Keysight 34470A Front Panel PCB Repair

[alexm271175]

Hi,

I have a 34470A. It does not boot when I turn the power on. I found in the service manual that in this case a frequency on the front panel PCB (TP200) should be testet. If it is not correct, change the front panel PCB for something about 350 euros...

In my case there is no frequency on this test point. Before I will order a new PCB I would like to ask if maybe someone had the same problem and found the defective part?

best regards
alex

[HighVoltage]

Did you measure all DC rails for correct voltages and low ripple first?
Just to make sure the front panel gets the correct supply?

[Smith]

I had an 34465A which would not boot (similar build I guess). The front panel had a short on the lower 10uF multi layer caps, I think there where about 5 of them in parallel. One of them had shorted, in this case there was no fuse, so the transformer burned up. Replaced both and the unit is working again.

You have to take out the front panel, they are placed near the connector to the main board if I remember correctly.