Quote:
Originally Posted by Kevin Kuehn
Looking good. Do those jail bars move sideways when you adjust the horizontal hold? You could try adjusting the horizontal drive and see if that has any influence. The diagonal lines are just vertical retrace which is pretty common on that period set. There's a possibly you can add a vertical blanking circuit once you get all the other bugs out. Make any headway on voltage measurements, and locate the b+ going to the tuner?
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I have a quick question about the High Voltage Rectifier Tube.
I have 4 1B3GT HV Rectifier Tubes in my stash, the one that originally came with the TV when I got it that the only identifier marks on it are the words "VEE" stamped in red ink on the base of the tube and then the date code 9-53 stamped in red ink in the base, and then I have an RCA Branded 1B3GT Tube that's from the early 1950s, and then a Sylvania Branded 1B3GT Tube with a date code of 508 (50th week of 1948), and then a NOS IEC 1B3GT/1G3GT tube of which all of those tubes measure like brand new (the needle points squarely on 115 or so on each of them on the emissions test) on my Sencore Mighty Mite VII TC 162 Tube Tester and using the life test function on my tester the needle doesn't budge or barely budges which usually means that the tube is very good yet, and the grid leakage test measures around zero on all 4 of the tubes, but yet when I tried all 4 Tubes in my TV the tube marked "VEE" gives me the best picture out of all the tubes.
How is it possible for a tube to measure like brand new emissions wise and then perform like crap in circuit? Is it possible that my 1 Meg 1 Watt resistor in series with the picture tube anode cap could cause the High Voltage to perform like that?
And what I mean by the 1B3GT tubes performing like crap in circuit but measuring like NOS emissions wise is that when I use some of those tubes in circuit the picture cuts out when the brightness control is turned all the way up but then it comes back when its turned to the middle, but when the aforementioned tube marked "VEE" on it is in circuit the picture doesn't disappear when the brightness control is turned all the way up.
Any ideas about what could be causing that? Is it the 1 Meg 1 Watt resistor in series with the HV Anode Button for the Picture tube causing that?
Also I have not been able to get the B+ issue figured out on the Tuner yet, I tried the partially inserted tube method for measuring tube voltages like you suggested but I didn't have enough clearence under the tubes to insert my Multimeter probes.
Also the 6J6 tube has a shielded socket around it so it doesn't have any room at all for me to stick a test probe inside to get under the tube to take voltage measurements.
And no those Jailbars don't move with the horizontal hold adjustment, in fact when I adjust the horizontal hold knob I don't see any sort of difference in the horizontal adjustments.