>
>
>
>On Sun, 21 Feb 1999 08:22:49 -0800 Rich Measures <measures@vc.net>
>writes:
>>Carl said:
>>>
>>>Which is why 100K is the suggested max in any literature I have seen
>>>for bleeders.
>>
>>Ä References, please. . In a typical 8171 anode-supply, a 100k-ohm
>>bleeder would dissipate 810 watts.
>
>I suggest you read the original post which had nothing to do with your CB
>tube. Neither was a single 100K bleeder mentioned in my reply since the
>160W dissipation is too close for comfort in a 200W resistor, which could
>lead to premature failure..
>
? You stated that 100K is the suggested max in any literature you have
seen. What literature?
>
>>
>>>>>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 apiece of
>>>>>perfboard and be done with it.
>>>>>
>>>>>Absolute YUK ! 800K to 1M bleders..no way Jose.
>>>>>
>>>>? What is to be gained by using a 200k-ohm bleeder on a C-filter,
>>Carl?
>>>
>>>Quicker HV bleed down time, less chance of a recharge.
>>
>>Ä What mechanism recharges the capacitor?
>
>
>An incomplete discharge. Something very easy to do for an inexperienced
>person..
>
? Bzzzzzt. You said recharge.
>>
>>> All my concerns are safety related and for others not well versed
>>in PS issues.
>>>
>>>A string of 3W does not offer much of a voltage breakdown safety
>>margin.Matsushita not a common distributor item and similar wattage
>>Panasonic, etc are only 350V.
>>
>>Ä The manufacturer's (Panasonic/Matsushita) rating at 70 deg. C
>>ambientis 500v or 3w . For a 100k-ohm unit, the realizable
>>dissipation is 2.5w at 500v. .
>
>Lets see, what supply are you working with at this moment? The original
>post or an 8171 ? You drift around too much trying to make a point that
>suits the instant.
>
>BTW, the DigiKey catalog rates the Panasonic/Matsushita 3W at 350V,
? In the current catalog, the max. v rating of the 1w, 2w and 3w units
are all 350v. This is not logical since the film path in a 3w unit is
not the same as a 1w unit. . Previous catalogs listed the Panasonic3w
units at 500v max.
>would put a string of 10 over the ratings in a 4KV supply and would be
>insanity at 7500V.
>
>Of course, someone recommending an 8171/4CX10000D on the ham bands ( at
>least in the USA) is not exactly all there anyway.
? _____ .
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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