Those switching power supplies run at or higher frequencies than TV set horizontal circuits (15734HZ). So those diodes would be an excellent choice.

back in, no HV, HOT starts to red plate. Hmm horz osc filament not on. move tube around and it comes back, HV comes back, wiggle it again, HV goes out. So it looks like the filament connection to the 6FQ7 is intermittant (prob what side lined it in the 1st place). I tried a different tube just to be sure it was not the tube itself, same deal. So I will pull the chassis and do a close up exam, my guess is a ground stake (if there is one that just feeds this tube) or maybe a loose contact pin socket. What ever it is I dont think it will be too much. Plus I have some NOS sockets that I would be willing to just replace it, esp on such an important tube. I have had tube socket failure before on this type, last time was the vert osc of a predicta. the bridge between the tube PCB pin and the actual socket can fracture, very hard to see, and the only real way to catch it is with a socket test adapter, since touching the pin sockets with a test lead will often close the cap and make it look good. I prob just got lucky the 1st time after checking the tube, and the install happened to be good (when the set was working after the inital check out). I do recal the HV was not there when I got it and I did a wiggle of the tube and it came back. Its just a bit too sensitive as is.

good vert/horz sync, good color, just some intermittant snow so prob a dirty tuner, but looking good. I will take a close look at the 6FQ7 socket next time I have it on the bench.

reflowed the 4/5 pins on that socket they looked a little cold. I also reflowed the ground stakes. Working ok, but will wait until tonight for darkness and see if I can wiggle it OFF now. I used my pick to also tighten up the sockets.

while I have good light out in the garage I plan to pull the tuner case off (I found one that fit) and clean the tuner contacts. the pots have been cleaned and lubed but for the pots on the back, I am going to leave them be for now since I dont think they get much use anyway.

Still have to find a place to mount the cathode fuse for fusing and checking the HOT.

Then once you got it all fixed up you can stand it up on end in the garage and forget all about it. Just like me.... The fixation is the escape into the diagnostic realm and the sense of accomplishment when the thing actually works. Its hard to get that when you work in a cubicle or make sandwiches for an existing.

Its to bad we cant do this for a living. The timing is a few years off, thats ok though. I would much rather get cancer from a cell phone than a stupid ass pipe.

well I have a B&W maggie astrosonic combo, so maybe I can just set this one next to it, then use depending on whats playing.

I still have a lot to do after the TV, The TT needs to be gone over, mostly just clean out the old grease, and replace. Will need a new needle for sure, I just hope the cart is ok. Then all the little caps in the stereo tuner/amp which tend to dry out. When thats all done I will see if some restore o finish will be enough for the wood work.

going to check the B+ delay to see how that is working, will post afterward.

ah ha, the relay has to do with instant on (switchable).

interesting, instant on take about 15 sec, with out it about 30, so not exactly instant. I can see all the filament barely glowing in the dark.

I'm all for disabling the instant on feature. As we all know, that really helped to kill alot of tube TV's. Congratulations, Dave, on aquiring this fine set.

Fortunitly there is a switch that disable is. I was thown by the relay in the B+, its kept off during instant on mode.

I still have a bunch of work to do, but this is prob the best cabinet I have had to start with.

Huge thanks to MikeH for the HV cover, its in perfect shape, arrived safely today.

time for an update,

its looking good, the astrosonic needs service, and I have a line pairing issue with the vertical, not bad but not right. You can adj it out with the vert hold, but I still need to look into that.

My plan is to pull the vert osc tube out (brightness down) and scope the grid signal going to the vert out and look for horz noise.

It has most of the orig caps in the feed back loop, so I can check along there as well.

I was thinking of checking the boost supply to see how it looks on the scope, I dont know this but was just thinking if the boost filter cap was weak, maybe the boost voltage would have too much horz hash on it, getting into the plate circuit of the vert osc. there are a few other decoupling caps around there as well.

I dont know how much is too much so I will prob end up having to check a set that does not have the pairing issue at all.

On an old B&W I had this problem but much worse, turned out to be a bad yoke that was leaking horz back thru the vert windings and back into the vert out transformer. that was a tough dog (for me anyway).

Back in the day when I was servicing TVs fairly often a poor interlace problem could be fixed simply by reducing the signal vertical pulse to the sync servo. It reduced lockin range but interlace would be good to perfect throughout the range. In other words too strong a vert pulse would cause doubling.

Could the interlace issue just be a limitation of the circuit? Years ago, Consumer Reports magazine used to test for interlace quality among other things. One of their comments for some sets was "you can improve the interlace by careful adjustment of the vertical hold control". I remember having several TVs that worked that way, maybe all black-and-white sets. My brother bought a new Sony KV-1920D color TV in 1977, and I remember it was the first set I had seen where the interlace remained the same (almost perfect in that set) regardless of the vertical hold control's position within the in-sync range.

perphaps, but I know that there is variation between sets that are near clones. Its not a huge deal, but I will persue checking it out with a scope. I often find the best way is to compare to a set that does NOT have the issue (and is the same or very close in circuit). This shows up differences on the scope better than some of the iffy pics of a scope trace on sams. Mainly I want to zero in on the output form the intergrater and the B+ to look for horz noise.

Next time I fire up my CTC-16 combo, I will have to adjust its vertical hold and see how its interlace is affected, if at all, and how good it is in any case.

got a pretty strong single ghost about 3/4" offset on the right. Turning the color down and its still there so I assume its in the Y channel. going to try a new video amp tube just to see if it has any effect. Maybe a faulty delay line?

its such a big cabinet I dont really want to move it and pull the chassis.

I guess I could try injecting a signal starting at the output from the video amp and start working back, but maybe easier to just put up a test pattern and see if I can see the ring, if so then work back.

Its not really a ring, as its only one ghost, more like a reflected signal. Maybe a tuner issue?

Do you have a telephone sitting on top of the set?

Do you have a photo you can share of the screen?

here it is

Looks like IF ghosting, my CTC-4 does the same thing just not as noticeable.

very common issue with our older sets.you could tweak the coils but i really wouldnt mess with them too much.can you lessen them with fine tuning?when cable came into vogue in the late 70s,i had to tweak many of these to clear the picture up.many hours twisting and turning.

I dont think I could tune it out, not sure but I think I tried that. the fine tuning is very touchy, not sure if its a stripped gear or something else, I never cared for the fine tuning knob inside the channel select knob used on maggies. I will go back in and double check to make sure I have all the tube shields in place. other than this one issue it has one of the best pics of my roundies. It also does NOT have the line pairing issue I am fighting on the sylvania. the deflection boards are idenical as far as the circuit, but for a 80uf (sylvaniia) vs a 50uf( maggie) cathode bypass cap AND a .002 disc cap that bypasses the vert hold control (on the maggie, not on the sylvania). other than that they are the same. The sync pulse output has a different resistor value (39k maggie, 220k sylvania) to ground. Perhaps attenuating the sync pulse more in the maggie. the both have VDR's on the plate return circuit of the multivibrator, I have a replacement on the way for the sylvania on the outside chance that somehow that is causing my pairing issues. I hope to get the sylvania in the same room as the maggie and do some side by side comparisons. I may do the .002 bypass on the vert hold just to see if it makes any difference. I just checked the ctc-16 also has a .0022 cap bypassing the vert hold pot...

tried the fine tuning, you have to de tune so far out to lose the ghost that all color is gone and fine detail it gone as well.

here are some more screen shots, its not too noticiable

I'd call it good, personally.

I tried a new 3rd IF no change. it does not have a shield over the 3 IF, and the tube socket did not seem to have a ground contract, so I assume that is correct. Put one on it anyway, no change. I did not try 1st or 2nd IF tubes yet. Will give that a try, if that does not do it I will just call it ok for now. Oh also tried the video amp (6GH8) with a couple others inclding a 6EA8, it has a shield which was in place, again no change.

A ghost that is that clearly defined, it seems to me, must be delay line related. Rather than the line itself, I would check the resistors and any fixed coils associated with the delay line, especially on the output end.

Edit - also check grounds in the video section

roger that, will check out around the output of the delay line.

there is a 1800 ohm 5% right after the delay line (back thru a coil then the plate circuit B+ of the 2nd video amp. there is also a 2200ohm resistor across a peaking coil after the coupling cap from the delay line that goes to the grid of the video out, will check that one as well (prob did not check before since it was in P with the coil so will have to take out of circuit to check, same with the 1800 ohm (will have to take out of circuit, will prob just replace both).

Question, do those need to be carbon comp resistors? or will metal film be ok?

(the post delay line and the one across the peaking coil).

Metal film will do just fine

Have you tried tweaking the mixer plate coil in the tuner? Sometimes an eighth of a turn either way will make a major improvement in the IF response curve (operative word is 'sometimes').
oc

I will flag the alignment tool and give that a try if the before mentioned delay line parts make no change.

I have a 1076 that I could also use by injecting at the video out and work back, just have not bothered to get it out.

Dave, I had assumed that you were injecting video.

Two simple checks that you might do prior to twisting coils:

Back in the pre-Cable era, before grounded feed lines, the tuner balun coils often failed. You might verify the continuity of them. An open antenna-side coil will often work quite well, but it may produce a ghost.

Also, I presume that this set has an FM radio. Many console FM radios offered the option of an internal antenna for local reception, plus a jumper to connect to the VHF TV antenna for fringe reception. I've seen set owners forget to disable the internal FM antenna when using an external antenna and this can also create a single negative picture ghost.

Jas.

ant not connected, using a 300/75 matching transformer to connect from cable from converter box to set. I will check the balun next time I pull it out for the other stuff.

well the 1800 5% resistor of the back of the delay line had indeed drifted, was 2200, I had high hopes, replace it, still there, maybe a bit better but hard to say, prob me just wanting to thing it did something. there is a peaking coil after the delay line, but its got built in resistor so I cant test the resistor (one of those sqaure types with the resistor on the top, covered up.

The only thing I can think to do next is to get a good hard patter, like vert bars from the pattern generator, and see if I can see the ghost on the scope, then signal trace to see if I can find where it comes in.

while I had it out I decided to check the horz current, was only 175ma and that was at full line voltage. There was a top for 120vac and 128vac on an exposed term strip, for fun I tried 128vac, could not get the full raster, so put it back. 175ma is plenty good anyway. Maybe my HOT is getting weak.

and a new problem the vert has intermittant shakes (pic will be fine then just dims slightly and gets shaky) tapped around could not find any tubes. I was even thinking maybe the HV (boost voltage used for the vert). reseated the vert tube nothing. I am thinking of HV only because of the funny dimming that takes place when its shaking. will put the hv meter on it and see. the spells last a few seconds then stop for a short time then a few seconds...

did not clear up after warming up for 30min. this is new...

Sorry the resistor didn't cure the ghost.

Dimming and vertical shaking -- could it be AGC instead of HV?

no this is somethingn very odd going on, I just timed it, every 20 seconds I get a vert shake that last about 3 seconds, its like clockwork.

I have had odd bends (hulas I call them) that seem to be a beat freq of the vert rate vs the line rate, slow moving weaves.

argh...

when I had the hula it was a bad ground on the defection board of a mid 60's B&W maggie.

yep still doing it, every 20 seconds it gets the shakes for about 3 seconds.

Yes, this sounds like 60 cycle hum getting in somewhere and rolling through due to the 59.94 Hz vertical of NTSC. Need to check grounds, but also power supply hum.

this is getting strange, I scope the 405v B+ get the normal amount of ripple then bang 3 seconds of wild fluctions. take out the 3rd IF (no sync) same deal. then I scope the power line (thru an isolation transformer), sure enough garbage on the line now time to go try another set in another room, yep, same deal (this is another CTC-16) ok looks like something somewhere is messing with my power line. I am near a few real hogs (universal studios).

I think I will stop now and try again tomorrow.

I plugged in my line meter, yup, like clock work, I even notice my shop light dimming. I checked to see if there was a piece of equipment (pool pump, AC compressor) that maybe was thermal cycling, but all seems ok. going to try a few differnt outlets. not seeing anything on the modern sets, but I would assume they have better power regulation.