This is the radio that was installed in some L-2, L-3 and L-4 aircraft at Ft. Sill. Bc-721 (SCR-585). This radio uses the fixed antenna.
http://www.ebay.com/itm/271092269972?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
http://www.ebay.com/itm/271092269972?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
http://www.ebay.com/itm/271092269972?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649