[Test-Equipment] Same old dumb question my way:

[Richard Knoppow]

    I've used incandescent lamps as dummy loads many times but 
beware they are not constant resistance. Tungsten has a 
significant positive temperature coefficient so the lamps start 
out low resistance and get higher as they heat up. The practical 
problem is that the cold resistance as measured with an ohm meter 
may be pretty far off from the hot resistance which is probably 
what you get as a dummy load, unless its a very high wattage bulb.

On 5/3/2022 6:30 PM, Doug Hensley wrote:
> Guys I will remeasure these tomorrow.  i used one of those little
> Chinese microprocessor controlled L/C meters.  I have an older
> Sencore meter which I should have used.  I will also put my Rig Expert
> analyzer on it and see what it says.
> 
> Regardless of what I get, the baby that was tossed out with the
> bath water was the question when loading an old rig prior to putting
> it on the antenna, I could not see any difference between tuning up
> on the light bulb or tuning up on the Ohmite cluster?  This was
> especially true when I inserted a little LDG box in the train.  Dipping
> the plate & peaking the grid felt identical either way.  Once switched
> over, there was no need to change those settings.
> 
> Doug W5JV
> 
> 
> 
> 
> 
> Visit https://www.qrz.com/db/W5JV for some great vacuum tube finds.
> 
> 
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-- 
Richard Knoppow
1oldlens1 at ix.netcom.com
WB6KBL