It's really starting to take shape Bob, and all without really doing any recapping or resistor checking. Fantastic information. What a great series for a beginner like myself.
Thanks but that's not quite true. The audio amp, vertical oscillator, vertical integrator and part of the horizontal have been recapped. The RF and IF is all mica and ceramic and are probably fine. The main thing left is the sync, AGC and video amp.
Here in Tasmania we got TV in 1956 and damper diodes with heavily insulated cathodes had been developed by then, viz 6AX4 and 6AU4 with octal bases and the Nuvecar 6AL3 with a cathode cap. Obviously earlier sets made use with ehat they had, but for me it is dtill wierd to see a 5V4 used as a damper in a TV line output stage…love how the directly heated cathode, of course has its own isolated heater overwind in the power transformer. The line output transformer looks strange and naieve too. The 6BG6 is a really beautiful looking line output valve…looks like an 807 with an octal base, so much nicer looking than the later, uglier 6BQ6’s and 6CM5’s! I suppose that heater winding in the power transformer for the 5V4 is possible becsuse this EHT is so low, could not imagine this with later, higher voltage EHTs peoducing 15Kv at the tube anode and with 6us long, 4Kv high pulses st the damper cathode which would certainly flash over ipbetween the power transformer windings…always learn new and interesting things from the earlier, more naiebpve designs!
True and even when 6W4s came out a short time later there were still some models that used a separate filament transformer for them with heavy insulation on the leads.
Just looked up thet datasheet for the 6W4, only 125mA continuous, 3.85Kv PIV and 3.5w Anode dissipation, but the supurlative is the cathode-to-heater insulation which is 2.3Kv heater negative with respect to cathode. The 6AL3 which was in 95% of Australian 110 degree B&W TV’s in the ‘60’s despite being in a smaller bulb with a nine pin Nuvecar base is 220mA continuous, 7.5Kv PIV and 5w anode dissipation….the cathode to heater is a whopping 6.6Kv with unspecified polarity. I pulled a 6AL3 to bits decades ago, the 1.5A, 6.3v heater was a bunch of tungsten wire that went up and back about three to four times, this had a standard coating od zirconium orthosilicate over it, much the same as you ‘d see in modt other indirectly heated valves, but then around this was a helix of kovar wire with a THICK coating of zirconium dioxide slurray anf then, finally all this was stuffed down inside the cathode cylinder which was a good 1/8th inch in diameter. At the time I wondered why until I realized that it is the CATHODE of the damper that connects to the EHT primary and has huge back EMF spikes every 64us at flyback. The 6CJ6 is another valve that is rarely ever seen, it has the same sixzed bulb as a 6AL3 but is a horizontal output beam tetrode, I have one in an old 50’s Marconi Mk-IV B&W broadcast montor…a beast of a thing with a 90 degree tube, waveform monitor underneath and a 6BK4 EHT shunt regulator to stop the picture “blooming” during dark scenes! Tell me, do you ever come across the 6CM5/EL360 horizontal output beam tetrode over there….they were about 75% of all horizontal output valves over here.? When we got colour, (PAL-D, 50Hz V, 15.625KHz H, chroma 4.43361975MHz) in 1975, B&W sets went to the tips in droves and I hoarded the valves! None of our colour sets used valves, all were semiconductor. The most common was the Philips K-9 chassis.
@@eDoc2020 Yes, but the heater is connected to the cathode internally. The Admiral has a dedicated, well insulated filament winding just for that tube. damper tube like a 6W4 has a separate cathode and heater with a high breakdown voltage.
Nice to see the hickok 600a out again. Please do more vids with testing tubes during restoration. Glad I bought my hickok 752 and Emc tube testers when I did there way more on ebay now then there worth. Would like to exchange the EMC for a Hickok 800a or 600a
Hi. Yes, we know each other and chat behind the scenes. No, I have not. The way these sets are built and wired it's hard to get bit unless you do something really foolish.
also mine does not have that tall resistor with multiple taps........has a shorter one and its not totally rearward but in front of the flyback near edge of chassis
my crt 20b1 chassis has some kind of rubber maybe around the neck where the tube narrows down to neck size. Yours doesnt seem to have this rubber on it.
@@bandersentv the rubber tube insulating cone it is ahead of the yoke, the tube where the glass rapidly goes cone shaped there is a rubber support ring with squares cut out in this rubber cone.
Now Tube testers i envy you for, as they go for £250-£300 minimum here in the UK and that's the basic models, not the hickock's or AVO's or TV-7's so i chose to get a Curve tracer - uTracer 6.2 from Ronald at his dos4ever website, testing my radio tubes first then I've got a mountain of TV tubes to test
Please continue with your theory of operation lessons as you go through. I'm really enjoying the series. Thanks
Bob great learning video and great progress and a nice step by step procedure great learning video thanks Mike
It's really starting to take shape Bob, and all without really doing any recapping or resistor checking. Fantastic information. What a great series for a beginner like myself.
Thanks but that's not quite true. The audio amp, vertical oscillator, vertical integrator and part of the horizontal have been recapped. The RF and IF is all mica and ceramic and are probably fine. The main thing left is the sync, AGC and video amp.
Amazing results
Here in Tasmania we got TV in 1956 and damper diodes with heavily insulated cathodes had been developed by then, viz 6AX4 and 6AU4 with octal bases and the Nuvecar 6AL3 with a cathode cap. Obviously earlier sets made use with ehat they had, but for me it is dtill wierd to see a 5V4 used as a damper in a TV line output stage…love how the directly heated cathode, of course has its own isolated heater overwind in the power transformer. The line output transformer looks strange and naieve too. The 6BG6 is a really beautiful looking line output valve…looks like an 807 with an octal base, so much nicer looking than the later, uglier 6BQ6’s and 6CM5’s!
I suppose that heater winding in the power transformer for the 5V4 is possible becsuse this EHT is so low, could not imagine this with later, higher voltage EHTs peoducing 15Kv at the tube anode and with 6us long, 4Kv high pulses st the damper cathode which would certainly flash over ipbetween the power transformer windings…always learn new and interesting things from the earlier, more naiebpve designs!
True and even when 6W4s came out a short time later there were still some models that used a separate filament transformer for them with heavy insulation on the leads.
Just looked up thet datasheet for the 6W4, only 125mA continuous, 3.85Kv PIV and 3.5w Anode dissipation, but the supurlative is the cathode-to-heater insulation which is 2.3Kv heater negative with respect to cathode. The 6AL3 which was in 95% of Australian 110 degree B&W TV’s in the ‘60’s despite being in a smaller bulb with a nine pin Nuvecar base is 220mA continuous, 7.5Kv PIV and 5w anode dissipation….the cathode to heater is a whopping 6.6Kv with unspecified polarity. I pulled a 6AL3 to bits decades ago, the 1.5A, 6.3v heater was a bunch of tungsten wire that went up and back about three to four times, this had a standard coating od zirconium orthosilicate over it, much the same as you ‘d see in modt other indirectly heated valves, but then around this was a helix of kovar wire with a THICK coating of zirconium dioxide slurray anf then, finally all this was stuffed down inside the cathode cylinder which was a good 1/8th inch in diameter. At the time I wondered why until I realized that it is the CATHODE of the damper that connects to the EHT primary and has huge back EMF spikes every 64us at flyback. The 6CJ6 is another valve that is rarely ever seen, it has the same sixzed bulb as a 6AL3 but is a horizontal output beam tetrode, I have one in an old 50’s Marconi Mk-IV B&W broadcast montor…a beast of a thing with a 90 degree tube, waveform monitor underneath and a 6BK4 EHT shunt regulator to stop the picture “blooming” during dark scenes!
Tell me, do you ever come across the 6CM5/EL360 horizontal output beam tetrode over there….they were about 75% of all horizontal output valves over here.?
When we got colour, (PAL-D, 50Hz V, 15.625KHz H, chroma 4.43361975MHz) in 1975, B&W sets went to the tips in droves and I hoarded the valves! None of our colour sets used valves, all were semiconductor. The most common was the Philips K-9 chassis.
Despite the pinout the 5v4 is actually an indirectly heated cathode tube.
@@eDoc2020 Yes, but the heater is connected to the cathode internally. The Admiral has a dedicated, well insulated filament winding just for that tube. damper tube like a 6W4 has a separate cathode and heater with a high breakdown voltage.
Nice to see the hickok 600a out again. Please do more vids with testing tubes during restoration. Glad I bought my hickok 752 and Emc tube testers when I did there way more on ebay now then there worth. Would like to exchange the EMC for a Hickok 800a or 600a
Since that stack of power resistors is open on one end, is there some way it could be replaced with a rheostat? Just musing.
It's not a stack - it just has taps. Sure you could but you would have to modify the chassis to mount it. I hate doing that.
Arking, and Corona, and whatnot. 😂
at 15:59 the picture just stops jumping or jitter jiggle all together did you adjust something to make it stop?
Not to my knowledge
Shango Dan mentioned you in his recent video Have you ever been shocked by the output of the flyback transformer?
Hi. Yes, we know each other and chat behind the scenes. No, I have not. The way these sets are built and wired it's hard to get bit unless you do something really foolish.
my width is too wide and I dont know what you tweaked to get the image immediately centered!
Watch part 188. Are you sure you have too much width? Does your set have a "double-d" mask? If so, the image should slightly extend off both sides.
also mine does not have that tall resistor with multiple taps........has a shorter one and its not totally rearward but in front of the flyback near edge of chassis
Right. This is an earlier 30A1 chassis.
my crt 20b1 chassis has some kind of rubber maybe around the neck where the tube narrows down to neck size. Yours doesnt seem to have this rubber on it.
Not sure what you mean. Under the focus coil?
@@bandersentv the rubber tube insulating cone it is ahead of the yoke, the tube where the glass rapidly goes cone shaped there is a rubber support ring with squares cut out in this rubber cone.
Now Tube testers i envy you for, as they go for £250-£300 minimum here in the UK and that's the basic models, not the hickock's or AVO's or TV-7's so i chose to get a Curve tracer - uTracer 6.2 from Ronald at his dos4ever website, testing my radio tubes first then I've got a mountain of TV tubes to test