I can confirm what Jean-Louis is saying as I have had the same problem with a lot of SS equipment of the same vintage. The high capacitance low voltage capacitors were totally open. Usually though, that lowered the raw DC voltage so much that the regulation circuit would not even work. Regards - Mike
Mike B. Feher, N4FS 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jean-Louis Oneto Sent: Wednesday, May 02, 2007 6:29 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] 5087A Distribution Amplifier Hi Brian! Last time I had this problem, it was the VERY BIG capacitor (1500MFD - 40VDC) which measured as 21.8pF (yes PicoFarad!!!) Jean-Louis Oneto OCA GEMINI - Avenue Copernic - 06130 Grasse - France Tel: (+33)[0]493.40.53.80, Fax: (+33)[0]493.40.53.33 e-mail: [EMAIL PROTECTED] ----- Original Message ----- From: "Brian Kirby" <[EMAIL PROTECTED]> To: "Time Nuts" <time-nuts@febo.com> Sent: Wednesday, May 02, 2007 9:54 PM Subject: [time-nuts] 5087A Distribution Amplifier >I bought an HP 5087A distribution amplifier off of ebay. "The unit is > in good working condition". Funny the power supply is putting out 120 > hertz square waves.....which makes all the outputs look like they are > oscillating garbage....disconnecting the power supply from the load does > not change the situation. I subbed a test power supply and the > amplifiers work fine. > > Does anybody have the schematic to just the power supply and could I > bother you to scan it and send to me, or a link to get it, or the manual ? > > The power supply looks very simple, but the schematic sure makes life > easier ! > > Thanks in advance - Brian N4FMN - [EMAIL PROTECTED] > > > _______________________________________________ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
