Repair of HP8648 Signal Generator

[mitslo76]

Hi Everyone,

My HP8648A just died. Magic smoke went out  . Apparently it's power supply unit, that produce +15,-15,+5 and +38V... I want to try to repair it, but I have two problems. I couldn't find Schematic and also some resistors and one diode near to HV MOSFET IRF840 burned out so I couldn't read values. I was wondering if someone has schematic or at least if someone can take photo of similar unit so I can begin from replacing burned parts. Building totally new power supply is I guess an option too, but as last resort I guess. Any help is more that welcome. Thanks in advance.

Best Regards,
Slobodan
 

[lowimpedance]

 I t would seem that HP only suggested whole assembly repairs in the service manual  .
If you have not seen this thread it 'might' be of some use ! .
https://www.eevblog.com/forum/repair/video-teardown-and-repair-of-an-hp-8648c-synthesized-signal-generator/msg152221/#msg152221
good luck

[mitslo76]

Thanks for the link. Actually I saw this tread but as you noticed the HP Operation and Service Guide doesn't have a schematic, they recommend module change... I was thinking since is of the shelf part (its Computer Products Power Supply 510160) maybe someone has the schematic...

[Unrockstar]

Hello,

I repair my Powersupply at this time too,

I shot a photo and Upload it tomorrow.

Can you make a Photo from your Supply?

My Powersupply doesn´t power up correctly after repair.
I think i have make a Mistake by a wrong restistor