new killer scope in town - a true game changer from R&S - RTB2002 & RTB2004

[Robaroni]

Hi everyone,

The fine/coarse adjustment stopped working on my RTB2004, it's just fine now. I checked the rotary encoder switch and it works so I'm thinking there's a board problem. My guess it's the control board where the encoder is situated but trying to get anything out of R&S is futile, worse they won't sell you a board if indeed that's the trouble.
It's, of course, out of warranty.

Anyone run into this and what was your solution?
Thanks for the time and help,
Rob

[Rydda]

@Robaroni
If your post refers to the problems you had with the FFT setup, I really doubt that there is a fault in your scope.
In FFT mode:
- in the FFT window the horizontal controls sets the 'Center Frequency' and the 'Frequency Span'.
- in the signal window, only the 'Horizontal Position' and the 'Time Range' (with RBW disabled) can be set. The 'Time Scale' cannot be set, so the control may appear to be inoperative.

[Robaroni]

Thanks, now that I'm thinking about it, it's probably the horizontal control that's stuck in fine that's causing the FFT problems. So if you have an FFT bandwidth of 100 megs or more like I did, the control will take forever to get to the audio frequencies.

[Robaroni]

Thanks Peter.
I can change the horiz. pos. bringing up the horiz. control window, the button seems to be the problem. Not the knob itself but the chip that it drives. Is there a reset for this scope? I haven't really played with that stuff, just using the scope for my decoding and other apps. Maybe I should try and reload the latest firmware?

[Robaroni]

Thanks for the info.
I tested the encoder, it's pretty basic - push the button you either get an open or a short on the internal switch which I do get. If it's a board problem it would be relatively easy to find if I had the schematic. I guess I could look at it under my stereoscope and see if there's a bad solder point on an FPGA or something, I doubt an ASICs or an FPGA went bad but you never know.
After a lengthy conversation with the tech at R&S I found out they don't have access to schematics, only the service dept. does. Some newly implemented edict from Germany apparently. Maybe someone should tell them you can get a Rigol 12 bit resolution scope for three hundred bucks now!

She was kind enough to give me the board number and price - $190 but I need a dealer to buy it they won't sell it to me.

[pdenisowski]

After a lengthy conversation with the tech at R&S I found out they don't have access to schematics, only the service dept. does. Some newly implemented edict from Germany apparently.

I've been with R&S for over 15 years and it's always been that way:  even service manuals don't necessarily have detailed, component level schematics (the RTB2000 service manual does not - I have it in front of me).

Maybe someone should tell them you can get a Rigol 12 bit resolution scope for three hundred bucks now!

Oh, we know -- I spent part of the day yesterday meeting with our oscilloscope product management team in Munich : )

But frankly, there's a lot more to a scope than the number of ADC bits.

(Munich HQ was still open and operating despite record snowfall in Munich last wekeend )

[Robaroni]

I'll tell you what, I just bought the Rigol 12 bit DHO924s as a back up for eight hundred bucks. It's packed with everything down to bode plots and is extremely well made. I can see things in the waveforms I can't see on my RTB. Okay so it doesn't have a 10" display but I love the form factor and it's a ball to play with. I even tried decoding and the probes don't look any worse then the RTB's which two have died in the five years I've owned it, I've had Tek scopes for years without losing probe signals or functions. Now the horizontal coarse/fine died and I can't even buy a board for it, if in fact it is the board and not some FPGA on the main board. Unfortunately I can't find out because your tech dept. doesn't even have basic schematics that trouble shoot down to board level. It's always been that way? Maybe you shouldn't have told me that, I think end users should have the right to repair with schematics and access to parts, it's not a good omen that your tech dept. doesn't even have schematics.

You have the schematic? Great, so it's not the switch on the horizontal rotary encoder, what does that switch feed? Is it on the FRONTCONTROLLER FC-2A40 (Part #: 5810.2111.40) board? Maybe you can tell me what pin so I can check continuity. Thanks!

So they referred me to your service dept. and it might as well have been a robot, I get it you want me to send my scope in for repair, what's that going to cost? I lost the connection and she never called back or emailed me with costs. I get it again, we're small potatoes.

They worked in a snow storm because they know they're in trouble and have to find solutions, they got upstaged again by China. Maybe they should invite me to their board meeting, I'll be happy to tell them how the bear went through the buckwheat.

So tell me why I shouldn't get a bigger Rigol for my next scope? That's rhetorical..... are you sure you want to have this conversation?

[Martin72]

I can see things in the waveforms I can't see on my RTB.

Maybe they don't even exist.

[Robaroni]

The 924 has a lower noise floor, check Dave's video.

Look, this is the future, chip designers make heroes out of everyone, we can expect better and better quality instruments.

[goaty]

Can we get the RTB2k service manual please ? I tried unsuccessfully logging into gloris.
I can send serial number of device with foto if that´s needed.
Thanks, Thomas

[nctnico]

Thanks for the info.
I tested the encoder, it's pretty basic - push the button you either get an open or a short on the internal switch which I do get. If it's a board problem it would be relatively easy to find if I had the schematic. I guess I could look at it under my stereoscope and see if there's a bad solder point on an FPGA or something, I doubt an ASICs or an FPGA went bad but you never know.

Problems like these are easy enough to find without a schematic as front panel controls are typically constructed as an x/y matrix using diodes and switches. Just look at the signals to check the logic levels; you can use the oscilloscope itself to test this. It could be something simple like a bad connection or bad solder joint on a diode or something like that. Maybe the problem is already fixed by disconnecting the cable to the front panel and connecting it properly again. I have fixed these kind of problems without having schematics several times.

[Robaroni]

The simplest solution is a schematic showing the control pin. Come on R&S this is a six year old machine, I seriously doubt anyone wants to steal your circuits.

Nctnico, I tried the connector trick, I could probably try following the traces but honestly I would rather not unless I have to. I remember when Keysight had actual service manuals, I have  few from older stuff. I think there's one around here from the famous 34401A meter now that I think of it. I still use that meter and it's still perfect.

[pdenisowski]

@robaroni  I'd like to start out by saying that I'm sorry you're unhappy with your service / support interaction.  If you'd like, please PM me and I'll send you my direct email address - I can't promise that I can do everything you ask, but I can guarantee that you'll be in touch with someone who is very happy to get your feedback and pass it on to the responsible parties here at R&S.

Unfortunately I can't find out because your tech dept. doesn't even have basic schematics that trouble shoot down to board level. It's always been that way? Maybe you shouldn't have told me that, I think end users should have the right to repair with schematics and access to parts, it's not a good omen that your tech dept. doesn't even have schematics.

Just curious:  have you tried getting schematics for current products from Rigol or other T&M instrument manufacturers?  I would be very interested in seeing them.

So they referred me to your service dept. and it might as well have been a robot, I get it you want me to send my scope in for repair, what's that going to cost? I lost the connection and she never called back or emailed me with costs. I get it again, we're small potatoes.

Again, please PM me with your information and I will find out what happened and speak to whomever you spoke to.  Assuming this is North America, I personally know everyone in our technical support center, and they are all very customer-focused professionals.

They worked in a snow storm because they know they're in trouble and have to find solutions, they got upstaged again by China. Maybe they should invite me to their board meeting, I'll be happy to tell them how the bear went through the buckwheat.

We actually just had a record year

I have regular conversations with everyone on our scope team, including product management, sales, marketing, development, etc.  I can assure you that any feedback you provide me with will be carefully listened to.

So tell me why I shouldn't get a bigger Rigol for my next scope? That's rhetorical..... are you sure you want to have this conversation?

Yes, I very much want to have this conversation.  Feedback from customers (even unhappy customers) is very important to us and drives almost everything we do at R&S.  As both someone who has worked in test and measurement for almost 30 years as well as an avid electronics hobbyist, I very much understand your frustration and would also very much like to see if there is something we can do to address it.

[Robaroni]

pdenisowski
Thank you for your time and concern, I do appreciate it. The woman in the tech dept. truly tried to help me but she had no schematic and no access, she did however find the board the rotary encoder was on and did pass that on to me although, again, I have no avenue to purchase it if indeed this is the problem. The service dept. was useless.

Here's an example of a current instrument I own, I found the service manual with a simple Google search and copied the link within less than 30 seconds:

https://www.keysight.com/hk/en/support/34465A/digital-multimeter-6-5-digit-truevolt-dmm.html

Direct me to the link for the RTB2004 Service Manual, I have yet to find it.

As for the scope itself, I thought it was buggier than my Tek 2024B, the RTB probes were poor quality and the Tek scope was trouble free. My other instruments from several other major manufacturers have all been more dependable and less buggy than the RTB.

I'd be interested to see how your banner year compared to China's, banner years are relative terms. How many instruments you sold and how well they hold up and perform are two entirely different commodities.

Bottom line would I buy another scope from R&S - no. In fairness I'm semi-retired now so I probably won't make too many more major purchases although I will probably make another scope purchase not counting the backup I just bought.

You said you're looking at the schematic, okay tell me what IC the rotary encoder coarse/fine pin terminates on. Simple, this will tell me if I'm on the right board and I'll know if it's a bad IC or connection.

Thank you for your time and help, again, I do appreciate it.

[Hydron]

The front board has it's own firmware - I'd be very confident that the IC reading the inputs is on that board not another.

[Robaroni]

The front board has it's own firmware - I'd be very confident that the IC reading the inputs is on that board not another.

Thanks, that helps, it was my suspicion. I may put it under a microscope and see where the encoder lead comes out.

[Lino22]

In the manual there is a note about the divider factor of the probe with AC coupling. Why should the voltage be different than with DC coupling? Is there an explanation for this?

Peter

User Manual v11 - Page 50

4.1 Connecting probes and displaying a signal
...
No attenuation of passive probes with AC coupling:

If AC coupling is set, the attenuation of passive probes has no effect, and voltage is applied to the instrument with factor 1:1. Observe the voltage limits, otherwise you can damage the instrument.


Edit:
Maybe the coupling capacitor is directly at the socket, even before the 1 megohm input resistor?

I am sorry for being back to this. I just want to make sure i understand.

>> I have a probe with only a 10M resistor in series, no divider. When i use it to connect a signal with both AC and DC element to RTB2000, then:

1. AC coupling
The DC part will be "stopped" by the input capacitor, and the AC part will be attenuated  10:1.
If the DC is massive, it can burn the input as it will be transferred across the probe with no attenuation.

2. DC coupling
There is no capacitor on the input, and so both AC and DC will be attenuated 10:1 at the input.

>> Now, i have a P6015A probe that has its own internal 1000:1 divider , and parasite capacity 1pF across the 1000M series resistor in it and 2pF on the input to the ground.
I measure 25kV /1us body/1ms cycle pulses from a magnetron pulser, and the probe is inserted between the pulser and the magnetron (right on the cathode) and connected to RTB2000.
There seems to be a difference between AC and DC coupling, as the DC coupling seems to load the pulser more and makes it drop out.
Do you guys have any idea why?

[egonotto]

Hello,

with a divider probe you must use DC-coupling.

Since a coupling capacitor has an extremely high impedance at DC, practically the entire input voltage at the coupling capacitor drops at DC. This can be very unhealthy.

See the circuit in the picture Divider.png.

Best regards
egonotto

[Lino22]

Hello,

with a divider probe you must use DC-coupling.

Since a coupling capacitor has an extremely high impedance at DC, practically the entire input voltage at the coupling capacitor drops at DC. This can be very unhealthy.

See the circuit in the picture Divider.png.

Best regards
egonotto

I am afraid that it is more like this. So the input impedance the signal right after the probe can see is largely set by the 100k resistor.

[EEVblog]

Unfortunately I can't find out because your tech dept. doesn't even have basic schematics that trouble shoot down to board level. It's always been that way? Maybe you shouldn't have told me that, I think end users should have the right to repair with schematics and access to parts, it's not a good omen that your tech dept. doesn't even have schematics.

Just curious:  have you tried getting schematics for current products from Rigol or other T&M instrument manufacturers?  I would be very interested in seeing them.

So would I. I don't know of any scope manufacturer who has released schematics in probably the last 25 years.
Siglent for example do service manuals, which is fantastic, but there are no schematics:
https://siglentna.com/download/6149/?tmstv=1702895353

[2N3055]

Hello,

with a divider probe you must use DC-coupling.

Since a coupling capacitor has an extremely high impedance at DC, practically the entire input voltage at the coupling capacitor drops at DC. This can be very unhealthy.

See the circuit in the picture Divider.png.

Best regards
egonotto

I am afraid that it is more like this. So the input impedance the signal right after the probe can see is largely set by the 100k resistor.

If we are  being pedantic upper resistor in divider would be circa 99,9 MΩ and lower circa 99,9kΩ... 

But I think egonotto was talking about first probe you mentioned not the P6015A ...

[Lino22]

But I think egonotto was talking about first probe you mentioned not the P6015A ...

Oh of course.

[Robaroni]

Unfortunately I can't find out because your tech dept. doesn't even have basic schematics that trouble shoot down to board level. It's always been that way? Maybe you shouldn't have told me that, I think end users should have the right to repair with schematics and access to parts, it's not a good omen that your tech dept. doesn't even have schematics.

Just curious:  have you tried getting schematics for current products from Rigol or other T&M instrument manufacturers?  I would be very interested in seeing them.

So would I. I don't know of any scope manufacturer who has released schematics in probably the last 25 years.
Siglent for example do service manuals, which is fantastic, but there are no schematics:
https://siglentna.com/download/6149/?tmstv=1702895353

Dave,
First, he told me he was looking right at the schematic and wouldn't even tell me if the encoder connected to a chip on the same board. You'll notice that the person who said "he was very much interested in this conversation" never got back to me. (I did see he was quick to give you a thumbs up though!)

Here's a link to the Agilent 33220A from 2012 with a full service manual and a schematic (the 33220A was discontinued in 2016 BTW):

https://www.keysight.com/us/en/assets/9018-04439/service-manuals/9018-04439.pdf

Here's a current production 34465A service manual:

https://www.keysight.com/hk/en/support/34465A/digital-multimeter-6-5-digit-truevolt-dmm.html

And a service manual for the Tek TPS2000B scopes.

https://download.tek.com/manual/077044700web.pdf

I haven't checked any other instruments but these were quick searches, do a search for an RTB 2004 service manual.

R&S doesn't even offer a service manual on a scope that has been out over 7 years. Ask them about buying parts, I've directly bought parts from Tex and Keysight (Agilent). They won't even sell you parts.

Their own tech dept. specifically told me they don't have access to schematics, search down, you'll see people still looking for a schematic around here. Their service dept. was only interested in one thing - send it in for repair.

R&S, I'm going to tell you again - here comes China. That's why you guys are burning the midnight candle in snow storms. I just bought a fully loaded 250M 12 bit scope for eight hundred bucks that's pretty darn good and well finished to boot.

I'll ask you again - are you sure you really want to have this conversation? I remember when Japan went after VW in the 70's and the VW dealer laughed at me, then I remember when Japan went after MB with the Lexus and Germany laughed.......

[edavid]

First, he told me he was looking right at the schematic and wouldn't even tell me if the encoder connected to a chip on the same board.

No, he never said he had the schematics.  Here is his exact quote:

I've been with R&S for over 15 years and it's always been that way:  even service manuals don't necessarily have detailed, component level schematics (the RTB2000 service manual does not - I have it in front of me).

He has the internal service manual, which has no schematics.

[Robaroni]

Okay, thanks for the clarification, I stand corrected but that doesn't change the fact that their tech dept. doesn't have schematics AND probably never has AND they don't have service manuals AND they won't even tell me if the encoder drives a chip on the same board AND they won't even sell me a part if it does!