etc from the mod I'm not responsible.
#13 - All channels have a -3dB point greater then 1 GHz as they should
#14 - The noise floor closely matches a factory 3104T scope
#15 - User Cal passes with no issues
#16 - The 20 MHz BW limit works just fine after the mod
#17 - The 50 ohm path is much improved with the updated front end and use of the Teledyne 20 dB attenuator relays

Now this upgrade wasn't performed without some struggles. There were some missing parts in the earlier research so nothing worked at first. I identified those and kept going.
I modified one channel at first to see if it looked like it would work. The trigger levels and such were way off but I expected that. The bigger worry was that on some volts/div with 50 ohms enabled the values were double what they should be. That seemed like a lot for a UserCal to compensate for. Turned out to be a non-issue as the front end attenuation switches in at 200mV/div for a 1 GHz model and 500mV/div for 100-500 MHz models. So a UserCal handles the problem just fine.

The biggest issue though is that the amplitudes of each of my channels was not matched as the frequency got higher. By the time I had reached 1 GHz the channels varied by 5-10%.
I spent considerable time attempting to determine why this is. I swapped many parts and experimented but was not able to pin it down to any one component. The difference does not appear to be related to passive component tolerance. It could be Keysight has additional calibration for higher frequencies, it could be the front end ASIC varies. It could be some mystery component that was not measured/changed. Ideally the schematic of the entire front end should be drawn up which would make for much easier analysis.

In my specific case channel 1 had the highest amplitude, channels 2 and 3 matched each other and channel 4 was in between. The scope was 100% usable and when you're looking at high frequencies it is doubtful you're trying to determine the exact amplitude using a scope with an 8 bit AtoD. It still bothered me though so I had a play with LT SPICE and determined that changing the value of C1 slightly would alter the low pass frequency the nicest. To that end I changed the value of C1 to 2.4 pF on channel 4 and 3.3 pF on channel 1. This gives me amplitudes within 10-15mV between all channels when looking at a 1 Vpp signal at 1 GHz. The 3 dB cutoff frequency of all channels is between 1060 and 1070 MHz. At 1 GHz the attenuation is about 1.5 dB. Seems like pretty darn acceptable performance to me.
Another forum member will be modifying his scope in the near future, so we will see how his does.


The following forum members helped make this mod possible:
memset
HardDrive
mikeselectricstuff
TopLoser
Howardlong
adranp
HighVoltage
EEVblog(Dave)

And thanks to Keysight for making a cool scope that can do so much - please don't hate me!

Here are some pictures:

1 GHz signal @ 1Vpp in normal mode:


The same 1 GHz signal with some averaging:


The about screen after the mod:


Rise time of a 10 MHz square wave before the mod:


Rise time of the same 10 MHz square wave after the mod:


A pulse:


Input SWR of the 50 ohm path for both attenuation paths before the mod:



Input SWR of the 50 ohm path for both attenuation paths after the mod:

[TheSteve]

400 MHz ECL internal clock from an Agilent 33250A AWG measured with a 1134A 7 GHz differential active probe:


Square waves:


1 GHz signal with 3Khz 100% AM:


My updated front panel label:

[TheSteve]

Here is the parts list and matching pictures

Note all part identifiers reflect designators used in the the previous 500 MHz mod and diagrams where applicable.

The following parts are listed per channel(so you'll need 4 of each for a 4 channel scope) I have included the part # of the exact parts I used, feel free to select your own.

R1 110 ohms 1206 CRCW1206110RFKEA
R2 162 ohms 0603 CRCW0603162RFKEA
R3 100K 0805 RC0805FR-07100KL
R4 23.7 ohms 0603 CRCW060323R7FKEA
R5 23.7 ohms 0603 CRCW060323R7FKEA
R6 50 ohms 3024T only(move to position R7)
R7 50 ohms 3104T only
R8 68.1 ohms 0805 CRCW080568R1FKEA
R9 51.1K 0603 CRCW060351K1FKEA
R10 51.1K 3104T only CRCW060351K1FKEA
R11 51.1K 3024T only CRCW060351K1FKEA
R12 0 ohm (10 ohms in MSOX3024T)

C1 2pF 0603 NPO GQM1885C2A2R0CB01D ***See my comments in the first post***
C2 2pF 0603 NPO GQM1885C2A2R0CB01D
C3 4pF 0603 NPO GQM1885C2A4R0CB01D
C4 4pF 0603 NPO GQM1885C2A4R0CB01D
C5 10pF 0603 NPO GQM1885C1H100GB01D
C6 10nF 0603 GRM188R71H103KA01D
C7 10nF 0603 GRM188R71H103KA01D
C8 100nF 0603 GRM188R71H104KA93D
C9 100nF 0603 GRM188R71H104KA93D
C10 100nF 0603 GRM188R71H104KA93D
C11 100nF 0603 GRM188R71H104KA93D
C12 100nF 3024T only
C13 10nF 0402 GRM155R71H103KA88D
C14 100nF 3024T only
C15 100nF GRM188R71H104KA93D


L1 15nH green dot Coilcraft 0603CS-15NXGEU
L2 6.8nH red dot Coilcraft 0603CS-6N8XGEU
L3 6.8nH red dot Coilcraft 0603CS-6N8XGEU
L4 47nH brown dot Coilcraft 0603CS-47NXGEU
L5 6.8nH red dot Coilcraft 0603CS-6N8XGEU

Q1 IRLML2402 SOT23 (original is MMBF0201NL but that is discontinued)
D1 HSMP-3892 SOT23 HSMP-3892-TR1G
CR1 BAV99 SOT23

BD1 - ferrite bead 0805 Wurth 742792040

K1 - Teledyne A150-20-12 - 3104T only - This is the money part. I bought mine from a trusted vendor in China and verified they were 100% legit before install.
K2 - AGQ210S4H 3024T only (I recommend carefully removing using hotair)
K3 - AGQ210S4H 3104T only
***I don't recommend planning to re-use the removed AGQ210S4H relays - buy new ones***


These parts only require 1 of each for the mod:

Frequency Strapping resistors
R13 (L1) - 64.9K 0603 for 1 GHz CRCW060364K9FKEA
R14 (H1) - 100K 0603 for 1 GHz CRCW0603100KFKEA

U1507 74ACT04 SOIC(3.90mm width)

[TheSteve]

Pictures of the PCB front and back with the parts swapped/installed:



I also want to show a picture that demonstrates just how epic the HP/Agilent 1152A 2.5 GHz active probe is.
In this screen shot there is a reference image in the background showing a 1 GHz signal being fed directly into the scope. The same signal was then fed into a SMA 50 ohm termination. I am probing the termination with the 1152A active probe. You have to love how close the waveforms match even though the frequency is 1 GHz.

This is the termination being probed by the 1152A. The termination is an SMA chassis mount jack with 3 0603 150 ohm 0.1% resistors soldered on the end. Using 3 resistors seems to give the best return loss figures.


UserCal hardware:

[Muxr]

How do you sit down to use that scope with balls that big? Epic mod. 

[mrpackethead]

Really good work there.

Are you intending to publish the hack? ... I think i just need to be paitent. I see more stuff beig posted above.

[BravoV]

Subbed ! Thanks for sharing !   

[TiN]

Holy batmans that's a lot of steps. Well done, I'm almost became a time-nut reading all this  .

 

[VK5RC]

Absolutely amazing, lost for words!

[Jwalling]

Absolutely amazing, lost for words!

Same here! An incredible amount of work and perseverance pays off BIG! Nice job, Steve!

[HighVoltage]

You made it !
Just amazing how you pulled this one through.
Congratulations.

[Zucca]

Impressive!!!!

Crap now I need to buy a 3000T, anyone want a 500MHz not T?

[cgroen]

Impressive!
I have a MSOX3024T, but I'm afraid I lack the balls to do the modification 

[Dubbie]

I really am keen to try this but I am not sure I have the courage. Can you do it to a single channel? Or is is all or none?

[EEVblog]

 

[HighVoltage]

#13 - All channels have a -3dB point greater then 1 GHz as they should

You asked me before, to measure the -3dB point of my 1 GHz MSOX3104A
Here are the pictures of the measurements
I am using my trusted 3.2 GHz Agilent 8648C for a sine wave output, 50 Ohm in 50 Ohm
My MSOX3104A has the -3dB point at 1.16 GHz

[GlowingGhoul]

Incredible work. A huge boon for the hobbyist, and I doubt this will impact commercial sales one iota.

Seeing as how this has a BOM of only $200 retail, it really makes the market segmentation pricing seem absurd at this point.

Next generation entry point of the 3000 level scope should be at least 500Mhz, with a path to 2Ghz or higher.

 

[Keysight DanielBogdanoff]

Incredible work. A huge boon for the hobbyist, and I doubt this will impact commercial sales one iota.

Seeing as how this has a BOM of only $200 retail, it really makes the market segmentation pricing seem absurd at this point.

Next generation entry point of the 3000 level scope should be at least 500Mhz, with a path to 2Ghz or higher.

 

Impressive mod! It probably won't impact commercial sales like you said, but it's a great pathway to 1 GHz for guts folks.

A 1 GHz scope price has as much to do with design and NRE as BOM, and that tech trickles down into the lower bandwidth models. So, if we dropped prices on the high bandwidth models, the entire line would stop being feasible. Designing a 200 MHz scope is much, much easier than designing a 1 GHz scope. And, as is made clear by the mod, the whole backend of the scope is capable to 1 GHz (or higher  )

I wouldn't bank on a 3000 level scope starting at 500 MHz for a long, long time. I won't go into sales details, but for basically every line of scopes all the way up to the top, we sell a lot more of the lower bandwidth models than the higher bandwidth models.

[mrpackethead]

I wouldn't bank on a 3000 level scope starting at 500 MHz for a long, long time. I won't go into sales details, but for basically every line of scopes all the way up to the top, we sell a lot more of the lower bandwidth models than the higher bandwidth models.

Maybe because everyones hacking them. :-)    Probably because in all reality your average workshop/lab doe'snt need too many 1Ghz Scopes.   We have 4 100Mhz scope and 1 500Mhz Scope. The 100Mhz scopes are the workhorses and do 95% of the work..  They are cheap enough that you can leave them sitting on a bench, and not have to move them around.    the 1 500Mhz scope is on a trolley and gets moved to where its needed.    Not sure if this model scales out, but it works for us.

[philpem]

I wouldn't bank on a 3000 level scope starting at 500 MHz for a long, long time. I won't go into sales details, but for basically every line of scopes all the way up to the top, we sell a lot more of the lower bandwidth models than the higher bandwidth models.

Bandwidth: if you need it, you really need it. If you don't? Well... save a bit of brass and maybe buy SPI/UART Decode and MSO 

[electrolust]

Seeing as how this has a BOM of only $200 retail, it really makes the market segmentation pricing seem absurd at this point.

Not at all.  The BOM cost is not in the noise, but it's one of the smaller factors for a product like this (sales numbers in the thousands per year, not millions, with high NRE costs).  As something of an example, I do high grade security stuff, and folks that make EAL4 and up secure elements won't even talk to you until you're in the 100k of volume and at that volume you're a one-off.  They can't sell you unit quantities of chips even if they wanted to, because you can't afford the NRE.  When you're doing 1M+ of volume, that's when your NRE is spread across significant units and when BOM cost starts to be of primary importance.

If anything, it reflects how much of a bargain it is to buy the smaller bandwidth version of the same scope.  All the same engineering had to go into the product.  All the support costs are the same.

[electrolust]

This is amazing!!  I wouldn't do this myself, but just wow!

[lukier]

I wouldn't bank on a 3000 level scope starting at 500 MHz for a long, long time. I won't go into sales details, but for basically every line of scopes all the way up to the top, we sell a lot more of the lower bandwidth models than the higher bandwidth models.

That is at the point of sale I guess, but what about the BW upgrades? How many of these lower bandwidth ones end up getting a BW option?

[electrolust]

And, as is made clear by the mod, the whole backend of the scope is capable to 1 GHz (or higher  )

The gauntlet has been thrown!  OK next level mod is to take this thing to 1.2 or 1.5GHz!!

[electrolust]

Can you characterize the response curve?  My memory might be bad, but as I recall from the literature, the sub-1GHz models have gaussian response and the 1GHz (as shipped from Keysight) has maximally flat response.  Apologies if the posted traces show that fact, I'm a bit excited and haven't read through in detail!

[electrolust]

#17 - The 50 ohm path is much improved with the updated front end and use of the Teledyne 20 dB attenuator relays

Would this part of the mod be worth doing just on its own, for a 200MHz scope, without doing the rest of the mod?  Or at 200MHz is it not gaining you so much.

[Amazing]

Great job!  that really took guts.

scope. And, as is made clear by the mod, the whole backend of the scope is capable to 1 GHz (or higher  )

The first version of the 3000T manual mentions a 1.5GHz model that was never sold... 

[TheSteve]

I really am keen to try this but I am not sure I have the courage. Can you do it to a single channel? Or is is all or none?

This is an all or nothing mod and if you aren't sure please don't risk your scope.

SNIP
And, as is made clear by the mod, the whole backend of the scope is capable to 1 GHz (or higher  )
SNIP

Is that a challenge?
I know the front end ASIC is capable of at least 1.5 GHz as it is used in the 4000x series. My dream was a 1.5 GHz upgrade but without seeing a 4000 series 1.5 GHz front end it just isn't going to happen. It was hard enough to determine the required values for 1 GHz.
There is the jumper option on the board for 1.5 GHz but as far as I am aware it will be rejected as it isn't a 4000 series board. I have no desire to get into firmware hacking.
I don't need to sleep, I'll be pondering it.

Would this part of the mod be worth doing just on its own, for a 200MHz scope, without doing the rest of the mod?  Or at 200MHz is it not gaining you so much.

There is nothing to be gained by modifying the 200 MHz front end for a better 50 ohm match. It also wouldn't work properly as the relay/attenuator controls change when you go from 100-500 to 1 GHz hardware.

Can you characterize the response curve?  My memory might be bad, but as I recall from the literature, the sub-1GHz models have gaussian response and the 1GHz (as shipped from Keysight) has maximally flat response.  Apologies if the posted traces show that fact, I'm a bit excited and haven't read through in detail!

I do believe the 1 GHz model has the flat response. If you look at the anti alias/low pass filter on the output of the front end ASIC you'll see the 1 GHz model has an added series resistor/capacitor. In simulation this prevents attenuation above 500 MHz and changes the curve around 1 GHz.
I will plot the curve when I get a chance.

[KE5FX]

[WastelandTek]

wowwwww...

[G0HZU]

Impressive stuff...

Some equipment can be upgraded simply by creating a valid licence file. A couple of years ago I reverse engineered Agilent/Keysights option licencing system so I could upgrade my E5071 VNA to add time domain analysis. It just requires a text based licence file with a key code to unlock the option.

They appear to use a similar system on a lot of test gear, I tried upgrading a DSO 80000 series scope just by creating a valid licence file for its serial number. It took me about 10 minutes to hack the 80000 scope system and I managed to write a licence that unlocked loads of options and upgraded the BW from 4GHz to 12GHz (proved/measured with a 20GHz sig gen).


https://www.eevblog.com/forum/testgear/agilent-infiniium-dso8000a-hacking-anyone-done-this/

[G0HZU]

I'm not a scope guru and I know nothing about the 3000 series but I wonder if there is another way to do your mod without needing to change hardware?

From my limited time spent with Agilent scopes I think they sometimes have switchable front end LPF sections in them. I think Agilent prefer to limit the bandwidth in hardware if you select user settings with a low sample rate and this minimises alias issues on certain timebase settings. So maybe your scope could be upgraded in code to manage the LPF as well as doing your BW upgrade. It might not be necessary to change any components? The higher BW LPF may already be in the scope waiting to be selected? But this is just a guess.

[TheSteve]

Parts have to be changed, absolutely no question. There are three hardware versions. 100/200, 350/500 and 1000 MHz. The 100 can be software updated to 200 and the 350 can be updated to 500. Each has unique hardware filters that the laws of physics dictate.

[bson]

Isn't it likely that minor channel level variation and possibly zero variance is handled through calibration?  That looks like the ideal method if the response is otherwise reasonably flat.

[TheSteve]

Isn't it likely that minor channel level variation and possibly zero variance is handled through calibration?  That looks like the ideal method if the response is otherwise reasonably flat.

This is totally possible. But so far I have never found any information detailing any calibration info beyond the UserCal built into the scope.

[mrpackethead]

f C1 to 2.4 pF on channel 4 and 3.3 pF on channel 1. This gives me amplitudes within 10-15mV between all channels when looking at a 1 Vpp signal at 1 GHz. The 3 dB cutoff frequency of all channels is between 1060 and 1070 MHz. At 1 GHz the attenuation is about 1.5 dB. Seems like pretty darn acceptable performance to me.
Another forum member will be modifying his scope in the near future, so we will see how his does.

Do you think this will be the same on all scopes, or is this something that more likely will need to be tweaked on a per scope basis?

[TheSteve]

A rough guess suggests it will vary on all scopes. We should know in a week or two when another scope meets the soldering iron.

[LabSpokane]

And, as is made clear by the mod, the whole backend of the scope is capable to 1 GHz (or higher  )

The gauntlet has been thrown!  OK next level mod is to take this thing to 1.2 or 1.5GHz!!

The next step is for someone to design and open-source active probe to make use of this kind of horsepower between 500Mhz and 1GHz.  Keysight's 2795A probe starts at $1K ea, which is a lot less than what they used to be, but still not inexpensive. 

[Someone]

And, as is made clear by the mod, the whole backend of the scope is capable to 1 GHz (or higher  )

The gauntlet has been thrown!  OK next level mod is to take this thing to 1.2 or 1.5GHz!!

The next step is for someone to design and open-source active probe to make use of this kind of horsepower between 500Mhz and 1GHz.  Keysight's 2795A probe starts at $1K ea, which is a lot less than what they used to be, but still not inexpensive.

Keep an eye out for any of the N2795A, 1156A, and 1152A. All come up well under $1000.

[TheSteve]

And, as is made clear by the mod, the whole backend of the scope is capable to 1 GHz (or higher  )

The gauntlet has been thrown!  OK next level mod is to take this thing to 1.2 or 1.5GHz!!

The next step is for someone to design and open-source active probe to make use of this kind of horsepower between 500Mhz and 1GHz.  Keysight's 2795A probe starts at $1K ea, which is a lot less than what they used to be, but still not inexpensive.

Keep an eye out for any of the N2795A, 1156A, and 1152A. All come up well under $1000.

Keep in mind that to use the 1152A with the 3000A/3000T series of scopes the probe needs to be modified.
https://www.eevblog.com/forum/testgear/agilent-1152a-active-probe-'smartprobe'-conversion-for-dsox3000-series-scopes/

[mrpackethead]

is this hack likely to work on a DSOX3014T ? 

[TheSteve]

is this hack likely to work on a DSOX3014T ?

Yes, the DSOX3014T has the identical hardware as the MSOX3024T I started with.

[TheSteve]

This is why I suggest nobody tries to re-use the original relays. I used as little hot air as possible to remove them yet they just don't look so great. All I really cared about was nothing else being exposed to excessive heat so the hot air was focused directly on the relays to remove them.

[Dubbie]

Are they not through hole?
Why did you not just suck the solder from the pins?

Worried about damaging the pads?

[TheSteve]

Nope, not through-hole. They are tiny little SMT buggers.

[mrpackethead]

Did you preheat the board?

[mrpackethead]

K1 - Teledyne A150-20-12 - 3104T only - This is the money part. I bought mine from a trusted vendor in China and verified they were 100% legit before install.
K2 - AGQ210S4H 3024T only (I recommend carefully removing using hotair)
K3 - AGQ210S4H 3104T only
***I don't recommend planning to re-use the removed AGQ210S4H relays - buy new ones***

Just a little confused by this..       



and can you share ( pm maybe ) the trusted source for the part.
Which bits are replaced if I'm going from a 3014T?   

[adranp]

:mrpackethead

K1 has to installed (the most expensive part from the upgrade BOM and the most hard to get)
K2 has to be removed
K3 has to be installed (new part required due to hotair removal procedure which will most probably damage the part from K2)


Steve did not preheat the board as far as I know..

[mrpackethead]

My scope is 20,000km away, so i dont' have one to look at.  :-)

K1 has to installed (the most expensive part from the upgrade BOM and the most hard to get) -    So this part is unpopulated?

K2 has to be removed -
K3 has to be installed (new part required due to hotair removal procedure which will most probably damage the part from K2)


In the photos it seems that both K2 and K3 are left installed??

Steve did not preheat the board as far as I know..

[tautech]

See #17 in the OP.

[adranp]

:mrpackethead

K1 is unpopulated in models lower than 1Ghz.

Look carefully in the picture for K2 and K3 designators. K3 is unpopulated in lower than 1Ghz models and K2 is populated. There's the same relay at K502 position which is going to stay there (in all models).



Also wanted to add that probably I'll be the next person doing this mod (some of my parts are here already and some will arrive next week)..

Steve did a wonderful job putting this mod in a form that's quite easy to understand.. He explained  a lot of things he encountered..

As he said already, please be advised this mod is not very simple. The number of parts to be added/swapped/removed is quite a task. Without proper soldering skills and tools this is going to be a nightmare.
Before doing this mod I highly advise any of you to look at the other forum thread and understand the mod for 350/500Mhz and then come here and look at what should be done for 1Ghz.
There are a lot of steps which could damage the PCB, so be advised on that.

[mrpackethead]

Got it! there are still 2 of the Relays on the board.   K2 is removed and K3 installed.   theres a relay that doesnt get moved at all..   I did'nt see K2 is in the text on the unpopulated pads.

I suspect that some preheating will make it easier to get the thing off..  ALso reduces the risk of damaging the board. Hate to lift a track.. You might also be able to use some low melt solder in there...

[mrpackethead]

Steve did a wonderful job putting this mod in a form that's quite easy to understand.. He explained  a lot of things he encountered..

In deed he has.  I'd just failed to read the pictures properly.

As he said already, please be advised this mod is not very simple. The number of parts to be added/swapped/removed is quite a task. Without proper soldering skills and tools this is going to be a nightmare.

I'm pretty confident that i can do this, and i have a well equipped lab with good rework tools and inspection.   Its a case of being careful and through, and making sure that you can absolutely understand all teh steps *BEFORE* you start.          I'm away for another week, but i'm going to start ordering the parts, so i can get onto doing mine when i get back.   

There are a lot of steps which could damage the PCB, so be advised on that.

Yes..   I need to have a look at the PCB and see if i can get it in the big preheater.  Its just so much safter to get the pcb up to about 150C, and then start with the hot-air..   

[adranp]

Hotair is required just for the relay removal at K2. 
On the back of the board you have the BNC connectors which might give you some trouble putting the board on preheater.

A tool which would make your life much easier would be a soldering tweezer.

[TheSteve]

Did you preheat the board?

As adranp mentioned I did not preheat the board at all. If I was doing it again I might gently warm the entire board with a heatgun. I had planned to sacrifice the relays all along though. The space is very tight so you can't direct the hotair right at the legs of the relays, it basically gets directed right on the top of them. The relay you need to keep and not damage is only a few millimeters away(less then a quarter inch).
Lifting traces shouldn't be an issue unless you're way to aggressive trying to remove the relays. The PCB is of high quality and you should be very gentle when removing the relays.

[nctnico]

You could use polyimide tape to shield parts of the board from the heatgun. Recently I did rework on a delicate board as well and the polyimid tape worked like a charm.

[TheSteve]

You could use polyimide tape to shield parts of the board from the heatgun. Recently I did rework on a delicate board as well and the polyimid tape worked like a charm.

This was absolutely done - and metal shields too. Without it the other relays would be cooked too.

[mrpackethead]

Makes me think that i should buy some extra relays, just in case.

[Gandalf_Sr]

Damn Steve - DAMN! 

[TheSteve]

Hmm, anyone have a DSOX4154 and want to take some pictures? 

[mrpackethead]

1Ghz is plenty for me. but i can see the challenge.   how much attenutation are you seeing there..  i saw 120mV PP, but not sure how what you were inputing.

[TheSteve]

I was inputting 1 Vpp at 1.5 and 2 GHz. The attenuation is completely expected of course as the input filter maxes out at 1 GHz and the antialias/low pass filter is also tuned to 1 GHz. Both would need to be altered to have a true 1.5 GHz of bandwidth. I was impressed with the triggering though, even at 2 GHz it was solid.

[mrpackethead]

Im having trouble getting the atenuators.. ANy suggestions of where to get them.

[mrpackethead]

Sorry for the bump, but i'm really struggling to be able to locate those attentuators? Any one can you make a suggestion.. Maybe i'm looking in the wrong place.

[TheSteve]

A few weeks back avnet had stock and you could buy them in single quantities, now it appears they have none and you need to buy 25 of them. I haven't looked at official distributors outside of US/Canada myself. You can also get quotes via seekic. I got mine from here: xingsheng.member.seekic.com

[KE5FX]

Sounds like Keysight has been buying up all the attenuators. 

[Jwalling]

Sorry for the bump, but i'm really struggling to be able to locate those attentuators? Any one can you make a suggestion.. Maybe i'm looking in the wrong place.

http://www.oemstrade.com/search/A150-20-12

Online components (if these are legit...)

[adranp]

I can confirm my relays are also from xingsheng.. They just arrived 2 days ago.. Seem legit and also new.. Take great care on seekic as there are a lot of sellers who sell used parts..

[adranp]

Just a quick update. I have successfully upgraded my scope to 1GHz.

One important thing to add is that there is 100% chance to remove safely and reuse the K2 relays using preheating plate and hot air + kapton tape and metal shields. I've preheated the pcb at around 90 degrees Celsius (measured near the relay) and then removal was without any issues.
No discolouration or melting on the removed relays.

I'll post detailed info in a few days.

[Zucca]

I'll post detailed info in a few days.

Please!!!!!

[adranp]

Please bear with me a little more.. The mod is working perfectly but we're trying to give you a nice bonus raising the bar to 1.5 Ghz

[Zucca]

ok, now I can't sleep anymore. Thank you.

[TheSteve]

Hah - I dream of more bandwidth every night! Anyway, we're working on it and the dream is 1.5 GHz.

[Netroman]

@TheSteve: Thanks 1000 times for the superiour description and hard work to make this mod possible - also thanks to all the supporters of Steve.

I have completed the mod on my MSOX3024T - now with 1 GHz. I used a special rework station to be able to solder the 0603 and 0402 parts (JBC Nase) - no chance with my old Ersa, even with the smallest tips.
There was a lot of soldering, but at the end successfull

The only problem I have now, is, that the user calibration (I use 4 equal length cables from Telegärtner) fails after about 1/2 min.
Though measured Signals look equal on all 4 channels - just slightly difference in measured voltages, which does not matter much for me (but maybe for cal?).
Maybe it's possible to figure out, which channel causes the problem - for now, I have no clue. I wonder, if the Serialport gives some hints, where the calibration fails.

Nevertheless I'm very happy with my 'brandnew' 1 GHz scope 

[TheSteve]

Netroman - I'd say there is an issue with an attenuator stage or the drive signals for an attenuator stage based the PM's you've sent and the data you provided.

[Netroman]

I've just completed my mod (MSOX3024T now 1GHz) and it works great - many thanks to all envolved users from this Forum; especially Steve for additional hints and support.

If someone needs contacts, i got plenty of offers for the teledyne relays. Most where between ~40-59 US (i bought mine much too expensive and they are not very hard to get  ).

For the really tiny parts i used a JBC NASE nano rework station - not cheap, but definitive worth the money. I did not believe that, but i'll never buy another brand anymore.

I had some problems with the user calibration, but the reasons were just wrong ordered parts. Especially the Driver "74ACT04" - MUST be an "ACT", because it is driven by Levels about 2.4 Volts and Needs to be able to work with TTL-Levels. So the "ACT" is absolute must (i had a "HCT" which has much too low power, whilst the ACT delivers up to 25 mA).

And i made absolute equal length cables for the calibration with 250mm (important: not longer than 300mm per cable), also bought hight quality tee-connectors bnc.

Though i was successful in reusing the desoldered cheaper relays, i would also suggest to buy new ones, because these should work for years without Troubles. I replaced the two ones in channel 1 whilst finding out my calibration problems.

Best regards from Austria, Josef

[EE-digger]

Thanks for your report !  Now I'm stoked again to perform the mod.  I had a thought on clean shield removal.  What do you guys think about heating a single corner, sliding a piece of Kapton film under it, then on to the next 'til done?  Re-soldering should be a piece of cake but I might use NC paste to keep it neat.

Also, 74ACT is almost twice as fast as 74HCT.  Is this the cal signal?  The 74HCT rise time may have been inadequate.

[TheSteve]

Thanks for your report !  Now I'm stoked again to perform the mod.  I had a thought on clean shield removal.  What do you guys think about heating a single corner, sliding a piece of Kapton film under it, then on to the next 'til done?  Re-soldering should be a piece of cake but I might use NC paste to keep it neat.

Also, 74ACT is almost twice as fast as 74HCT.  Is this the cal signal?  The 74HCT rise time may have been inadequate.

Removing the shields isn't actually too bad. You can just lift them up corner by corner. The 74ACT04 drives the FET's that turn the Teledyne attenuator relays on and off.

[EE-digger]

There must be some other loading on the '04 output then, that does not permit the HC04 to satisfy the Vgs.

[Netroman]

@EE-digger: I broke a small piece of GND-route, because the shields do not really bend well. I suggest to spend some solder wick to remove as much as possible before you lift the corners. IMHO the corners do not lift (bend) more then 1/2 to 1 mm - that was not enough (too much solder on it and at first i did not use wick) in one case, so i ripped the route :-(

Josef

[adranp]

As I said previously, lifting the shields works best with pre-heater and hot-air gun. This way you won't have problems. Solder wick requires good skills.

[EE-digger]

adranp: That's why I thought that a hot iron, slide some high temp, thin film under that corner.  Clean up after all four have been lifted.  I may give it a shot.  I have bottom heat but would rather not involve that side.  I know it would work great though 

Did you ever finish your mods?

Josef:  Sorry about your lifted copper.  That can be heartbreaking but glad that your scope works well 

[Samogon]

Got 4024A and being inspired by TheSteve will try to mod it to 1G or 1.5G with his and hopefully community help.

here are some pictures of areas we interested.

[Samogon]

In ideal if someone can open little expensive 4104A or 4154A scope remove backside shield and make hirez pictures that would be fantastic.

[Pinkus]

The "back" picture shows a lot of flux as if somebody already reworked this. Did they (Agilent) really deliver such a board?

The front end looks (almost) identical to the 3000 series, thus it should be not a big deal. Though the mod for 1.5 Ghz has afaik not been made yet.

[sibeen]

You are all mad, and my DSOX3024T is sitting on my bench and madly agreeing with me.

As I work in the power area I sometimes go as high as the 60th harmonic, so 3 kHz. I think I'll leave mine well alone, but respect to those who did this mod.

[Samogon]

in contrast to 3000T series we have already populated inverter U1507 74ACT04  on 3000T corresponds to U1613 on 4000x
This is how CPU manages front attenuator relays. It uses serial data going to Serial to parallel converter U502 74AHCT594 and then finally transistors drive relays.

[Samogon]

The "back" picture shows a lot of flux as if somebody already reworked this. Did they (Agilent) really deliver such a board?

The front end looks (almost) identical to the 3000 series, thus it should be not a big deal. Though the mod for 1.5 Ghz has afaik not been made yet.

Well board has flux all over it especially where through hole components are, looks to me nobody cared to clean it. But board looks intact

[Samogon]

You are all mad, and my DSOX3024T is sitting on my bench and madly agreeing with me.

As I work in the power area I sometimes go as high as the 60th harmonic, so 3 kHz. I think I'll leave mine well alone, but respect to those who did this mod.

Well it depends what tasks you are aiming. For you probably 50Mhz scope would be enough.
For me just as example i needed 500MHz scope minimum to measure Pulse Edge Time of Agilent 33250A when calibrating it.

[TheSteve]

Had another look at the input SWR to my modded scope tonight with a newer VNA. I am quite pleased with what I see. Generally scopes seem to be specified as having an input SWR of 1.5:1 or less over the rated bandwidth with the 50 ohm input enabled. The scope beats this spec with and without the Teledyne attenuator switched in to 1.5 GHz. With that in mind I'll have another look at the low pass filter components and see if we can't finally mod the 3000t series to a full 1.5 GHz.

100 mV range(Teledyne switched in):


200 mV range:

[Samogon]

Monster TheSteve!

[2N3055]

I apologize if somebody already asked this. I was reading 3000T X-series User manual and found this mentioned in few places:
"With the 3000T X-Series 1 GHz and 1.5 GHz bandwidth models"
Is that just remnant from when they rewrote (reused,recycled) manual from 4000 series or there ever was mention of 1.5 GHz version of 3000T ?
Regards,
Sinisa

[TheSteve]

I apologize if somebody already asked this. I was reading 3000T X-series User manual and found this mentioned in few places:
"With the 3000T X-Series 1 GHz and 1.5 GHz bandwidth models"
Is that just remnant from when they rewrote (reused,recycled) manual from 4000 series or there ever was mention of 1.5 GHz version of 3000T ?
Regards,
Sinisa

There is no factory released 1.5 GHz 3000 series model.

[badbiki]

Ok I'm keen. Ordered all parts bar the relays.

I've PMd someone on here about them.. if anyone has four cheap?

I have a MSOX3024T and assume I need them, even tho the comment;

K1   A150-20-12    - 3104T only - This is the money part. I bought mine from a trusted vendor in China and verified they were 100% legit before install.

says only for 3104T.. bit weird.

Description	Manufacturer	Manufacturer Part Number	Digi-Key Part Number	Designator	Reference Designator	Qty	Unit Price
FERRITE  BEAD 600 OHM 0805 1LN	Wurth Electronics Inc.	742792040	732-1620-1-ND	BD1	Per Channel	1	$0.25
CAP CER  2PF 100V C0G/NP0 0603	Murata Electronics North America	GQM1885C2A2R0CB01D	490-3555-1-ND	C1 C2	Per Channel	2	$0.59
CAP CER  4PF 100V C0G/NP0 0603	Murata Electronics North America	GQM1885C2A4R0CB01D	490-3557-1-ND	C3 C4	Per Channel	2	$0.59
CAP CER  10PF 50V C0G/NP0 0603	Murata Electronics North America	GQM1885C1H100GB01D	490-6087-1-ND	C5	Per Channel	1	$0.76
CAP CER  10000PF 50V X7R 0603	Murata Electronics North America	GCM188R71H103KA37D	490-4778-1-ND	C6 C7	Per Channel	2	$0.10
CAP CER  0.1UF 50V X7R 0603	Murata Electronics North America	GCM188R71H104KA57J	490-8020-1-ND	C8 C9 C10 C11 C12 C14 C15	Per Channel	7	$0.17
CAP CER  10000PF 50V X7R 0402	Murata Electronics North America	GCM155R71H103KA55J	490-13295-1-ND	C13	Per Channel	1	$0.10
HIGH  RELIABILITY AND SMALL MOLD	Rohm Semiconductor	BAV99HMFHT116	BAV99HMFHT116CT-ND	CR1	Per Channel	1	$0.25
DIODE  PIN 100V 250MW SOT-23	Skyworks Solutions Inc.	SMP1321-005LF	863-1097-1-ND	D1	Per Channel	1	$0.78
RELAY  TELECOM DPDT 2A 125V	Panasonic Electric Works	AGQ210S4HZ	255-2096-1-ND	K2	Per Channel	1	$2.17
MOSFET  N-CH 20V 300MA SOT-23	ON Semiconductor	MMBF0201NLT1G	MMBF0201NLT1GOSCT-ND	Q1	Per Channel	1	$0.57
RES SMD  110 OHM 1% 1/4W 1206	Vishay Dale	CRCW1206110RFKEA	541-110FCT-ND	R1	Per Channel	1	$0.10
RES SMD  162 OHM 1% 1/10W 0603	Panasonic Electronic Components	ERJ-3EKF1620V	P162HCT-ND	R2	Per Channel	1	$0.10
RES SMD  100K OHM 1% 1/8W 0805	Panasonic Electronic Components	ERJ-6ENF1003V	P100KCCT-ND	R3	Per Channel	1	$0.10
RES SMD  23.7 OHM 1% 1/10W 0603	Vishay Dale	CRCW060323R7FKEA	541-23.7HCT-ND	R4 R5	Per Channel	2	$0.10
RES SMD  68.1 OHM 1% 1/8W 0805	Vishay Dale	CRCW080568R1FKEA	541-68.1CCT-ND	R8	Per Channel	1	$0.10
RES SMD  51.1K OHM 1% 1/10W 0603	Vishay Dale	CRCW060351K1FKEA	541-51.1KHCT-ND	R9 R10 R11	Per Channel	3	$0.10
RES SMD  10 OHM 1% 1/10W 0603	Yageo	AC0603FR-0710RL	311-10LDCT-ND	R12	Per Channel	1	$0.10
RES SMD  64.9K OHM 1% 1/10W 0603	Panasonic Electronic Components	ERJ-3EKF6492V	P64.9KHCT-ND	R13-L1	Per Device	1	$0.10
RES SMD 100K OHM 0.5% 1/10W 0603	Vishay Dale	CRCW0603100KDHEAP	541-100KAYCT-ND	R14-H1	Per Device	1	$0.32
IC INVERTER 6CH 6-INP 14SOIC	Texas Instruments	SN74ACT04DR	296-1065-1-ND	U1507	Per Device	1	$0.48

This is my BOM. I've used GCM over GRM cap parts due to availability and better specs being automotive. I could be wrong tho.

[TheSteve]

You absolutely need the Teledyne attenuator relays to perform the bandwidth upgrade(they are used in the 3104T only which is why you need them as that is what hardware you're upgrading to).

[badbiki]

Ye I reread the upgrade and the comment about the upgraded relays makes it clear. I have four on order so I’ll see how it goes.

Is anagilent 1130A probe sufficient for testing and general scoping? Can eBay one for around 1k

Ill take some photos of my unit pre and post. Will use my ESD room and straps on all irons for sure!

[badbiki]

My relays arrived from https://www masterelectronics com/teledyne-relays/a1502012-12686042.html

Their documentation seems legit and they came well packaged. Gold pins and underbelly with a nickel played top and markings.

Getting the shields off was a pain. Ended up wiking most of the solder off each corner and then using a heat gun and flux to lift a side at a time. I would t recommend prying corners. The sheils have tabs mid way forcing a vertical lift. They really could have used 1/5 the solder to put these on IMHO.

A lot of residue marks on the board before dissassemby and I even found a stray solder ball!

Perhaps I should X-ray the board before final assembly:)

It really is a work of art inside. My pre mod user cal ran through to success so here goes.

I’m removing, desoldering, cleaning (Kim wipes and IPA) then fluxing and reapplying or installing new parts. Am I missing anything?

I’ll photo check with my SLR pre/post mods.

ESd Mat and strap in use.

Using lead free solder. I’m assuming this is RHOS mostly?

[TheSteve]

The shields can be a pain, with experience they get much easier. Add a little leaded solder to each joint, then use good quality wick to remove the solder. I am generally able to then lift each corner .5mm or so one at a time working my way around. If they don't want to move then just add heat while lifting, they should stay raised when you remove the heat as there should be next to no solder left holding them in place.

The scope is certainly assembled with lead free solder. I always use leaded during rework.

More then anything I'd say just take your time with the mod, don't rush it. To me the biggest challenge was removing the existing relays as I didn't want to damage anything else. With some board preheating(which I didn't do) they will come off very nicely though. The pads are very tiny on the signal path so inspect your connections very carefully. It is too much of a pain to be disassembling and reassembling too many times.

[badbiki]

I agree with taking time and not rushing. Lifting tracks is my worst fear.

Touch wood, I’ve only lifted 1980s era traces thus far.

I too added a little leaded to help it flow, with tacky flux and good quality wick. CHIPQUIK 291 flux and chemtronics no clean desoldering braid, multiple sizes with hoof tip

I was trying not to mix types of solder during rework. I find it comes out dull and doesn’t wet well otherwise. Even thought I hate reworking lead free.

I was thinking of using kapton tape and some little insulators I have from my 3D printer to act as air barriers to remove the relays. I don’t have an IR or heated mat under my pcb holder at home. Perhaps I should borrow one for the weekend.

Also don’t yet have my active GHz probe (shipping atm) or a ghz source handy.

Any ideas of some cheap quick solutions for testing? My friend works at a lab with Calibrated rf gear, or I may call in a favour to use some equipment at my EDM.

Do you tack the shields down with a little less solder?

Also, one channel had a green sticker on it. I noticed some pictures have different colours or none at all. Are they a post check or marker for component values? As in they have a different set to pass?

Green dot, red dot, orange... what do they mean?

[TheSteve]

No idea on the dots, but it is normal. Ideally to determine performance you need a signal generator that goes to 1.5 GHz or so with a level output. You don't want to use a probe for testing, the signal generator should be directly connected to a channel input with 50 ohm mode enabled.

I would use kapton tape to protect the areas around the relays, or metal shields if you have them. You can always at least warm the board a little with a heat gun - just don't go crazy.

[badbiki]

Lifted one pad on a removed relay... could patch if going backwards but otherwise alll relaysbin.

Kapton tape and insulation pads from  3D printer hot ends works well. Make wrap around a for the protecteded relays and a lifted one for the removal. Easy.

Not good enough to reuse but don’t damage the remaining relay

More tomorrow.

[badbiki]

MOd complete spent hours cleaning residue from all the traces and components.... so many hours!

I matched the 27.5 ohm resistors in pairs between 3 and 9mOhm difference. I would think it would be wise to also match the mirrored capacitors also, and match the mirrored inductors per channel.

Ideally I would have also bought more of C1 and C2 to match filter frequencies between channels. However it was late and I didn’t have a good 4wire measurement system setup for 0603/0805 passives. I’ll revise my BOM above and purhaps post my annotated drawings which print well on B&W and show movements/removals.

I’ll take it to my friends RF lab soon to check each channel at high frequencies. So far the user calibration passes so long as my cables T out to 1,3 and 2,4 otherwise it failed the first time.

Top hacking

[Samogon]

To measure 1pF caps is a big deal, not many systems could do it.

[badbiki]

I had a very quick hookup using a Rigol 70kHz-3.2GHz spectrum analyser set on 0dBm with each channel terminating into 50ohm with a 400mm BNC to SMA cable. Too quickly as I was rushing out the door to get home.

I will setup better for it next time to do a sweep up the frequency range and perform a segmented capture across the MHz and into the GHz.

Ch/Freq	1GHz (mVpp)	1.5GHz (mVpp)	1GHz (dBm)	1.5GHz (dBm)
Ch1	562.21	145.34	-1.02	-12.77
Ch2	491.96	125.38	-2.18	-14.06
Ch3	481.91	128.14	-2.36	-13.87
Ch4	511.31	20.653	-1.85	-29.72

I have a feeling that the last entry I captured was not setup correctly

I should have had this set as 3.97940 dBm for a clean 1Vpp signal.

I read a 1.699-1.718ns rise time on the trigger output with ~200MHz bandwidth measurement with Math FFT(d/d(t)).

[maxwell3e10]

Not exactly on topic, but I've been collecting shorted input noise spectra for various oscilloscope in this thread:https://www.eevblog.com/forum/testgear/oscilloscope-input-noise-comparison/

So far R&S RTM3000 is the winner, so to be fair we need some data from a Keysight 3000 series scope. It would also be interesting to compare the noise for mod and non-mod versions.

[badbiki]

Ye sure why not. That’s a lot of data to collect every div every channel

[1359944032]

I am going to buy 3014t and upgrade it to 1Ghz, but I don't know how to crack the license. Can someone tell me, thank you very much.
I am currently learning English

[badbiki]

Moving the jumpers “unlocks” the higher frequencies.. no license work to be done. Unless there are future software updates that block it?

Have fun flux, clean, leave no traces of muck!

[1359944032]

Thanks for your reply, the license I am referring to is to open more features. For example, MSO, FRC, etc.

[TheSteve]

Thanks for your reply, the license I am referring to is to open more features. For example, MSO, FRC, etc.

That information is all contained in the original hacking thread here:
https://www.eevblog.com/forum/testgear/dsox2000-and-3000-series-licence-have-anyone-tried-to-hack-that-scope/

[1359944032]

Thank you very much, forgive me for not looking at it seriously .

[oaba]

To save the pads.
Use low temperature solder (Like chipquick, etc. ) first with load of flux. Prior removal.

[EE-digger]

Fearing the shields, I held off any mods for a long time.  Finally did a 500MHz this morning on my 3000T and couldn't be happier.  605MHz BW (0.707) and 750MHz (50%).  Triggers beautifully everywhere but response hits a brick wall just a hair above 1GHz on this mod.

But regarding shield removal, it was a piece of cake.  I used a Pace medium/large chisel and Chemtronics Soder-Wick of the Rosin type.  Solder wicked away easily and the pads cleaned up like new.

Did the component removal with hot air and, against my better judgement, with no bottom heat.  This does take a bit longer when an attached via ties to a plane but still not bad.  This was with a Quick 861DW hot air station, my new favorite.  Super low air velocity is a plus for this tool.  It made my old Pace ThermoJet look like a toy in comparison to the wattage it delivers to the air.

With irons, the biggest shortcoming in SMT removal is inadequate heat and too small a tip, which cannot transfer the heat adequately.  Especially with the higher melting point of unleaded solder.

TheSteve had a good idea with his "undo" kit of parts.  He used separate bags.  Being somewhat lazy, I used double sided tape stuck to a card.  Parts are laid on the tape by channel and rough arrangement.  I let the parts cool first so they wouldn't get permanently "glued" to the card.

[maomi84]

This is amazing！THANKS!  Steve
I `ll do it myself.
I have more question.
1、About K1 relay,Can I use 10dB relay here , such as  a150-10-12 & a150-10-5(Add  dc-dc ),I can only buy 10dB relays.
2、Is calibration necessary after mod.

[TheSteve]

I doubt you can sub in a different value for the attenuator relays and have the scope handle range changes properly.
The self calibration seems to take care of the calibration issues. If this is adequate for your use case only you can decide.

[dew]

There seems to be more differences in in 4000 series hardware. I took some pictures of the area with missing Cyclone IV FPGA and it's surrounding on both sides of the board. Firmware would be puzzled when it fails to find that FPGA that suppose to be there on 1 GHz model. Lots of bypass capacitors and other stuff are missing there as well on 200 MHz model.

[analogRF]

There seems to be more differences in in 4000 series hardware. I took some pictures of the area with missing Cyclone IV FPGA and it's surrounding on both sides of the board. Firmware would be puzzled when it fails to find that FPGA that suppose to be there on 1 GHz model. Lots of bypass capacitors and other stuff are missing there as well on 200 MHz model.

I dont have this scope but I think that FPGA is for one of the options (USB decoding maybe?) so if you dont enable that option, I guess it should work 

[TheSteve]

The 4000 series has the extra FPGA installed on the 1 and 1.5 GHz units.

[EE-digger]

** parts have been sold **

I decided to sell the parts I had collected for a mod of my 3014T.  All are new, from distributors, except for one of the semi's may have been from ebay.

[maxwell3e10]

This is amazing level of hacking! I am wondering if it would be slightly simpler if one starts with a 500MHz 3054T? Would that substantially reduce the number of components that need to be replaced to get to 1 GHz?

[EE-digger]

TheSteve will probably chime in with better info but I don't think there is an easy method of identifying the parts that need to be swapped.  I believe other efforts started with the 100MHz model.

Also, keep in mind that 500MHz units I've looked at actually had a bandwidth around 600 to 625 MHz.  I believe I've seen that the 1GHz scope has more of a brick wall above 1GHz (whereas the lower BW scopes keep going and going, albeit with loss of amplitude.)  Just an FYI.

[EEVblog]

This is amazing level of hacking!

Agreed. I'm impressed that people are willing to hardware mod such an expensive high end scope.

[2N3055]

This is amazing level of hacking! I am wondering if it would be slightly simpler if one starts with a 500MHz 3054T? Would that substantially reduce the number of components that need to be replaced to get to 1 GHz?

Did you read this topic?
Literally in first post by OP there is a link to 500 MHz conversion by Memset where it is explained.
https://www.eevblog.com/forum/testgear/keysight-3000t-scope-1-ghz-hardware-upgrade-mod/msg1245159/#msg1245159
500 MHz conversion is substantially easier.

Sorry my memory serves me badly... That particular conversion was 3000A, not 3000T to 500MHz.

[TheSteve]

The 500 MHz mod for the T series should be roughly the same as the A series however I don't think anyone has ever actually done it to verify 100% the exact components that need to be changed. And yes, it would be much simpler compared to the 1 GHz mod.

[tv84]

Agreed. I'm impressed that people are willing to hardware mod such an expensive high end scope.

After Steve lead the way, for others should be child's play (except me, of course... ).

[Keysight DanielBogdanoff]

The 500 MHz mod for the T series should be roughly the same as the A series however I don't think anyone has ever actually done it to verify 100% the exact components that need to be changed.

I haven't seen it done either and agree that it would be roughly the same. There's not a lot of difference in signal paths between the A/T/G versions.

[TheSteve]

The 500 MHz mod for the T series should be roughly the same as the A series however I don't think anyone has ever actually done it to verify 100% the exact components that need to be changed.

I haven't seen it done either and agree that it would be roughly the same. There's not a lot of difference in signal paths between the A/T/G versions.

The 1.5 GHz mod is more fun, wouldn't you agree? 

[pquadrat]

Agreed. I'm impressed that people are willing to hardware mod such an expensive high end scope.

After Steve lead the way, for others should be child's play (except me, of course... ).

I did the 500MHz mod on a 3104T. Working perfectly. Before calibration, the bandwith was about 750Mhz, which gets "corrected" in calibration.

I did not even know that it was for the A model. Everything seems to be identical.

[maxwell3e10]

The 500 MHz mod for the T series should be roughly the same as the A series however I don't think anyone has ever actually done it to verify 100% the exact components that need to be changed.

I haven't seen it done either and agree that it would be roughly the same. There's not a lot of difference in signal paths between the A/T/G versions.

The 1.5 GHz mod is more fun, wouldn't you agree? 

To summarize the basic difference if  I understand it correctly: upgrading up to 500 MHz requires changing a few L, C and R per channel. The most difficult part is unsoldering the RF shields. To upgrade to 1 GHz requires changing relays and other multi-terminal components which are trickier to desolder.

[TheSteve]

Pretty much, the 1 GHz mod is a much more extensive upgrade - and it costs a lot more because of the Teledyne attenuator relays.

[maxwell3e10]

Pretty much, the 1 GHz mod is a much more extensive upgrade - and it costs a lot more because of the Teledyne attenuator relays.

It's good to know the price difference between 500M and 1GHz versions is not just pure mark-up 

[EE-digger]

Pretty much, the 1 GHz mod is a much more extensive upgrade - and it costs a lot more because of the Teledyne attenuator relays.

It's good to know the price difference between 500M and 1GHz versions is not just pure mark-up 

Not pure ... let's just leave it at that.  The R&D for a company the size of Keysight to develop a 1GHz scope is probably significant.  It was done a long time ago though, just like the Megazoom IV.

I had all parts on hand for the 1GHz mod and decided to try the 500MHz first, which was simple.  I've gotten used to 0402 and 0201 parts though so the component swaps were for BIG components.  I thought I had marked photos of the 3000T to follow.  Matter of fact, it was the 3000T because it was a 3014T but had footprints for the Teledyne relays.  3000A did not.

There are around 132 or so components for the 1GHz mod.  I would have done it but finally, a pristine 3104T appeared and with option bundle to boot.  Someone on here grabbed the parts just to get the 4 relays in the set.