----- Original Message -----
From: "HAROLD B MANDEL" <ka1xo@juno.com>
To: <marc.wullaert3@pandora.be>
Cc: <amps@contesting.com>
Sent: Friday, March 17, 2006 6:47 AM
Subject: Re: [Amps] DRAKE L7 Plate meter update 2 and now PS
> Dear Marc,
>
> They might be bleeder resistors.
Or they could be load resisters like the two 75K 55W type used
in the NCL-2000. They get wicked hot and sit above the vents from
the filter caps below. Kind of a chimney effect. At 3kv they dissipate 60 watts.
>
> With just the HV supply running and the tubes not conducting, the
> bleeders are across the HV output.
>
> I run 100K ohms at 200 watt resistance on a 3.5 ~ 4.25 KV supply
> and it gets warm.
>
> Last year I built a supply using 100K at 50 watts, 4 pieces in series,
> and one of them failed and I accidently touched the HV+ beehive
> stud 1/2 hour after shutdown and I was belted across the room!
>
> Do the math. Measure what your HV is and calculate the
> amperage and wattage going through the resistors.
>
> You might want to consider an upgrade in devices if they are
> cooking during operation.
>
> Hal
> W4HBM
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> On Fri, 17 Mar 2006 11:15:56 -0000 "Marc Wullaert"
> <marc.wullaert3@pandora.be> writes:
>> Hi ,
>>
>> The plate meter whas resoldered and it is working.Probely a bad
>> joint
>> Now when running the amp in standby the R9 and R10 (50k-50watt)
>> They running hot and give a burning smell after a time .Checked
>> time
>> visual but seem's ok.I already cleaned out the dust from the ps.
>>
>> What is the job of this resistors ?Could they be removed from the
>> power
>> suplly
>> or it is best to replace them with others ?
> _______________________________________________
Mike k1ern
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