The FRDX400 receiver dates from the early 70's. It is a hybrid valve/transistor design to cover all of the HF amateur bands 160m,80m, 40m, 20m, 15m,10m,plus 6m and 2m using two interal transistorised convertors. At the time therewas not 6m band allocation in the UK so the unit sold here were recrystalled for the UK 4m band. The main receiver used valves in the signal path but the VFO was solidstate and The frequency dial was calibrated in 1KHz steps. To cater for VHF use the receiver also had an FM discriminator fiited along with squelch control. The VFO out was available externally along with muting function to allow it's use with the matching FTDX 400 transmitter. Four crystal filters were provided as standard for narrow band CW, SSB,AM and FM bandwidth. Size 37cm wide, 19 cm high, & 32 cm deep. It's heavy!