Motorola roundie

[Yamamaya42]

Originally Posted by old_tv_nut

Ok, I'm blind - where is A20 on the schematic?

Took me a wile to find it also! below the R-Y amp, under C142, had not seen one used before that was adjustable.

[old_tv_nut]

I think the alignment instruction for A20 in the SAMS must have a mistake. This trap couldn't possibly affect pin 6 of the burst amp. The place to look with a scope would be the plate of one of the three color amps (pin 1 of V25, V24, or V20). Actually, you shouldn't need a scope at all, just look for minimum crawling dots on the screen in colored areas.

I looked at Forest Belt's book, which has a schematic for the TS-907B chassis. That version does not have the 3.58 trap, and indicates that L37 and L38 filter out the 3.58 MHz.

[Yamamaya42]

Originally Posted by old_tv_nut

I think the alignment instruction for A20 in the SAMS must have a mistake. This trap couldn't possibly affect pin 6 of the burst amp. The place to look with a scope would be the plate of one of the three color amps (pin 1 of V25, V24, or V20). Actually, you shouldn't need a scope at all, just look for minimum crawling dots on the screen in colored areas.

I looked at Forest Belt's book, which has a schematic for the TS-907B chassis. That version does not have the 3.58 trap, and indicates that L37 and L38 filter out the 3.58 MHz.

Another thing I find Weird in this Sams, for the Color AFC setup, it says to turn the color killer full clockwise, but on other sets I have seen, it says to set it full CCW, is this an error? or is full off for the killer full clockwise on this set?

[old_tv_nut]

Originally Posted by Yamamaya42

Another thing I find Weird in this Sams, for the Color AFC setup, it says to turn the color killer full clockwise, but on other sets I have seen, it says to set it full CCW, is this an error? or is full off for the killer full clockwise on this set?

I guess we have to ask the man who owns one.

[timmy]

I don’t like taking chances but if I can find an Allen wrench that fits right and tight snug then I’ll see if these slugs will move but every wrench fits to loose and that alone being loose will break the slug I have a spare slug but if it breaks i won’t be able to get it back where it was.

[Yamamaya42]

they do make one of the exact size you need, the same size of the alignment tool, but its only to be used to heat the stuck inside core, you then use the plastic one to turn it oncen its heated.

1. put in allen wrench,
2, heat allen wrench with soldering iron, or other type device to heat core.
3 , remove allen wrench, and try to see if core will move with alignment tool, you may need to use solvent.

repeat.

[timmy]

These plastic adjusting tools can break easy or with a heated core the tool may slip then that’s the end of that

[Yamamaya42]

Those readings of voltages that were NOT in spec of +12 and -12 at V22 are proof that things are out of alignment, and unless A19/A18/A17 can be correctly adjusted, it will continue to give you problems.

You can keep looking for parts out of spec, but you will be unlikely to find any. That is not to say new parts in the area won’t help, but, 95% of your problem is not being able to set the color section alignment correctly.

And as old_tv_nut pointed out, the voltages you saw at the phase detector are a key sign of this.

[timmy]

And is it possible that the if alignment that i had touched in the beginning have anything to do with this color thing even though I get a great picture.

[zeno]

Originally Posted by old_tv_nut

I guess we have to ask the man who owns one.

Packard !

[Yamamaya42]

Originally Posted by timmy

And is it possible that the if alignment that i had touched in the beginning have anything to do with this color thing even though I get a great picture.

It very well could, there is a reason the alignment steps are numbered 1-8, each has an effect on the other in a way from very subtle to drastic, setup is a long delicate dance of back and fourth, up and down, round and round, you skip steps, jump around, and you can get odd results, very much like what you are seeing.

[timmy]

Originally Posted by Yamamaya42

It very well could, there is a reason the alignment steps are numbered 1-8, each has an effect on the other in a way from very subtle to drastic, setup is a long delicate dance of back and fourth, up and down, round and round, you skip steps, jump around, and you can get odd results, very much like what you are seeing.

Well you do make sense but in the beginning all was fine it’s only when it started acting up so the IF alignment didn’t change I haven’t touched it so still something triggered this condition. And the color IF I’m sure that didn’t change I haven’t touched that either if all was good befor then it still seems logical that a cap or resistor went bad bad somewhere.

[Username1]

Originally Posted by timmy

I don’t like taking chances but if I can find an Allen wrench that fits right and tight snug then I’ll see if these slugs will move but every wrench fits to loose and that alone being loose will break the slug I have a spare slug but if it breaks i won’t be able to get it back where it was.

Here are two ways you can try to get a slug moving again using a metal
allen key. Try and get a few turns of aluminum foil wrapped around it
before putting it in the slug - see if it gets snug enough as to not
turn inside the slug & break it. I believe the slugs break from
the Allen Key turning inside the slug kinda forcing to to
expand as it skips.... Or you can just epoxy it into the
slug and take it out & insert a new one - Put some
chapstick on it before you put it back. Wax makes
a great dry lubricant.

You have to be careful with epoxy in the slug - make sure
none gets anywhere along the threads.....


.

[Penthode]

I am very weary of stuck slugs. It is heat over time which makes it stick tight.

I have closeto 100% success by using a heat gun with a nozzle I constructed to focus the warm air towards the slug. Careful application of heat melts the wax and frees up the slug without risk of splitting it.

I have even had success with heat removing split slugs.

[timmy]

So when doing resistance checking at the tube sockets am I correct in saying check with tubes in place ?