on 3/4/00 1:06 PM, Tom Rauch at w8ji@contesting.com wrote:
> You say a sharp pulse of VHF current heats the resistor from the
> inside out, while a longer HF current heats the resistor and
> severely damages the outside.
>
This also flies in the face of understanding how resistors work. A 2 Watt
resistor can handle a peak power of many times that of 2 Watts. With the
milliseconds of time that Rich is talking about, there is no way that the
resistors could get overpowered and burn out from VHF energy. Considering
that the gain of the tube is much less at VHF than at HF and considering all
of the other factors of power supply capability, etc., there is no way.
If anyone doubts me, take your two meter radio and a let's say a 5 Watt
resistor and hook them up. Key up your radio (at full power) and let it go
immediately. You won't damage the resistor nor even make it warm. And
you'll likely have keyed into it for at least 250 to 500 mS which is much
longer than Rich's 10s of mS.
73,
Jon
KE9NA
-------------------------------------
Jon Ogden
KE9NA
Member: ARRL, AMSAT, DXCC, NRA
http://www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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