Wireless sets No. 19 MK ll - 1942

[Mike K]

I have a friend here , who is a radio tech by trade , and an avid, fanatical even , collector of WW2 radios . Some years ago he took a 19 set to his workplace to test it out on a hugely expensive spectrum analyser .

The results would have your local radio inspector having fits .

The main problem with them is , the PA tuning is so coarse , its so easy to tune the PA dial to the wrong side of the actual freq . you are after . The mixing process in the chain of stages before the final 807 , produces quite a few different products and you can easily transmit 455 khz away from where you think you are. By moving the PA dial slightly ( about 1/16" ) you are actually moving a whole lot in terms of resonance . You get false dips all over the place on the PA current .

The mk2 set draws about 140 watts with everything on , you get around 4 watts of RF carrier on average from the A set . Not that efficient really .

The designers, PYE UK , admitted the set had shortcomings from the start . It was put into service in a hurry during a period when the war was going badly . Get em out , and into the lines .

Here the MK 2 version is the most common , mk3's are rather scarce . The mk 3 was an attempt to improve the efficiency in terms of power consuption . The Canadian Mk3 has the vibrator RX supply , whereas the British Mk3 has 2 seperate genemotors , one for tx and one for rx. The set has gained a reputation , more by word of mouth than anything else . Basically , there were so many of them made

In a shack , resting on a table , with a freq. meter with you , they are OK to use . Try netting out in the field with no freq. standard ...... big problems await you .

Iv'e had enough of them ......

Mike