Rap 'n Tap
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From: David Norcross
Date: 3/7/03
Time: 11:00:44 PM
Remote Name: 64.4.130.218
I seem to recall that Modern Radio Labs used to carry Pal products... I'll see if I can dig out an old catalog of Elmer's.
This website says "Pal" is a trade name for Crosley (not sure if it is equal to Pal Radio Corp): http://www.gbronline.com/radioguy/trdirp.htm
From: Steven Coles
Date: 3/30/99
Time: 10:20:14 PM
Remote Name: 207.149.222.126
Short lengths of wire have about 29 nH per inch according to one source I use. That's assuming you measure the wire end-to-end. However, antennas don't act like a length of wire with a radio frequency (RF) generator at one end and a receiver at the other. An antenna acts more like an open-ended transmission line. It's capacitive up to 1/4 wavelength, then inductive to about 1/2 wavelength. The antenna impedance's resistive component increases linearly from about 36 ohms for a 1/4-wavelength antenna to about 800 ohms for a end-feet, 1/2-wavelength antenna. Check the base resistance and reactance charts for various antennas in an antenna engineering reference book. (You could also calculate the numbers yourself using a second-semester electromagnetism book and a large slash of vector calculus.) Whatever the charts show will be modified by non-ideal installation (coupling to nearby objects, ground not perfectly conducting and not perfectly flat). Antenna impedance's resistive component is necessary to getting energy out of the transmitter's field and into your radio. It also knocks the Q way down and ruins the selectivity. That's the theory. Not knowing any better, I tried something like you're talking in the forth grade. The selectivity was really poor, but otherwise it worked.
Steven