GEC " Gecophone" BC2001 a little help please
 

I've just acquired one and a half GEC BC2001's I need help with the following firstly Valves what I have are toast as per usual what can be used as a substitute that's relatively easy to get hold of ??

Secondly I have everything with the exception of the plug in reactance unit could anyone provide measurements Photos and values to enable me to make one please.

Thirdly does anyone have scans of the instruction labels fitted to the insides of the doors please.

Any help greatly appreciated I'd love to get this set up and running.

Re: GEC " Gecophone" BC2001 a little help please
 

You might want to start here

https://www.vintage-radio.net/forum/...d.php?t=141232

The member is still active :thumbsup:

Cheers

Mike T

Re: GEC " Gecophone" BC2001 a little help please
 

As the set is a HF Detector type something like PM1HF and PM1LF should be suitable with 2 volt LT supply or other low gm types of 4 pin triodes as the set was originally intended to be used with R or DER type valves.
I think that the instruction cards were supplied with the set for the owner to fit.
Some cabinets look to have never had the cards fitted as there are no pin holes in the doors so if the cabinet you are using hasn't had them fitted, it might be appropriate not to fit them.
I have one of these sets, a replica reaction unit is quite a project to make, you will need to be good and have the facilities for metalwork.
I can supply details of it and scans of the cards if required, PM me and I will see what I can do.
Mike.

Re: GEC " Gecophone" BC2001 a little help please
 

Should probably point out I have access a profesional workshop with just about every form of lathe and milling machine so if I can get the info on the reaction unktmit shouldn't be much bother. I did think the pm series valves might be ok but the originals of course we're 6v heaters.

Re: GEC " Gecophone" BC2001 a little help please
 

I had a set of plans for the reactance control, drawn by no a longer active BVWS member. After spending most of the morning searching my paper work I am unable to find them and running out of places to look.

John.

Re: GEC " Gecophone" BC2001 a little help please
 

According to the 1925 Brown Bros catalogue (BVWS Reprint) the set was being supplied by then with either 2 R5(V?) valves and 6 volt accumulator or 2 DER valves (nominally 1.8 volt filaments ) with 2 volt accumulator, it doesn't say whether the same value filament rheostat was used in both versions.
The set originally used 2 R valves with a 6 volt accumulator but as the R valve's filament was rated at 4 volts 0.7 amp the rheostat should be used to reduce the voltage to this, higher voltage would considerably reduce the valve's life.
2 volt filament 4 pin valves are the only ones that are now relatively easy to find, 4 and 6 volt types haven't been used much since the late 20's.
Mike.

Re: GEC " Gecophone" BC2001 a little help please
 

Out of interest any reason why American valves couldn't be used other than the bases something a bit more period looking

Re: GEC " Gecophone" BC2001 a little help please
 

Yes, they are American... Later DER valves look pretty similar to the PM series.

I have a similar issue with my Marconi 41 which came without either of the two plug-in coils. I have made some replacements and wound the primary which is relatively easy as I just needed to get the resonant frequency right, the secondaries (regen and 2nd valve grid drive) will have to be done by trial and error. You could do the same.

http://earlywireless.com/bc2001_picinfo.htm?LMCL=MWTN7W

Re: GEC " Gecophone" BC2001 a little help please
 

While looking for something else I came across the plans. If you still need a copy please Email me.

John.