20-04-2021, 08:45 PM
Ed_Dinning Wrote:Hi Folks, I have a version of this set, it has Ct bases fitted but all 4 are fitted with what looks like factory made adapters to octal bases that are fitted with DK series valves
Ed
Hi Dr Ed.
I'd be interested to know if the adapter bases convert the octal pin outs to the CT8 orders of connection? For example CT8 pin 2 and 3 are filament, on octal its 7 and 2. There are also other differences.
Or are the CT8 bases wired to suit the octal pin out order?
I expect the octals you have in your set are the American GT "short" valves, as in my 5214, I have some spares, plus some post war Mullard octals that are electrically compatible but if seated in adapters wouldn't allow the back to be in place as they are too long for the extra height of the bases.
This set is a little confusing as it has a date stamped electrolytic, chassis, and speaker, all 1943, but has the earlier oscillator coil in can above chassis, and, the tuning dial is marked with pre war station positions and is medium/long wave being after the Droitwich transmitter was shut down.
There is a bit of a setback regarding the restoration, in that checking the valves out fitted to the set, the DK1 has an OC filament, the DF1 and DAC1 have no emission, and the DL2 is very low.... Of course I haven't any of those or a replacement speaker that's needed, so the searching will start soon.
On the bright side the output transformer does seem in good order electrically.
Amie.
