Trio JR-310 and TX-310 restoration project

I got Trio (now Kenwood) JR-310 and TX-310 SSB receiver and transmitter pair recently. When it comes to me both receiver and transmitter are in very bad shape and most of the PCBs and chassis are covered with dust and some of the components are very badly damaged. After examining both the chassis I decided to repair both units because of its vintage value (and also I like to try some tube base SSB receiver and transmitter pair).

Trio JR-310 is AM, SSB and CW mode HF receiver. This receiver has 3.5, 7, 14, 21, 25 and 50MHz operating bands and sensitivity is around 1µV. This receiver consists with 6 vacuum tubes, 5 transistors and 19 diodes. JR-310 which I restored is working with 110V and total power consumption is around 70W.

Bottom view of restored JR-310 receiver

TX-310 is 20W SSB transmitter and designed to match with JR-310 receiver. It is capable of LSB, USB, AM and CW transmissions in HF bands. This unit consists with 10 vacuum tubes, 5 transistors and 9 diodes. Like JR-310, this unit also working with 110V power source.

S2001 final stage vacuum tube and high voltage area of TX-310

I did restoration of above mentioned TX-310 and JR-310 step-by-step and most of the steps are listed in my qsl.net pages.

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