Hallicrafters T-67 HV corona ring

[dcl0]

I've checked the wiring against SAMS and only have the thing configured for T-67. I can't see a part number on the yoke, but it looks like the one pictured in SAMS. The number on the flyback is 55H11S which is different than the one specified in SAMS (55C113)! Hmmm, would continuous use of this flyback damage anything?

[Kevin Kuehn]

Originally Posted by dcl0

I've checked the wiring against SAMS and only have the thing configured for T-67. I can't see a part number on the yoke, but it looks like the one pictured in SAMS. The number on the flyback is 55H11S which is different than the one specified in SAMS (55C113)! Hmmm, would continuous use of this flyback damage anything?

I looked up both flyback numbers in my Thordarson cross reference and while 55C113 crosses to a Fly 1, there is no listing for a 55H11S? Does your flyback even resemble the one pictured in Phil's restoration pictures? I'm a little suspicious that that number could be a much later part, possibly not a direct replacement. On the other hand if it looks like a typical Fly 1 it probably an OK sub. My newest cross reference no longer included Hallicrafters so I have no way to verify when a 55H11S may have come into existence.

[dcl0]

Whoops! I made a mistake-what I get for just looking through the grill. Its actually 55H113!



Here is the best photo I can get of the yoke.....



And one showing the horizontal linearity control (left), drive (center) and width control (right). They look original to me.



Currently I have to back the drive control off to its counterclockwise limit to remove the vertical wrinkles at the right side of the picture. Is there any risk of damage of the flyback or horizontal output tube if I do this?

[dcl0]

They have been mentioned before on this site (that's how I found them), but I just want to add what a fantastic source Moyer electronics is for hard to get parts. Bill was able to find for me a sound trap, an assortment of peaking coils (from which to experimentally determine the best one) and a correct field coil speaker (the one that came with the set was a smaller substitute and was eaten by mice anyway). This is much better (and cheaper!) than bird-dogging Ebay for needed parts.

[dcl0]

Just an update-success with the width problem. I replaced the mica (or micamold) capacitor C77 and the 1 M resistor R84 in the circuit providing drive signal to grid 5 of the Horizontal output tube V19. I was able to get the picture within the screen by backing width control almost completely out and adjusting the drive control until it crowded the right side of the screen and couldn't be compensated for by adjusting the width control and the horizontal centering control.

Then an interesting problem arose after I turned it on a few times. The final time I turned it on, a crackling sound, then no picture, no sound, and just a grey raster that couldn't be brightened or darkened with the brightness control. The resistor R94 was getting unusually hot for the TV being just switched on. I pulled all the insides out, back on the bench and found that the new capacitor C4B 30uF 250 Volts was a dead short. I replaced it with one rated for 500 volts, and while it was on the bench, measured the surge voltage when switched on, it surged to 333 volts across that capacitor then relaxed to 180 volts. Its interesting that both the Riders and Sams parts lists call for a capacitor rated for 250 volts. But I've used it a few times since and no problems yet.