Instead of purchasing old equipment (very few will come with new battery pack...repairs either expensive or not available), you could always use two radios - one for RX and one for TX. Or use a scanner on RX!

And on the FM birds, it is not mandatory to operate at full duplex. Preferable, but not mandatory.

I use the Yaesu FT-60R for all my AO-51 demonstrations. The underlying "theme" to my presentations is the fact that most hams probably already have the necessary equipment to work the FM birds, and, if not, it doesn't take a lot of money for equipment. FT-60R are great dual-band rigs: bulletproof construction, strongest belt clip of ANY amateur HT chassis on the market, 1,000 memories, RX 108 to a gig, great RX volume. Add to this a great battery system where, with the optional AA battery case, you have FULL TX POWER available if needed. For comparison, use an optional AA case with the Kenwood TH-F6a, and you're running one-half of one Watt TX.

The FT-60R can be programmed for "split freqs" (page 28 of the owners manual) - where you can set it up to TX on one band and RX on another in a single memory location. (Several other current HTs do this, too.)

All for under $200. Improve its -2dB stock antenna, and you have a portable satellite station!

For AO-51, I have mine programmed like this ... (nothing extraordinary here) ...

Ch 100, RX 435.310, TX 145.920 Ch 101, RX 435.305, TX 145.920 Ch 102, RX 435.300, TX 145.920 Ch 103, RX 435,295, TX 145.920 Ch 104, RX 435.290, TX 145.920

Channel 102 is the "center" frequency. As you ACQUIRE the signal, listen slightly ABOVE (ACQUIRE - ABOVE: my mnemonic device) the center frequency to compensate for the doppler effect.

Preachin' to the choir here ... sorry ... (grin)

Clint Bradford http://www.clintbradford.com