[Amps] every db lost re Tubes vs. Solid State

[Jim Brown]

On 4/30/2012 4:10 PM, Mike Waters wrote:
> In any case, it's been proven that the length of the impedance bump inside
> the junction of a PL-259 and SO-239 is such a tiny fraction of a wavelength
> below 200 MHz that losses from a mismatch is of no practical concern,
> either for RX or TX.

Yes. Several years ago, a VE1 (RGB, I think) sent me a copy of 
measurements he had done on a bunch of PL259s and barrels in a string. 
His data showed VERY low insertion loss to fairly high frequencies.  A 
few years ago I had built a bunch of coax cables for a DX trip using 
Commscope 3227 (like LMR400, but #10 solid copper center), all with 
PL259s. . To test them, I spliced them together with barrels, then 
measured the loss with HP gear by the substitution method.  There were 
about 25 PL259s and half that number of barrels in the run.  All were 
Amphenols, and there was 1300 ft of cable in the run.  The loss at 500 
MHz (the lowest frequency at which the cable loss was specified) was a 
few dB less than the mfr's spec for the cable.

73, JIm K9YC