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Electronics => Repair => Topic started by: Rariusz on July 05, 2017, 01:22:02 pm

Title: Fluke 192 - problem with oscilloscope
Post by: Rariusz on July 05, 2017, 01:22:02 pm
Hello,

I have Fluke 192 oscilloscope and I have problem with oscilloscope.
More specifically, multimeter work but oscilloscope does not work.
Did anyone have a similar problem and can help me solve the problem?

Best,
Rariusz
Title: Re: Fluke 192 - problem with oscilloscope
Post by: welpester on July 05, 2017, 01:25:45 pm
Hi

I do not have that meter, but i think you must give more information so someone could help you.

-welpester
Title: Re: Fluke 192 - problem with oscilloscope
Post by: Rariusz on July 05, 2017, 01:40:47 pm
Hi,

Ok, Using my fluke 192 i can measure for example voltage and also the rest of parameters however I cannot see the waveforms on oscilloscope.
In oscilloscope the waveforms is zero.

Best,
Title: Re: Fluke 192 - problem with oscilloscope
Post by: Armadillo on July 05, 2017, 02:07:21 pm
Do the probe calibration, any waveform?
Title: Re: Fluke 192 - problem with oscilloscope
Post by: welpester on July 05, 2017, 06:38:25 pm
Service manual:

http://assets.fluke.com/manuals/192B____smeng0100.pdf (http://assets.fluke.com/manuals/192B____smeng0100.pdf)

Probably silly question, but is probe the and coupling set correctly?

-welpester
Title: Re: Fluke 192 - problem with oscilloscope
Post by: PA4TIM on July 05, 2017, 07:25:10 pm
How did is stopped working ? What did you do to it ?
The channels are isolated from each other so if you did not blew up the first channel and then the second, the channel asics will be good. The fault will then be where both channels use the same circuit.

Connect a test signal to a channel and follow it with a scope until it disappears. It goes to the channel asic, via an opto and transformer to the Sample-asic. From there to the ADC and then to the Digital Asic. But the latter controls the rest so lot of chances to run around in circles.

Be careful with the display and backlight connectors and flatcables because  you need to "split" the case and measure on both sides of the PCB and turn pcb and display/front-case at the same time without damaging the connections.

They are a pain in the @#$ to repair, the D-asic is often a bga and the asics are expensive.