Post by elorens on Apr 15, 2023 17:45:46 GMT 12
Generally (not always) I can fix vintage radio electronics, but sometimes a mechanical problem will defeat me. I have an Ultimate CVU I have been working on. The dial cord was broken, and I have replaced it as shown in the image. I have not been able to find a cord layout diagram for this model, but I think I have it about right. The cord runs over a brass drum connected to the tuning capacitor. The drum is grooved, a bit like a worm gear. The cord runs through a gripping mechanism on the tuning knob shaft, shown in the second image. This has a springy strip which I think is supposed to press the two discs together so that they grip the cord. There is also a single spring in series with the cord.
The whole thing ALMOST works, but frustratingly, not quite! I can make the dial pointer move a little way along its track, and the capacitor moves accordingly. But it is not possible to tune across the whole scale. I turn the knob, but nothing moves.
I suspect the cord gripping mechanism, but I can also see that the cord does not sit neatly in the grooves of the brass drum: it tends to cross over itself, which may make it harder for the mechanism to work.
Has anyone worked on something like this? Can anyone suggest any ways of making it work? Thanks! Lawrence
The whole thing ALMOST works, but frustratingly, not quite! I can make the dial pointer move a little way along its track, and the capacitor moves accordingly. But it is not possible to tune across the whole scale. I turn the knob, but nothing moves.
I suspect the cord gripping mechanism, but I can also see that the cord does not sit neatly in the grooves of the brass drum: it tends to cross over itself, which may make it harder for the mechanism to work.Has anyone worked on something like this? Can anyone suggest any ways of making it work? Thanks! Lawrence
