Hi Dave, Thanks for the info. I've already built the analogue supply and it's working fine. It's interesting that even that 55W supply is operating near it's -15V limit with the 58503A and the minumum load requiremen on th main +5V rail is not quite met either.
Robert. > On 08 November 2018 at 21:43 "Dr. David Kirkby" > <drkir...@kirkbymicrowave.co.uk> wrote: > > On Thu, 8 Nov 2018, 14:53 George Atkinson via time-nuts < > time-nuts@lists.febo.com mailto:time-nuts@lists.febo.com wrote: > > > > Last month I was at the UK “National” hamfest and in the flea > market area a seller had a HP 58503B for sale. It was missing the cover and > power supply (AC mains version)including mounting. However it was only £3 > (<5$) so it was a no-brainer to buy it. Research shows that PSU failure is > fairly common on these units. > > > > > > I had the PSU fail in my 58503A. It keeps trying to start, then stops. I > have checked capacitors with an ESR meter, but could not fix it. > > Three is a good chance your unit takes the same PSU. If so > > > https://www.ebay.co.uk/itm/BEL-POWER-MAP55-4003-55W-Quad-Output-Embedded-Switch-Mode-Power-Supply-SMPS/132833037734 > > may be of interest. I had an offer of £45 accepted yesterday. > > Those power supplies can often be found up to £300 on eBay, but Arrow > Electronics sells them new at £120. > > > Dave. > > > > > > > _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
