Wireless set 109

[Mike Kelly]

Following on from Neil's article , with the WS 109.

Another simple but effective design. These sets are very easy to repair as all of the components are within easy reach , this is a unusual feature for a WW2 military wireless set . Around 1500 was the total production 1939 to 42 , making these sets comparatively rare .

I have used a 109 set on the ham bands and it's a good performer with the transmitter having three 807 valves and a xtal or VFO drive. The VFO is tuned by a rotating coil arrangement , rather than a split air capacitor , the VFO takes a while to settle down but it is not too bad. The AM modulation is strong being plate modulated .

The power supply units changed over the production run , some have four 6X5GT tubes as a full wave rectifier setup . The power source is a 6 Volt lead acid battery.