Six tube rig with VFO
by OH6DC
Top left:
3.5 MHz VFO using ECC85 and EF89 tubes. Circuit is based on "McCoy VFO" by W1ICP (QST February 1962). The VFO is stable after warm-up of about 30 minutes.
Bottom left:
A separate high voltage power supply for the VFO. Eliminates all chirp in TX signal.
Center top:
3.5 MHz CW transmitter using EL84 and EL86 tubes. Circuit is based on 1950's novice transmitter, as described in a Finnish book "Uusi radiokirja" by Osmo A. Wiio and Unto V. Somerikko (1958).
Center bottom:
A dummy cabinet. I wanted the transmitter in line with the VFO and receiver. By the way, all cabinets are made of recycled PC power supply boxes. A piece of aluminium sheet was glued to cover holes in the front panel.
Top right:
3.5 MHz receiver using ECC85 and EL86 tubes. Cicuit is based on "The Regen-o-flex receiver" by Dave Schmarder.
Bottom right:
High voltage power supply for TX and RX.
Inside view, from left to right: VFO, TX, RX.
I built this rig in year 2012 and used it in a Finnish homebrew rig event called "ITE-tapahtuma".