1971 Philco color Tube Hybrid

[zeno]

Keep in m ind for arcing EVERYTHING is at 25 KV above ground.
Tube, socket, filament winding, HV lead & any small parts at the socket.
So they can arc anywheres.

[Lain94]

Originally Posted by zeno

Keep in m ind for arcing EVERYTHING is at 25 KV above ground.
Tube, socket, filament winding, HV lead & any small parts at the socket.
So they can arc anywheres.

Yeah which is pretty annoying lol. I also noticed that the old HV rect. tube socket has loose pins/posts on it which makes me wonder about connection issues. Anyways I am replacing that too soon to rule it out.

Photos of the new old stock flyback installed! It looks much beefier and more insulated than the original. Also noticed that it uses what looks like asbestos fabric to insulate the three wire winding that leaves to go up to the tube socket instead of the rubber the old one used.

I extended the old short wires with new wire so I had plenty of slack to work with. I finished up by adding extra insulation via heat shrink tubing. Installed a 1N5408 silicon diode rated at 3 amps and 1000Volts just because I wanted to for peace of mind.

How do you test a Focus divider btw? I have not tested it yet.

https://imgur.com/a/4rVeii9

[Lain94]

One more question: In regards to the three winding wire loop under the rubber tire of the flyback transformer; does it have polarity and if so how do I know which is which in regards where to where each one for each of the two posts of the HV rect. tube socket the old one was at? The schematic does not show any polarity for the two wire leaving the three wire winding so I am assuming it does not matter which of the two posts they go to as long as each goes to the ones that the old flyback went to.

[Lain94]

I circled the part of the schematic where that winding is at. I see no indicators differentiating either end of the winding.

https://imgur.com/a/CDJ7p21

[mrjukebox160]

No polarity on that.

[Lain94]

Thanks, I just wanted to be sure before I turned it on again. Now the arcing problem suddenly went away after putting in the new HV cup socket and flyback transformer. The new problem is the 6CG3 damper tube started rapidly redplating within just 10-20 seconds of me turning the tv on to test it and I then quickly turned the tv off as soon as I saw this.

No other tubes were showing red-plating or any other signs of trouble. No other symptoms present, I heard the high pitched frequency which sounded normal as all the tube filaments including the CRT glowed. I am pretty sure the horizontal drive is working and just am unsure what is causing there to be so much current suddenly going through the damper now.

I read online that sometimes the yoke can be shorted and cause it. I already replaced all the electrolytics and was careful to make sure they were put in correctly so I highly doubt that was the issue.

[zeno]

Test for dividers is inspection for cracks, bulges, heat etc.
Beyond that the focus voltage needs 6KV +- from it. Third wire is
ground or nearly so.

Zeno

[Electronic M]

If it started red plating as soon as you replaced the flyback, then the flyback replacement caused it...the more wires you swap at once the more likely a screw up is, also once in a while part subs aren't as functional in circuit as Sam's thinks.

[Lain94]

I looked over all the connections and sure enough one of the wire going to the flyback from the chassis was on post X when it should have been on post 9. I am not entirely surprised that I made the mistake though since I was probably tired when I was working on it. All the other wires though are as they should be. I did another inspection of the whole chassis to look for any other potential issues. I noticed the socket where the thermistor and degaussing coil plug into the chassis is VERY loose and questionable. The pins were basically floating up and down and had way too much give making a possible connection issue where one or two of the four pins may not have been making good contact if any at all.

I was not always turning the tv on with the degausser plugged in (usually not) The last time I know I didn't because I did not want the degausser to be a potential issue at this time. Aside from that I saw no apparent connection issues, but I find it concerning how Ford Philco had sloppily wound wires onto posts and how easily bent many posts also were. It is not a surprise to me that this tv has numerous electrical problem despite being low hours for its age.

I corrected the wiring mistake I made on the flyback and will be conducting another test soon to observe cautiously for any other signs of trouble. Any recommendations on where to set horizontal bias control or any of the other controls for initial setup? Service mode vs normal? ect. I have a HV probe to check HV but a bit nervous about doing it and getting zapped. Can I use the oldschool RCA HV probe I have with a standard multimeter safely?

[Lain94]

Good/Better news: Circuit breaker had tripped for the low voltage circuit protection I realized when I tried turning the tv on again, which mean the breaker did its job correctly! I reset it and after testing the tv again I for the first time ever was able to get as as far as seeing ANYTHING on the screen including vertical deflection with no trouble. Solid state audio circuit still working fine as well. However a few moments after vertical deflection was achieved the CRT seemed VERY bright almost like HV was way too high, and elecricity was going all over the inside of the CRT and (possibly outside and arcing over to one of the terminals of the focus divider before a surge of electricity or current made it way from the flyback to the 6KD6 horizonal output tube tip which was very visible and a bright brief glow happened before going back to looking normal. Nonetheless I quickly turned the tv off as soon as I heard the audible arcing. I was stunned at how bright the CRT was, I knew it was good on emissions and lowish hour but that was the brightest CRT in a hybrid or full tube set I have encountered so far.

My possible suspects of this issue are: The HV anode was somehow not on firmly enough, carbon tracing around the HV anode due to dirt or dust? Bad Focus divider? Yoke seems to be ok. I did not smell or see anything that was suggesting any shorts. I did not screw in the chasses to the wooden cabinet as I had grown tired of doing that only to have to take it out over and over so the focus divider may have been too close to the CRT aquadag and encourage an arc that way?

While I am not out of the woods yet with this tv's troubles, I am able to run the tv to the point now where I get visible static on the tv, sounds of static, a raster line and then vertical deflection! A good morale boost for me considering how much I have had to fight this tv.

Pics of this issue and situation: https://imgur.com/a/2ccF0ux

[Electronic M]

A few things. Did you connect the CRT day grounding to the chassis? In most sets there's either cabinet provisions to do that whe the chassis is bolted in or a separate wire....If the chassis is out and you don't run your own wire the CRT day ground can arc to the chassis and or yoke.

If your HV isn't too high (measure it to confirm) it could be your screens (G2) are too high...I've seen those set ridiculously high by previous owner morons before.

[Lain94]

Issue resolved, It appears the aquadag of the CRT was not making good contact with chasiss which is ground. Also set horizontal bias to roughly mid position. TV is now working with no apparent arcing, sound is solid state on this tv and functions as it should, tuning also seems ok although I kind of dislike AFT this tv has, there is a way to disable it which I may end up doing.

There seems to be some sort of issue with the color not syncing up, is it almost like it is out of phase. Barber poll pattern of colors. Also need to adjust vertical linearity and horizontal size a bit.

I had the tv on for an hour when I was testing it and seeing what controls were responsive. Tint and color killer all seem to do little to nothing. Color intensity works but only makes the barber poll pattern of colors become more intense.

https://imgur.com/a/KUJj5Fy

[Electronic M]

If the chroma osc is not in sync and the set is barber-poling then tint won't do anything noticable.

Color killer is basically a unimportant nicety....It suppresses color in snow when no signal is applied. It used to mute color on monochrome shows improving the viewing experience by sensing the absence of color burst, but since the 80s or 90s virtually all TV stations and signal sources run the color burst constantly even if the show is monochrome...So in essence unless the color killer is preventing a color show from displaying color it's the appendix circuit of the TV.

There should be a color osc/AFC adjustment procedure in Sam's...Follow it and your tint should work and good color should be achievable.

[Lain94]

Update: I am still having the same issue with the color being out of sync and causing a barber poll pattern. I measured the base of Q95 Burst Amp Transistor in circuit with an oscilloscope. Should be 7V along with a certain waveform pattern but is measuring way higher like closer to 45v or so and the waveform also dose not match up. I am beginning to wonder if the transistor is leaky or some other transistor or IC is causing issues.

https://imgur.com/a/3nX50qh

[old_tv_nut]

Posting a schematic would help. Since you changed the flyback, there's a possibility you have a wrong/bad connection for a burst gate pulse from the flyback causing your lack of color sync.