Henry measured the high voltage across only ONE capacitor in the string.
(The cap closest to ground) Check your manual to be sure.
Replacing the caps will most likely fix the issue. And as said before, make
sure the amp is wired for 240 volts before plugging it into 240 volts!
73
Jim W7RY
----- Original Message -----
From: "Bill, W6WRT" <dezrat1242@yahoo.com>
To: <amps@contesting.com>
Sent: Saturday, December 12, 2009 4:53 PM
Subject: Re: [Amps] Excessive Plate Voltage Henry 2KD-5
> ORIGINAL MESSAGE:
>
> On Sat, 12 Dec 2009 12:14:12 -1000, "Roland AH6RR"
> <Toesonnose@hawaii.rr.com>
> wrote:
>
>>
>>Aloha All,
>>I have a Henry 2KD-5 that has been sitting for a few years and after doing
>>some repairs and tube replacement I turned it on and the plate voltage
>>went to 4000V before I could turn it off. One of the filter caps smoked
>>and now 1 has a short they all seemed hot, they are the orignal filter
>>caps. I plan on replacing the all but I want to know if this will cure the
>>problem. I checked the HV supply wiring and it is fine. Should I look at
>>anything else?.
>>Roland AH6RR
>
> REPLY:
>
> That is a bit strange, but here is how I would approach the problem.
>
> First of all, make sure you are not applying 240 VAC with the tap on the
> transformer set for 120 VAC. Assuming that's ok, after replacing the caps,
> put
> the amp on a variac and bring up the AC slowly. It is fairly likely the
> excess
> voltage problem is in the meter circuit, namely a resistor that changed
> value.
> Check for that first. Your HV may actually be ok. Go from there.
>
> 73, Bill W6WRT
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>
>
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