A640 Chassis
Model: Murphy V1914
Year:1969
System:405/625 Line Hybrid
Valves:
2V1 PFL200 Video Amp and Sync Separator
2V2 PCL82 Sound Amp and Output
3V1 PCF80 Line Oscillator
3V2 PL504 Line Output
3V3 PY88 Efficiency Diode
3V4 DY802 EHT Rectifier
3V6 PCL85 Frame Oscillator and Output
Transistors:
1VT1 BF200 RF Amp
1VT2 BF115 VHF Mixer and UHF I.F. Amp
1VT3 BF115 Oscillator
2VT1 BF167 1st Common I.F.
2VT2 BF173 2nd Common I.F.
2VT3 BF173 Vision I.F.
2VT4 BF184 Phase Splitter
2VT5 BF185 1st Sound I.F.
2VT6 BF184 2nd Sound I.F.
CRT
To be listed
Condition:
Working not repaired or restored
Now, that IS nice and a good Lopt too ! 🙂
Nice set!
I’ve got an identical set to this, but guess what? Yes that’s right, the dreaded LOPT EHT overwind problem. The picture is blooming more and more these days so I’ve not powered it up for a while. I’m thinking of going down the tripler route. As I understand it I need to remove the overwind completely and connect the top cap of the line output valve to the input of the tripler and have 1pf cap going to ground too. Is this correct?
Correct about removing the over-wind and the Tripler placement to the TC of the Line-Output Valve. Although I’m not certain about the 1pF to ground. I did the Tripler trick on a 19″ RGD dual standard and didn’t use the cap, it worked fine without. Best check with the TV engineers on the forum to be sure or they may even answer here.
I had to use a tripler on my TV166 and sure enough chopped out the overwind completely and used a 120pF cap I think. It was many years ago though!
That bellcrank used to operate the system-change switches used to pop out of its pivot hole on mine which necessitated having to remove the back cover and replace it every time I switched from 625 to 405 or vice-versa. With hindsight I should have shoved a spindle of some sort into the centre hole to lock it into place.