>
>Rich says:
>
>>? References, please. . In a typical 8171 anode-supply, a 100k-ohm
>>bleeder would dissipate 810 watts.
>
>>>>>If I wanted a Reliable bleeder for a 4kV C-filter supply, I would
>>>>>series up 8 to 10 Matsushita/Panasonic 100k-ohm, 3w MOF resistors >on
>a
>>piece of
>>>>>perfboard and be done with it.
>>>>>
>
>I'm puzzled. 810 watts dissipation in 100K means 9kV across it. That seems a
>bit high for the 8171.
>
? The rating for A-zero emission is 7500VDC. I ran mine at 9100v-No
load / c. 7800v under ssb modulation. I have heard that 10kV no-load is
ok for ssb service. At the AM rating, the peak anode supply potential is
10kV under 100% modulation. .
>If the 3w MOF resaistors are rated at 500volts, 10 of them give you 5kV, and
>that's a hell of a lot less than 9kV.
>
? In that amplifier I used a 40k-ohm 10w R across each of the 20
electrolytic filter caps.
This was before I tested Matsushita's MOF resistors. For example, a
100-ohm 3w rated unit will dissipate 12w for one-hour with little ill
effect.
- cheers, Peter
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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