Emerson 60's

[DaveWM]

looks like I may have an agc issue. 0v on the test point pin, if I put in -.7v the pic is much more stable, no tearing or sync issues. I was thinking I had an alignment problem all along, thinking agc is the key now...

[DaveWM]

looking good now will get some pics up soon.

I goofed up the alignment in a misguided attempt to "improved" the pic.

The real issue was a improper set of the AGC control. I was able to get the alignment back in order (see the tech section TV IF Alignment), adj the AGC and its looking very good now. I am letting it cook for a few hours to test it all out, but I think it will be a go.

[DaveWM]

here is a pic looks beter in real life. The alignment also made the channel 3 work as channel 3 and the fine tuning is much less critical.

[DaveWM]

AGC acted up again, pretty sure there is something thermal going on in there as it will eventully settle down, if I bypass the agc TP to ground with a .5 cap it works fine, right away. I will put a scope on the AGC and see what is going on, it reads -1.5 the whole time but I feel the 1.5 must have a bunch of garbage on it that is messing things up. I may just end up replacing all the parts in the AGC line to be sure. I did try a diff tube, no help.

[DaveWM]

Replaced a few more caps (they were the hard tube ceramic type, initally tested ok but what the heck) AGC work right now, looks very clean on the scope, picture is very good, on par with a direct video feed.

Anyone working on a vintage set, I HIGHLY recommend putting a scope on the AGC test point, esp if its a keyed AGC. A simple meter reading will not show the junk that maybe riding along (mine had the correct AGC voltage, but the AGC was the problem).

I am going to replace the damper tube as I have a slightly lighter screen on the left side.

[DaveWM]

more fiddling, I could not leave well enough alone, checked the IF curve and it was messed up, only one hump, turned out to be an intermittant connection on one of the IF transformers. re did the alignment for a broader band pass, less overall gain. The result is an excellant picture. Plus I "think" the vertical sync pulse is stronger (based on the size and what I remember it looking like).

This pictrue tube is by far the best of my B&W sets, excellant pictrue.

I was going to rebuild the vertical integrater for practice, using some copper clad pcb and discreet componets. I may still do that. Also the only other issue is the slighly jagged hammer on the vert sync pulse. Not sure about the relationship of the vert sync pulse and the effect its haveing on the horz sync just on the hammer. I am wondering if somehow the hipass filter of the horz sync is some how getting a bit of the vert sync low pass in.

[DaveWM]

here is a screen shot, looks better in person, the glare is not there on the face of Ward

[DaveWM]

decided to leave the vert intergrater alone for now, I have lots of other projects that need the attention.

I wiped some restrore a finish on the bunged up legs, made them look a lot better. The set has a very glossy finish (sorta like a grundig) with some scratches in it, and some minor scrapes on the edges. I am going to try some rubbing compound on it. The plastic bezel around the crt is plastic painted gold. Not perfect but ok. The feet could take a coat of brass colored paint as they were pretty rusty. Other than those cosmetic issues this is prob my best B&W set as far as the picture goes. I like the legs, sets it up a bit higer for viewing. I think I can find a home for it in the office next to my grundig console, same style (the legs) should look nice. I plan to use it as a daily driver for my vintage watching at lunch time.

Next up a few quick looks at the Sylvania SS color. If I can find a quick fix great. If not I will jump back to the smalle maggie am/fm/phono/tv console and see if I can get that interlace worked out. I am pretty sure its going to be in the vert integrated.

[Sandy G]

GREAT job !! Aren't you glad you got it now ?!?

[DaveWM]

yepper, turned out to be a good one!

[DaveWM]

Update:

its is developing a vert sync lock issue. the vert hold is critical, will drift as it warms up.

I tried subbing the sync sep tube, no joy. The video signal is strong, horz lock no problem. The blanking bar looks good, the hammer is slightly jagged (the start and stop points are offset so it not a nice perfect rectangle, but its been like that for a long time, before the issue).

I suspect its the vert integrater since the vert osc seems to have plenty of adjusment both way, just a very soft lock.

I will get the scope out 1st and check the vert sync pulse to see how it looks before and after the integrater. The plan is to check the pulse before the integrater, then pull the vert out tube (brightness all the way down) and check the grid of the vert mult tube and see how it looks.

I hope this is a push over since I really like watching this set and don't want a dog.

[DaveWM]

well I just have not seen enough sync pulse traces to conclusively say it looks weak, but it looks weak. And this is at the video detector, so its before the sync separater.

I think this may tie into the jagged hammer as well. I am going to try using a detector prob and see if I can trace the composite signal back.

What bothers me is the pic is VERY good. I am wondering if my vert sync could some how be getting clipped.

prob try clamping the AGC again..

[Reece]

Dave, look at it this way: this hobby keeps you out from underfoot, and keeps you home where tabs can be kept on you, and you're not out running around somewhere doing who knows what. You need to play up this angle.

[DaveWM]

LOL

[DaveWM]

I am going to try ANOTHER sync tube, but I will make sure it test good even if its NOS.

I checked all the voltage/resistance, one was off on the AGC side of the sync tube was 70v not 40v but since it was on the AGC side I discounted that as part of issue.

It was working fine and has slowly been getting worse. not it will barely lock at all. Horz is rock solid.