SRS620 schematics are on ko4bb.com Didier KO4BB
Sent from my BlackBerry Wireless thingy while I do other things... -----Original Message----- From: John Ackermann N8UR <j...@febo.com> Sender: time-nuts-boun...@febo.com Date: Fri, 23 Mar 2012 14:46:07 To: <j...@quikus.com>; Discussion of precise time and frequency measurement<time-nuts@febo.com> Reply-To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Subject: Re: [time-nuts] Anyone familiar with SR-620 repair? Great advice. I have the manual, but it doesn't include schematics. I think someone on the list has a PDF of the schematics, so I'll be digging around for that before I start digging into the box. John On 3/23/2012 2:36 PM, J. Forster wrote: > Not w/ that instrument, but try the following. I assume you have the book > w/ schematics. > > Power the unit and with a DMM or VOM check the PS rails to see which is sick. > > From the book, locate all bypass caps on that rail. > > Put your DMM across each in turn. The one with the lowest drop is likely > the culprit. If there is more than one w/ low voltage, it's likely the one > closest to the power supply. > > You might try touching all the bypass caps to see if any are runni9ng hot. > This does not always work, because zero voltage or zero current dissipates > nothing. > > -John > > ============== > > > > >> My SRS SR-620 counter died last weekend. After superficial >> troubleshooting, it looks like there's probably a short on one of the >> power supply rails. Symptom is that nothing lights up when power is >> turned on, but one or more of the three terminal regulators gets very, >> very hot (can't tell which one since they're all bolted to the side rail >> as heat sink). The unit had been running continuously for several weeks >> when the failure occurred. >> >> I just learned from SRS that they charge a flat rate 25% of the current >> list price for repairs! (To be fair, if you're the original purchaser, >> it's only 20%.) The SR620 currently lists for about $5K, so we're >> talking about a mighty expensive shorted cap (if that's what it is)! >> >> Anyway, has anyone here troubleshot an SR-620 with a problem like this, >> or have any general insights about working on one of these beasts? >> >> Thanks, >> >> John >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.