The original reasoning for having a floating negative was to allow 2 of the
supplies to be connected in such manner so as to provide a bipolar voltage
configuration.
And yes, they were RF prone without the negative being connected or bypassed
to the chassis. The 3rd pin AC connector was the only ground source
originally.
73
Bob, K4TAX
----- Original Message -----
From: "Mike Hyder -N4NT-" <n4nt_m_o_hyder@charter.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Saturday, July 30, 2005 5:59 PM
Subject: Re: [TenTec] Astron RS-35M and Omni VI
> Of course, I don't know why he did it but can suggest one possibility.
> The
> RS-35 was prone to RF interference which entered the supply by way of the
> negative output. In the early RS-35 supplies, the negative post was not
> connected to the chassis but was connected to a pin of the regulator IC.
>
> If Dave was troubled by RF adversely affecting his supply, perhaps the
> resistor cured the trouble. Astron suggested grounding the negative post
> to
> the chassis for the same reason but many never got word of that
> suggestion.
>
> 73, Mike N4NT
>
> ----- Original Message -----
> From: "Bill Tippett" <btippett@alum.mit.edu>
> To: <tentec@contesting.com>
> Sent: Saturday, July 30, 2005 12:50 PM
> Subject: [TenTec] Astron RS-35M and Omni VI
>
>
> I am still in the process of selling
> N4SU's radio gear for his XYL. Dave had
> an RS-35M which he used to power his
> Omni VI along with some other things.
> He has a 720 ohm power resistor (15W
> I think) across the output terminals.
>
> Does anyone know why Dave
> might have done this? I assume it could
> be to help prevent surging when equipment
> is turned on but am wondering if there is
> some other reason. Any ideas?
>
> 73, Bill W4ZV
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
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