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Old November 4th 03, 06:55 PM
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Default T2DF + diplexer = HF + LF coverage, AM BC rejection

One of my strange ideas...

1) There used to be an expensive T2FD by RF Systems that could be
remotely switched to T configuration for receiving use below 3 MHz

2) If one wants to cover 0.1-0.54 and 3-20 MHz or so, a diplexer may
allow using two specialized antennas with one coax.


Aha!
{bulb lighting up 'n mah noggin}

- 4 LPF's (Fc = .55 MHz) with cold sides joined together (one for each
of the upper and lower arms of the T2FD) feeding in-phase an un-un,
LF-optimized, stepdown RF transformer

- a balanced HPF (fc = 2 MHz) feeding a bal-un, HF-optimized, stepdown
RF transformer

- a low-Z, LF-HF combining diplexer + one coax, or maybe two separate
feeds for HF and LF...

Result: one antenna for both LF and low MF (Tee) and HF (T2FD), AM BC
rejection, no remote switching needed, possibly usable for HF QRP
transmitting.


Comments?


If you are wiser than me, tell me where to read up!

TIA

Filippo