Actually I don't even have a panel meter for HV yet, I just have to get the
output from the divider string down to 12v or less to provide the HV OK
input to the Triode Board.
I have to work on it some more and see if there is another problem in the
power supply somewhere. Another email suggested it might be the safety
resistor from the HV B- to chassis ground. I will have to desolder that and
check its value as there is no numbering on it that I can see. It's an old
wirewound vitreous type, left it in place because the amp was working before
modifications.
73,
Scott
----- Original Message -----
From: "Bob Maser" <bmaser@tampabay.rr.com>
To: "KB0NLY" <kb0nly@mchsi.com>; <amps@contesting.com>
Sent: Sunday, March 01, 2009 1:54 PM
Subject: Re: [Amps] HV Divider
> If you are using a 0-1ma FS meter it is typically 1000 ohms per volt.
> This
> means that if you wanted a 2500V FS reading you would need 2500 * 1000 =
> 2,500,000 ohm in the meter multiplier string. I would think that you want
> a
> FS higher than 2500V, like 5000V, which would mean that you need 5,000,000
> ohms or 5 meg ohms in the meter multiplier string. Then you need
> something
> to lift it slightly above ground, like 10K ohms.
>
> Bob W6TR
> ----- Original Message -----
> From: "KB0NLY" <kb0nly@mchsi.com>
> To: <amps@contesting.com>
> Sent: Sunday, March 01, 2009 7:47 PM
> Subject: [Amps] HV Divider
>
>
> I'm using GM3SEK's Triode Board for my 6m amp project using the GI-7B, i
> ran
> into a problem today with the power supply. According to his manual, i
> sent
> him an email as well waiting for a reply, for 2500v i should use 10 1M Ohm
> resistors in series from the B+ line, on the end of that string of
> resistors
> there is also two 100k 1W resistors to chassis ground. My supply is
> 2400V,
> measured with a HV meter i get 2380V.
>
> The problem is the output of that divider is supposed to be 12v or less.
> I
> put the positive of my meter on the end of the chain of resistors and i
> put
> the negative to chassis, 0V, nothing nada. Then i put the negative to the
> 0V lug on the secondary of the transformer and i get 113V.
>
> How is this supposed to work that i can get 12v from it?????
>
> 73,
>
> Scott KBØNLY
>
> _______________________________________________
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> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
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