> Actually ... if properly installed, the insertion loss for
the 'barrel
> connector' is less than .5 db ... that has been addressed
here before.
Actually the HF loss is negligible. Even the worse barrel
connectors I've seen have insignificant loss at HF.
.5 dB is over 10% loss, and at that loss even 100 watts
would cause significant temperature rise. (It takes about 5
watts of loss applied for a minute to make a connector feel
warm, and 10 watts of loss would be pretty toasty.) A .05dB
loss connector would become pretty warm in operation with
1500 watts of CW operation.
I think what we consistently do is misplace the decimal
point. .01dB loss at upper HF would be more typical for a
typical connector, with .05dB reserved for the worse. A good
way to look at this is heat. Heat is the real area of
concern when you run more than a few hundred watts, not
loss. If you are running a kilowatt and the connector isn't
melting, the loss is probably insignificant.
UHF connectors are almost impossible measure with direct
measurements, because loss was so low. I generally measure
them by using temperature rise at HF, but the short and
sweet explanation is if they don't melt they are probably
OK.
73 Tom
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