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Author Topic: Rigol DS2072A Not Powering Up  (Read 2301 times)

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Offline Andrei

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Rigol DS2072A Not Powering Up
« on: January 18, 2015, 04:19:02 AM »
Hi,

About 6 months back I got a Rigol DS2072A and immediately hacked it. It worked with no issues for a few months, after which I did not have time to use it much.

Today, I go to power up the scope (the green LED on the power button is pulsing on/off) but the scope would not turn on. Before I take the screwdriver to it to start debugging, I was wondering if anyone had a similar experience with their scope.

I can't imagine anything past the power button is broken, maybe the soft switch is not making good contact, as the power supply seems to be lighting up the LED.

Any ideas on what I should look at first? Based on posting this in the Test Equipment forum, this does not seem to be a very common problem.


Regards,
Andrei
 

Online wraper

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Re: Rigol DS2072A Not Powering Up
« Reply #1 on: January 18, 2015, 04:34:24 AM »
Is there any way that you can send it for warranty repair? Guess you've got it from somewhere abroad. The issue is that while there could be just some trivial fault, unrepairable faults are possible too. Therefore if there is warranty service possible, I would advise to not to destroy warranty sticker. Not easy to remove undamaged but possible.
 

Online wraper

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Re: Rigol DS2072A Not Powering Up
« Reply #2 on: January 18, 2015, 04:38:14 AM »
Quote
I can't imagine anything past the power button is broken, maybe the soft switch is not making good contact
If you can think that it is that simple, would not recommend to repair it by yourself at all. Conductive rubber buttons don't fail like that.
EDIT: I would even say that it is very bad that power button is lighted. That means that power supply probably is  OK and there is a fault somewhere on main board.
« Last Edit: January 18, 2015, 05:28:08 AM by wraper »
 

Online wraper

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Re: Rigol DS2072A Not Powering Up
« Reply #3 on: January 18, 2015, 05:27:41 AM »
I have looked on the power supply photo and it seems that there actually is main and standby PSU on the PSU PCB. Therefore if main PSU failed, power button will light up but oscilloscope won't switch on.
 

Offline Andrei

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Re: Rigol DS2072A Not Powering Up
« Reply #4 on: January 18, 2015, 05:37:06 AM »
Hi wraper,

Thanks for your response.

I have already started inquiring about the possibility of returning this thing under warranty for repair. I bought it from TEquipment.net, which is located in the USA, but it is unclear whether or not they are an "authorized distributor". I have sent them an email and will wait for their reply before doing anything too drastic.

That being said, if it turns out that I cannot get the scope repaired under warranty, my only option may be to pay for the repair, and if the cost does not make sense for the price of the instrument, attempt to take a look myself.

Would you be able to point me to the photos you are looking at for the PSU, are they Dave's hi-res photos from his videos? I can track those down myself if that is the case.

Any further debugging/next steps insight would be appreciated.
 

Online wraper

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Re: Rigol DS2072A Not Powering Up
« Reply #5 on: January 18, 2015, 06:01:56 AM »
Quote
I bought it from TEquipment.net, which is located in the USA, but it is unclear whether or not they are an "authorized distributor"
They are. If you are in US (according to your nickname, maybe Russia?), there is no point to repair it yourself. Only if you have to do expensive overseas shipping. I wrote photo but actually watched video  :). On the 8th minute. Main power is enabled by optocoupler, there are 3 of them in one place. Power button pads are directly on the main PCB.
« Last Edit: January 18, 2015, 06:27:30 AM by wraper »
 

Online wraper

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Re: Rigol DS2072A Not Powering Up
« Reply #6 on: January 18, 2015, 06:26:12 AM »
If you decide to fix it by yourself, first thing to do would be to check if enable signal from the main board is present on the PSU PCB. Likely optocoupler closest to the the side of the PCB (among 3 of them)  is responsible for enabling main PSU. That would be the place (or at the connector) where to measure if enable signal is present. If it is present when pushing power button, but no voltage appears on the PSU output, then check for the fault on PSU primary side. If there is no enable signal, likely there is a fault on the main board.
 

Online wraper

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Re: Rigol DS2072A Not Powering Up
« Reply #7 on: January 18, 2015, 06:34:31 AM »
Just highest probability. Of course you would need to check where actually traces go.
 


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