FS [USA] : Broken Tektronix DPO7104 (ADC failure) for parts or repair

[TiN]

Hi-end scope repair project looking for a new home, as I'm going to optimize my project list and this need some careful repairs. Perhaps somebody need parts for another DPO7104/7254/7354 fix.

Up for sale is 11 year old Tektronix DPO7104 (non-C version) with 2SR option (doubled to 40 GS/s sample rate). It is NOT WORKING, due to ADC chip failure (custom ASIC which is shorted to ground). Same Tektronix ASIC ADC likely used on another Tek DPO scopes, such as MSO/DPO4000/5000 series, but I'm not sure.



There are no mechanical damages, buttons, connectors, chassis are all in good condition.



Internally nice and clean. Heatsink retention clip for northbridge chipset on PC board is separated, as it was loose when scope was delivered. It is bundled together in bag.



Touchscreen display, x86 PC, power supply and interface board all working good. Scope boots native Tektronix Windows XP, loads Tektronix Scope applications with power on diagnostics error.



Here's acquisition board and damaged ASIC location. Bottom side has burnt traces and removed power bypass components at affected ASIC. No attempt of any BGA rework was done, board still AS IS, as I have no donor chips or parts to proceed on this.

Diagnostics error:

* Processor - PASS, 0 failures
* Registers - Error 223, 3 failures
* Acquisition - Error 311, 5 failures
* Trigger - Error 411, 6 failures

Since scope use all ADCs at all times in interleaving, none of the channels can perform the waveform capture.



Selling for what I got it for, $2700 USD.
Scope located in USA, payment over PayPal.

Sold AS IS, no returns. No accessory or probes included, only the scope.

[bloguetronica]

Hi,

Let me ask you a question. Did you bought it already broken? Or you're just selling a broken (and possibly useless) scope for the price you got it new?

I'm also wondering how repairable is this.

Kind regards, Samuel Lourenço

[TiN]

I've bought this scope as parts condition for listed above price.

If you know where to buy DPO7K scope (be it new, or used) for less than 7K$, let me know, I'd like one MSRP for this unit even without 2SR option is >20K$.

If you have donor ASIC chip/board, experience in repair probably this is very repairable, as other parts of the box are working good.
But you already know this by now. 

[nctnico]

Without a working acquisition board it is just an outdated PC in a box with excess knobs. Repairing the acquisition board will be very difficult for various reasons.  I think it will be better to get a donor acquisition board from somewhere but that might give problems with mismatching serial numbers. I'd keep it and hunt for a replacement acquisition board.
BTW: did you remove the capacitors or did you receive it this way?

[TiN]

Sure, but maybe somebody need just that for their DPO project repair project. PSU, interface board, chassis parts are still custom Tektronix stuff, not that commonly available.
Burnt resistors that were there originally near the dead ASIC felt apart during cleaning and troubleshooting. I have no time nor desire to store this unit, waiting for lucky day, and rather give it up to hands of more motivated/equipped hobbyist, at cost.

[MadTux]

Looks like a nice Louis Rossman job (with good margin if sold), if someone manages to find another broken one cheaply.  Otherwise expensive paperweight.

It also might help if you remove the heat sink from the broken ASIC, so people can read the number and see wether their broken scope has some similar ASICs

[max-bit]

ADC Board DEAD
That can not be fixed ....

Total value practically zero

[Zucca]

ADC Board DEAD
That can not be fixed ....

Total value practically zero

 

https://www.eevblog.com/forum/buysellwanted/fs-(usa)-broken-tektronix-dpo7104-(adc-failure)-for-parts-or-repair/msg1350930/#msg1350930

[bloguetronica]

I've bought this scope as parts condition for listed above price.

If you know where to buy DPO7K scope (be it new, or used) for less than 7K$, let me know, I'd like one MSRP for this unit even without 2SR option is >20K$.

If you have donor ASIC chip/board, experience in repair probably this is very repairable, as other parts of the box are working good.
But you already know this by now. 

Hi TiN,

Well, IMHO, you just made an horrible deal. How are you imagining one of us repairing that front-end? Requires BGA soldering, maybe? And troubleshooting will be a nightmare (I imagine it is not just the ADC, but other more things that need repair/replacement).

If it was working, or needed minor repair, I would say you've had a great deal. But the scope is useless. Sorry! It is what it is.

To add, you'll be lucky if you find a replacement board that works out of the box. And by the way, at a good price.

Kind regards, Samuel Lourenço

[_Wim_]

I must say that I really appreciate how TiN listed this.  He made very clear what the problem was, and as he suggested, their might be someone for who this is just what they need (although unlikely)

He could also have listed this on Ebay just as "broken", and many of us would be tempted to give it a try hoping for a power supply issue or something else that is an easy fix. But by clearly stating what was wrong, he limited his changes to get his own investment back.

[nctnico]

I must say that I really appreciate how TiN listed this.  He made very clear what the problem was, and as he suggested, their might be someone for who this is just what they need (although unlikely)

He could also have listed this on Ebay just as "broken", and many of us would be tempted to give it a try hoping for a power supply issue or something else that is an easy fix. But by clearly stating what was wrong, he limited his changes to get his own investment back.

I agree. OTOH a buyer would feel cheated if he/she found out the oscilloscope has been opened before and is impossible to repair without donor parts.
It has happened to me before in the past. I bought a hi-end CRT monitor with a defect. The seller sworn to me no repair attempts had been made. When I opened it up several connectors where loose and there was clear evidence someone tried to repair it. After some e-mailing back & forth the seller admitted his guy couldn't fix it. Ofcourse I got it going again but the bad taste remained.

[Old Printer]

I must say that I really appreciate how TiN listed this.  He made very clear what the problem was, and as he suggested, their might be someone for who this is just what they need (although unlikely)

He could also have listed this on Ebay just as "broken", and many of us would be tempted to give it a try hoping for a power supply issue or something else that is an easy fix. But by clearly stating what was wrong, he limited his changes to get his own investment back.

I agree. OTOH a buyer would feel cheated if he/she found out the oscilloscope has been opened before and is impossible to repair without donor parts.
It has happened to me before in the past. I bought a hi-end CRT monitor with a defect. The seller sworn to me no repair attempts had been made. When I opened it up several connectors where loose and there was clear evidence someone tried to repair it. After some e-mailing back & forth the seller admitted his guy couldn't fix it. Ofcourse I got it going again but the bad taste remained.

That is clearly not the case here, the seller has been open about the exact nature of the problem. From here it is up to the buyer to judge the difficulty of the repair, or whether it is worth the risk. Dave

[bloguetronica]

I must say that I really appreciate how TiN listed this.  He made very clear what the problem was, and as he suggested, their might be someone for who this is just what they need (although unlikely)

He could also have listed this on Ebay just as "broken", and many of us would be tempted to give it a try hoping for a power supply issue or something else that is an easy fix. But by clearly stating what was wrong, he limited his changes to get his own investment back.

Indeed. At least he was honest about the problem. Anyway, "broken" items on eBay are always suspicious. The best way to filter these is to ask the seller for photos of it working or not working. It is a mistake to ask what is broken beforehand. Then you can judge yourself if it is worth buying or not.

But, nevertheless, repairing BGAs is impossible to the average user (speaking by myself). It is not the kind of repair to be done inside a kitchen oven (like those guys that heat Xbox motherboards that way to "fix" them for a time). But I guess that oscilloscope is not for the average user either.

Kind regards, Samuel Lourenço

[charlyd]

Just a question did someone ever checked the option key from the above Post #1 (right picture) on the DPO7104 2SR option??  with the options keygen tool circling arround.

check post #1 carefully..  to see there is no typo.  the option 2SR is a hardware option. and then the mismatch is generated?

[calibrationfixture]

Hi,

For a DPO7054 C010362 Option 2SR I got no CRC Mismatch. For Option 2SR the Option Masks First Digit is 8.

And for a DPO7054 B021197 Option 2SR I got this:

This Key is for UID 1B8E000052CD (S/N 21197, model TDS/DSA/DPO7254)
CRC Mismatch?

Calibrationfixture

[langlv]

I saw that the generated string is longer with B021197 unit, that means the option string was longer (more 00 at the end). May you retry with same option string as with C010362?
Hello from Switzerland .

[kissmu]

Just a trick:

Try to generate code with all option FF FF FF FF....
You will got the all possible and impossible option.

It takes me lot of time, but it works.

If possible you will got the 2SR option too. (the first FF on/off it) If you have only 2 ADC than the maximum is 20GS/s

But i lost my eeprom content, so i lost the possibilty of apply any options.
But my DPO7054 transformed to DPO7104 with default settings. the bandwidth limits went off. It is not bed, but i cant use the signalvu anymore.

So if somebody have DPO7104 eeprom please help me.
here is the this chip: https://www.eevblog.com/forum/index.php?action=dlattach;topic=318913.0;attach=1457488;image

[kissmu]

here is my original post:
https://www.eevblog.com/forum/repair/tek-dpo7104-looking-for-flasheeprom-content/msg4105765/#msg4105765