A modded Cossor 54

[`FRANK.C]

This is a TV that I picked up and I thought it was interesting how the controls were moved to make room for a magnifier. The magnifier is long gone.
Two of the controls were moved down and the other two were put on brackets so they could be access from the sides. The original holes were crudely filled.
They must have been moved fairly early in its life as there is a lot more ware to the cabinet around the new positions compared to the original positions of the controls.

Frank

[Murphyv310]

Hi Frank.
Your first prewar TV?
No doubt you'll return it back to its original condition. The depth of the set is a reminder of the length of the CRT and why mirror lids were used so much.
Have fun.

[ppppenguin]

Was this electrostatic deflection? If so that's inevitably narrow angle as the electrons hit the plates if you deflect them too far.

[`FRANK.C]

Hi Trevor
I am just contemplating what to do at the moment. If I go ahead with it it will be my first restore in a number of years.
It looks complete. The cardboard tubular EHT cap's have been changed for  Visconols.
I don't think it will be an easy one. As can be seen in the photos there is a lot of green rot. So I would expect that at least some of the transformers will probably need rewinding.
The getter on the CRT has for the most part gone milky but there are some blobs of silver left so they may be some hope.
I will do some checks on it to see if there is any emission. There would be not much point in proceeding if it is a dud.


Hi Jeffrey
Yes you are correct is is electrostatic deflection.

Frank

[boater sam]

Any 'scope tubes that could be used?

[peter scott]

I wonder if a VCR97/517 might be an easy replacement if the CRT has gone to air?

Peter

[`FRANK.C]

HI Sam and Peter
I have seen mentioned that the VCR97 might do but I have never seen one fitted, yet. I sure I have one somewhere and maybe one or two others of a similar size.

I have tested the CRT and there is some emission.
The heater in intact and draws very close to 1A with 4V across it.
With 10V across the grid and cathode it drew around 400uA.
With the grid and cathode strapped together I put 3KV from a high impedance source across the cathode and final anode and it drew approximately 110uA.
Nothing visible on screen.
There is some emission, whether it is enough I am not sure.


Frank

[peter scott]

Hi Frank,

With your 3kV set-up try the trick I learnt from Jac of holding a magnet near the final anode and move it about and see if anything comes into view.

Peter

[`FRANK.C]

Hi Peter
Thanks for that tip I hadn't heard of it before. If I understand correctly I think I would need to remove the mu-metal shield on the neck of the tube before I could try it.

Frank

[peter scott]

Perhaps just apply the magnet in the bell portion after the mu metal screen.

P.