> In marine transmitters all coils I have seen were
> silverplated. My understand is that
> 2-3 mikron was used, whatever that is in medival terms.
> 73 Rag LA5HE
As I recall 1 micron is 40 microinches [OK 39.39 microinches]. That would
mean a 2 micron layer is 80 microinches or 0.00008 inches - about 50 times
less than the "Highly polish-able" grade silver plating.
It would seem the plating is for either cosmetic or anti-corrosion purposes.
Either way most of us can rest easy once again after this technical
exchange. Maybe there is merit in silver plating all of the junctions in the
tuner and antenna system. That might allow compression fitting that have
lower resistance over a longer term than some folks have. I doubt it is
worth the trouble.
*****************************
To get an idea of "what a difference a dB makes", download a copy of
Audacity [a free program] and install it. Then take a .wav file and listen
to it for a brief period. Next reduce the audio playback level by 1 dB
[Audacity has calibrated output so you can do this]. Listen again. Do this
several times reducing the audio level until you can actually hear that
there has been a change.
The change you heard was in an audio stream that had no QRM and no QSB.
Carefully ask yourself, "at what point will someone picking up my
transmissions be able to discern that I added 1 dB to my emitted signal".
Audiophiles learned long ago that adding the last octave to their systems
would cost 3 to 10 times the cost of the initial system --- antenna systems
are not much different. Getting an additional 3 dB really costs a bunch
[some money and a lot of time] after you have a 1.5 KW amp and a good
vertical.
Tod, K0TO
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|