Resistor Appeal

You may have heard of us already. We are rebuilding a W.W.II cipher breaking machine called a Bombe at Bletchley Park. We are now about three quarters of the way through our rebuild with the mechanical section virtually complete and most of the wiring in place.

We are now tackling the relay area where many resistors are used. We have most of these but one type has eluded us until recently. We have been looking in the area of general electronics and punched card equipment but to no avail. Then, an ex STC member of our team said that these looked like telecoms resistors. A quick investigation revealed that what we were in fact looking for were

Resistor Coil Number 12, 600 ohm non-inductive.

Now we are trying all known sources to see if we can locate 110 of these. Can you or any of your colleagues help in any way please?

We realise that trying to get hold of so many at the same value might be expecting too much but if we had the bobbins from other values we are prepared to rewind them. Initially we need 26 in a few months time so that we can start preliminary testing. We have longer for the rest.

There are images of similar items but not of the correct value on our WEB site at the end of page

www.jharper.demon.co.uk/appeal2.htm

The diameter is approximately 15/16" and the height a little over 5/8".

If you could help or put us in touch with somebody who can we would be very much obliged.

All the best

--
John Harper

If you can help, please contact Rob White or John Harper direct.