My CTC-16XL Project.

[Yamamaya42]

Worked with convergence PCB a bit last night, new diodes had very little / no effect, still can't get R/G at the top as good as left/ right/ bottom, ( perhaps never will, IDK ).
Moving the conv, yolk forward/ back a bit did not help much.
Have NOT tried the new caps in it yet, will try tonight to see if it changes anything.
The biggest problem I see is the R/G horz top lines are not linear, red above green in one side, and then green above red in the other, this is not seen anyplace else, the R/G can ALMOST be lined up, but is slightly still off.

[old_coot88]

Originally Posted by Yamamaya42

Worked with convergence PCB a bit last night, new diodes had very little / no effect, still can't get R/G at the top as good as left/ right/ bottom, ( perhaps never will, IDK ).

Moving the conv, yolk forward/ back a bit did not help much.

For the heck of it, check where all the wires connect to the conv. yoke coils. There was a similar problem one time, caused by one of those wires being broke right at the connection point.

[Yamamaya42]

caps replaced, Resistors ( normal not adjustable seem OK )
only slightly better.
https://imgur.com/Qs1PUZS
https://imgur.com/jtYPypZ
https://imgur.com/rcdsYk4

aside from replacing potentiometers, there is not much more that can be done,

It's pretty close for such an old set.

[old_tv_nut]

Is the R/G vertical left potentiometer at one end of its range?

If so, have you tried setting the R/G vertical left potentiometer to center, then adjusting the R/G vertical right coil, then readjusting the R/G vertical left potentiometer?

[Yamamaya42]

Originally Posted by old_tv_nut

Is the R/G vertical left potentiometer at one end of its range?

If so, have you tried setting the R/G vertical left potentiometer to center, then adjusting the R/G vertical right coil, then readjusting the R/G vertical left potentiometer?

the only one at the end of range is r27 R-G vert lines top ( not replaced ) X6 r270 new
adjusting will NOT get it in range
R26 does work on the bottom.

all other adjustments seems to have normal range

[old_tv_nut]

Have you checked C4 and R106, that couple the vertical waveform from the cathode of the vertical output?

[Yamamaya42]

Originally Posted by old_tv_nut

Have you checked C4 and R106, that couple the vertical waveform from the cathode of the vertical output?

I replaced C4 a long time ago, when i replaced the majority of the electrolytics, r106 is still original. that may be it


edit--

yeah, and the damn thing would have to be hidden under the chassis

not going to be changing any time soon, don't wanna pull it out a 3rd time in 1 week.

[freakaftr8]

Somehow I always get lucky with convergence on these old sets. Never had to get into the convergence board. Knock on wood. My CTC16 seemed to converge well with your same oddball issue. R27 r/g vertical top is almost at the end of its range but able to achieve good convergence.

[Electronic M]

Originally Posted by Yamamaya42

I replaced C4 a long time ago, when i replaced the majority of the electrolytics, r106 is still original. that may be it


edit--

yeah, and the damn thing would have to be hidden under the chassis

not going to be changing any time soon, don't wanna pull it out a 3rd time in 1 week.

I remember when I started restoring color sets with my CTC15 and hit the troubleshooting stage that 3 chassis pulls in a day was a low number.... Tip: there are a couple of screws or holes for them on either side of the power cord interlock , and there should be a matching set of half circles on the tuner/control subchassis. They are for bolting the subchassis to the main chassis to make pulling and installing the chassis for short tests easier.

[Yamamaya42]

Originally Posted by Electronic M

I remember when I started restoring color sets with my CTC15 and hit the troubleshooting stage that 3 chassis pulls in a day was a low number.... Tip: there are a couple of screws or holes for them on either side of the power cord interlock , and there should be a matching set of half circles on the tuner/control subchassis. They are for bolting the subchassis to the main chassis to make pulling and installing the chassis for short tests easier.

https://imgur.com/Txm8oBx

If you look closely at it when I had it on the bench last week, I had the tuner there while I was working on it, till I removed it to hook up the bar-dot input.
Nevermind that I like to add new parts ( caps & such ) with silicone :p as long as it can't be seen from above!

New r106 & c4 ordered , replacing c4 again, as it was not EXACTLY @ 50 uf, but a bit higher, that may or may not also be an issue, this time, getting precisely what it says on SAMs is a replacement , 75-TVA1414-E3.

In no big rush to replace them, so using ultra cheap shipping from Mouser, $3.30 vs $7.50, meaning rather than get it tomorrow, it will be here Sat.
Will stick the back on it for now and wait for another weekend to put them in.

Which does bring up a un-related topic, the 2 metal clips for the back have been missing since forever, what can be used in their place?

[Yamamaya42]

The resistor info for the resistor off the vert out cathode is a bit confusing.
The SAMs schematic shows r106 to be 5.6k 3w, with alt parts of irc resistor pw5-6000 6k 5 watts, & workman 3g-5600 ( 5.6k 3w)

The CTC-16 (not x) shows it to be 5w.
both have the same RCA part # for the resistor, 104180.
But the SAMs for the XL clearly shows 3w, and lists a part # shown on others listed as 5w, so what is in it? Does it not matter?


edit---
https://imgur.com/UbSRwgB
what i find so confusing
r106 vs 105 16xl- 16
same location on schematic, shows same RCA part number, why is one 5w and one 3w

[Electronic M]

Originally Posted by Yamamaya42

The resistor info for the resistor off the vert out cathode is a bit confusing.
The SAMs schematic shows r106 to be 5.6k 3w, with alt parts of irc resistor pw5-6000 6k 5 watts, & workman 3g-5600 ( 5.6k 3w)

The CTC-16 (not x) shows it to be 5w.
both have the same RCA part # for the resistor, 104180.
But the SAMs for the XL clearly shows 3w, and lists a part # shown on others listed as 5w, so what is in it? Does it not matter?


edit---
https://imgur.com/UbSRwgB
what i find so confusing
r106 vs 105 16xl- 16
same location on schematic, shows same RCA part number, why is one 5w and one 3w

If you can't spec the same wattage resistor always go up in wattage not down...they probably did that.

Also when replacing a high watt power resistor that tends to get hot in a restoration scenario it may be better to choose a higher wattage part than original as that will make the replacement run cooler.

[Tomcomm]

If you can't spec the same wattage resistor always go up in wattage not down...they probably did that.

Also when replacing a high watt power resistor that tends to get hot in a restoration scenario it may be better to choose a higher wattage part than original as that will make the replacement run cooler.

[tubesrule]

How does using a larger wattage resistor make it run cooler when the exact same wattage will be dissipated in it based on the usage? Other than the larger wattage resistor may or may not have slightly more surface area (unless you are changing to a chassis/heatsink mounted type or greatly increasing the physical size), it will run at the same temperature. The thermal resistance in free air will not be that much different and that, along with the watts dissipated is what determines the temperature.

[Yamamaya42]

i will most likely stick a 5w in there, no matter what is/was in there, i just find it weird that both the 16 and the 16XL show the same RCA part # in SAMS, but have different watt values, one would think the 3 watt one would have one RCA # and the 5watt, another, who knows what they were thinking 50+ years ago :O