On American three pin plugs the SMALLER blade is hot.
> Date: Thu, 29 Jan 2015 05:06:42 -0500
> From: k8ri@rogerhalstead.com
> To: amps@contesting.com
> Subject: Re: [Amps] Astron Power Supply replies
>
> Check your voltage "TO" the pass transistors. If it's high the
> transistors will run hot. IIRC the VS and RS use the sane control
> circuit, but it's been quite a while since I had one apart.
>
> Please NOTE the Green wire is not neutral! It is a true ground, or
> "earth" connection. Never, ever treat it as neutral. Your power cord
> should also have a green.ground / earth AND a neutral (White) wire. If
> it is one of the newer modular cords, it goes to the round pin below the
> hot (larger blade) and neutral (smaller blade) . I don't know if the
> newer Astrons are using those cords, or are still using direct wired
> power cords.
>
> 73
>
> Roger (K8RI)
>
>
> On 1/28/2015 9:50 PM, Gary Smith wrote:
> > Gentlemen,
> >
> > Thank you all so much for the replies regarding upgrades, suggestions
> > and green wire dealings with my two Astron power supplies. The only
> > reason I asked that here was the mention of the green neutral being
> > left in a floating condition on at least some of the Astron PS. I
> > need to repair the one that is Kaput and am looking around for a
> > LM723 around here as the links mention that to be a common culprit,
> > I've used them before in several projects and probably have several
> > gathering dust in an old Radio Shack package. If not, I see them
> > listed quite inexpensively on ebay and will pick up several for
> > future issues I may encounter.
> >
> > The four 2N3771 transistors really do run hot on the VS-35M, can't
> > say I touched them on the RS-35M but surely they are the same, the
> > circuit between the two PS are very similar. I'm assuming I can use
> > any off the shelf 2N3771 & the .05 5W wirewounds will balance them
> > fairly. On the PS I made some years back I used 3055's and I have
> > several of them unused, would these be more rugged or should I stick
> > with the 3771 as it comes with?
> >
> > Mention was made of Arctic Silver; I have some Arctic Silver 5 & some
> > of their Ceramique which I too used in overclocking computers. I can
> > certainly remove & replace the heat sink compound with this, not a
> > big job and using it did lower my core temps on the computer
> > processor.
> >
> > I really appreciate the links and help.
> >
> > Thanks & 73,
> >
> > Gary
> > KA1J
> >
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