|
Hi George,
toggle quoted message
Show quoted text
Thanks for your kind advices, I know the difficulties of working on switching power supply...have been in electronics the past 44 years, and sure, I do prefer repairing linear ps! Now, I am retired, but always trying to repair equipments for friends...sometimes, it's a real challenge! 73, Roland F8CHK -----Message d'origine-----
De?: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...] Envoy¨¦?: lundi 17 juillet 2017 15:56 ??: hp_agilent_equipment@... Objet?: Re: [hp_agilent_equipment] Re: 8590B power supply problem Hi Roland I have been following this thread from the start. In my experience you stand little or no chance of finding a true schematic, what you need to do is to find someone who knows how to repair SMPSU's and has the facilities for doing so. You can only really fault find on them when they are fully energised by the incoming mains supply. This requires specialist skills and precautions coupled with a safe working environment. There are lethal voltages present (370VDC at very low impedance) also a simple mistake can result in the SMPSU going into total self destruct mode. 73 George G6HIG ________________________________________ From: hp_agilent_equipment@... <hp_agilent_equipment@...> on behalf of roland.etienne@... [hp_agilent_equipment] <hp_agilent_equipment@...> Sent: 17 July 2017 11:42 To: hp_agilent_equipment@... Subject: [hp_agilent_equipment] Re: 8590B power supply problem Hi Tom, I have the same power supply as yours and it's a faulty one also...I wonder if you sojve your problem and if you could identify fhe HP900 component ? I also think that it is an optocoupler, but not sure at all! It's a pity we can't find the exact schematics of this power supply! My primary circuitry looks fine, have made some tests connecting 12 v from an external power supply so the NE5560 is running, signals seem to be OK on the buck regulator and the DC-DC converter. So may be the problem is in the feedback?? If you have any infos, I thank you in advance! 73, Roland F8CHK ------------------------------------ ------------------------------------ ------------------------------------ Yahoo Groups Links |
