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TW Electronics 1958 - 2000

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TW2 (2m) Transmitter

The TW2 transmitter (photos above) was the first bit of amateur radio equipment that TW produced and started selling in 1960. It was a crystal controlled, valve AM/CW transmitter for the 2m band with an RF input of around 10-15watts. It used a QQVO3-10 in the P.A. stage and was modulated by a pair of EL84s.

A separate TW matching power supply was available that provided the HT and heater supplies via the 'plug' on the rear of the TW2. The Belling Lee socket on the rear was for the microphone (crystal mic) connection and the 'locked' potentiometer to its left was the microphone gain control.

The crystals used (one supplied with the rig)  were around 8MHz (for x 18 multiplication) but I do know that some amateurs used 6MHz crystals (for 24 x multiplication). A lot depended on what was available on the 'surplus' or 'ex W.D' market at the time.

The 'innards' of the TW2 are shown above. The photo (right) shows some modifications (red circle)  that have been carried out at some time in the past  when a crystal socket to accommodate larger crystals e.g 10XJ variety was added next to the HC6U socket. That said, this radio is very 'clean' considering its age.

The early TW2 units had cases that had much tighter bends at the corners as shown in the photograph below left (courtesy of Tony Pugh GW8ASD) rather than the much neater 'rounded' corners shown on the unit at the top of this page . This particular unit has had the crystal socket changed at some stage. The unit in the photograph below right (courtesy of Tom Withers G3HGE) shows the original 'prototype' TW2 transmitter.

I have acquired another TW2 transmitter (complete with the matching power supply (see last photo here).  It is in remarkable condition considering its age as you can see from the photos below.