[Elecraft] OT: Astron linear PS regulation issues

[Kevin McQuiggin (SFU)]

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

Sent from my iPad

> On Feb 25, 2019, at 17:29, <john at kk9a.com> <john at kk9a.com> wrote:
> 
> Who makes a better linear power supply, especially large ones?
> 
> John KK9A
> 
> Fred Jensen k6dgw wrote: 
> 
> I've given up on Astron despite the fact that many people say they never 
> have troubles.  Apparently, Astron does not have a supplier for inside 
> star washers for screw/bolt connectors, I've found almost crumbly, 
> crystallized cold solder joints on the point-to-point wiring terminals 
> [in one case, it wasn't soldered at all], and often the case is not 
> bonded well [or at all] due to paint and/or no star washers.  These are 
> all basic steps in quality electronic construction, there's just no 
> excuse for it.
> 
> 73,
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
> 
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