Now that I've got the yoke assembly all fixed up the next step was to correctly wire up the radar CRT socket with the wires from the circuit going to the correct pins of the tube. So I looked at the data of the VCR140 radar tube and the schematic of the TV and worked it out from there. I learned with the connections the main difference between the VCR140 radar tube and the 12LP4/12JP4 TV tubes is that the TV tubes have 2 grids and the radar tube only has one. Also learned too that the VCR140 needs an anode voltage of 5KV whereas the 12LP4/12JP4s need 12KV so I wonder if the EHT has been modified to output 5KV instead of 12KV? I followed the grid connection back and it didn't seem to connect to anything, this set has probably been continuously tinkered with when it was used in television training, so I connected the grid lead to the grid output connection closest to the right voltage out of the two grids. Anyhow after doing all this I felt the set was ready to be rigged up and fired up, so I connected parts together to the chassis, the CRT, the EHT and the speaker and then plugged the set to my variac and wound the voltage up gradually. The valves lit up, the radar CRT filaments lit up which is excellent, nothing went boom which is excellent, but nothing came up on display. I soon realised the heaters in the valves in the EHT were not lighting up. On checking the heater connection to the RF valve in the EHT, it was not at all connected to anything so I connected it to the 6.3VAC output of one of the mains transformers close to it to give it heater current, and on power up it lit up. So powering up the set again the RF valve lights up, but the rectifier valve doesn't and no raster appears on the radar tube, so either that rectifier valve in the EHT is faulty or there's a fault in the EHT circuit somewhere. Anyhow I'm glad I've made it to this stage of restoration of the TV to the point of switching it on and am glad nothing went kaboom, I will continue on working on this TV when I know what to do next. I will have to check those canned valves too to see if the heaters are lighting up as I neglected to check them initially. Anyhow below is a video followed by pictures of the TV being assembled and switched on:
Powering up the TV for the first time, as seen the set powered up okay, the visible valves lit up and the radar tube filaments are lit up, but nothing appears on the tube
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Radar tube socket plug wired up ready to be connected
EHT RF valve heater wires not connected to anything as seen
EHT RF valve heater wires now connected to mains transformer 6.3VAC valve heater supply winding
TV all rigged up and ready for power
TV powered up for the first time, all visible valves are lit as well as the filaments on the radar tube :)
Radar tube filaments lit up as seen
Well that's where I'm up to to date with the restoration work on this TV set, stay tuned for further updates when I next tinker with this set!!!