The R. L. Drake model TR-4 is a single sideband transceiver designed for the transmission and reception of upper and lower sideband signals on the 80 through 10 meter amateur bands. AM and CW capabilities are included. Its compact size makes it ideal for both fixed station use in conjunction with our model AC-3 120 volt AC Power Supply, or for mobile installations using our model DC-3 12 volt DC Power Supply. The 300 watt P.E.P. input on SSB enables the TR-4 to give an excellent account of itself "barefoot" and it will drive the highest powered ham linear amplifiers. Upper and lower sideband selection is accomplished by switching between two 9 me crystal lattice filters with 2.1 KC passbands. Among the other features included on the TR-4 are VOX and PTT on SSB and AM, diode detection for AM, shifted carrier CW, automatic transmit receive switching on CW, built in CW sidetone, separate RF and AF gain controls, solid state VFO with linear permeability tuning, transmitting and receiving AGC indicator and plate ammeter/RF output indicator, adjustable pi-network output, and built in crystal calibrator. The addition of the accessory RV-4 remote VFO speaker combination enables the operator to receive, transmit, or transceive throughout the band being used without distrubing the setting of the TR-4 tuning dial. This is useful for working DX stations operating outside the United States phone bands, or for working near your own frequency in search of a clear spot under crowded band conditions.