The TR-7 transceiver was originally designed to transmit on all bands between 1.8Mhz to 30Mhz. However the transmitter was disabled from transmitting outside the established Amateur Radio bands with an inhibit circuit on the Digital Board. To work around the inhibit circuit Drake produced the AUX-7 Board accessory. This board would allow out of band transmitting with a programmable IC module setup for the proper band. Out of band 500Khz segments was then accessible by selecting the programmed mo

DRAKE TR7 DDS VFO ( digital vfo)