I bought a Rackmount 35amp Astron when I started working at my office (the office bought it). We turned it on in 1993 and it is still on today. I have a 50 amp at home that besides the crappy meter lights (they now are illuminated by LEDs!), runs like a champ.
Funny though, when I find a supply with the -VDC tied to chassis ground, I always pull it - some Astrons do and some don't. All of our other linear supplies float (HP, QJE, Acopian). Keeps ground loops at bay! 73, Hank K4HYJ -----Original Message----- From: elecraft-boun...@mailman.qth.net <elecraft-boun...@mailman.qth.net> On Behalf Of Randy Farmer Sent: Monday, February 25, 2019 10:24 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] OT: Astron linear PS regulation issues I have two recent vintage Astron RS-35M units. They still use the exact same 723-based regulator circuit that they have used for thirty years or more, so the design hasn't changed. What **may** have changed is the build quality. I carefully inspected both of mine right after taking delivery. I made sure the green wire from the AC cord was securely bonded to the chassis and checked for obvious soldering problems. I also tied the negative output line to the chassis. They have both been running like trains 24-7 for the last three years or so. The only failures I've had (on both units) are the stupid internal meter lamps. 73... Randy, W8FN On 2/25/2019 8:36 PM, Kevin McQuiggin (SFU) wrote: > I have a ~30-year old Astron 13.8 VDC 20-amp supply that I got when it was > retired from a project at work. I used it for low current applications for a > few years, then it went to storage for about 5 years. > > One of the two power transistors failed a few months ago and this took out > some other components. I had put it back into service in a 5-10 amp > application. I figure that the failure was likely just due to age and the > fact that the supply had been in storage for a few years. > > I replaced both of the power transistors, two blown diodes, the > electrolytics, and a couple of ICs and other components, and the supply is > running fine again. Solid output at 10 amps load. > > Given its age I am extremely happy with it. The internal quality and > components seemed good, but that may have been due to its > design/manufacturing era. Not to sound like some old codger, but perhaps > designs aren’t as robust as they used to be. > > Kevin, VE7ZD ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html