Unfortunately I already deleted the email, so my apologies as I can't quote
who pointed me to that resistor!! But my friend you were spot on with that
assessment. No handbook could have given me that type of firsthand
experience. Many years of amp building and repair gives you that!
73,
Scott
----- Original Message -----
From: "Ian White GM3SEK" <gm3sek@ifwtech.co.uk>
To: <amps@contesting.com>
Sent: Sunday, March 01, 2009 2:36 PM
Subject: Re: [Amps] HV Divider
>
> A few minutes ago, I wrote:
>>
>>So you have a voltage divider with 10M in the top leg and two 100k
>>resistors in parallel (for safety) at the bottom. So the no-load voltage
>>at the divider tap has got to be 2380V x 50k / (10M + 50k) = 11.84V.
>>
>>
>>IF all the resistors are of the correct values, and are also wired
>>correctly, and you do have 2380V connected to the top end, then there
>>WILL be 11.84V at the tap, plus or minus a few percent.
>>
>>That would be exactly as designed, to provide a "HV OK" signal to the
>>Triode Board.
>>
>>We're also presuming that the B-minus rail is closely tied to chassis...
>>yes?
>
> Apparently no. Scott reports an open-circuit resistor from B-minus to
> ground.
>
> Having fixed that, he's now seeing 11.68V from the divider, which is
> within 1.4% of the expected value.
>
> Many thanks to whoever pointed Scott towards that resistor. Normal
> one-to-one support for the Triode and Tetrode Boards continues on
> another channel.
>
> (Rick, I'll be right with you.)
>
> --
>
> 73 from Ian GM3SEK
> http://www.ifwtech.co.uk/g3sek/boards
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
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