CTC-4 Director 21

[SwizzyMan]

Great, now I have even less height and now fold over! Looks like I need to retrace my steps here. All I did was replace a cap. I did clip the leg of a few resistors and soldered them back in. I will start by checking my connections on the resistors and cap.

[old_coot88]

I would run the vert. hold stop-to-stop before diving into it again. It may be locking at an odd sweep rate.

Also, on the line voltage issue, measure the heater voltage. If it's running signifigantly above or below the nominal 6.3 VAC, it'll tell you whether the line voltage is kosher or not.

[SwizzyMan]

Originally Posted by old_coot88

I would run the vert. hold stop-to-stop before diving into it again. It may be locking at an odd sweep rate.

Good thing I traced my work back because I forgot to solder a cap back in circuit. All is fine now. Linearity isnt great but I got it as best as I can. I still think I might lower the value of r119.

[old_tv_nut]

Did you check L71 and R68 also?

Edit: also R69, L70, and the contrast control - these are all things that load the input or output of the delay line and need to match the impedance properly to prevent echos.

[SwizzyMan]

Originally Posted by old_tv_nut

Did you check L71 and R68 also?

Edit: also R69, L70, and the contrast control - these are all things that load the input or output of the delay line and need to match the impedance properly to prevent echos.

Everything tests fine except for maybe the contrast control. It reads 21ohms at full clockwise and about 1k at full counter-clockwise. I dont think that is right.

[old_tv_nut]

You didn't say which terminals of the contrast you are connected to, but if you don't disconnect one end, you will read a bunch of other things in parallel, particularly the delay line and its 1.2K input resistor. So, the 1K reading is probably normal or close to it for an in-circuit reading. I would just wait to see what the replacement coil does for your ghosting, rather than disconnecting things unnecessarily.

[SwizzyMan]

Just ordered new coils and resistors. Found another coil that was bad L94 that read about 1 meg when it should be 27 ohm.

[timmy]

Wow that set is going to be better then originally new once it's done, lots of troubleshooting. Looking good keep at it .

[miniman82]

This can also be caused be improper termination of the delay line, check all parts for value on either end of it.

[SwizzyMan]

So adding the 180uh choke in place of the open one (L72) makes the ghosting WORSE! Ugh! Something else has to be causing this then. Left photo is with no coil, right is with coil attached in circuit.

[old_tv_nut]

Suggestions:

1) make sure the value isn't off by a decimal place or something
2) check for open resistor in parallel with either L72 and/or L71

If it's not those, check all other parallel L-R combos in the video amp chain.

[SwizzyMan]

Originally Posted by old_tv_nut

Suggestions:

1) make sure the value isn't off by a decimal place or something
2) check for open resistor in parallel with either L72 and/or L71

If it's not those, check all other parallel L-R combos in the video amp chain.

Value is fine. Checked all coils and resistors that may be in parallel with them and they all check fine except for a coil on the B-Y amp that reads 1.2 meg, but I dont think that one really matters for my current problem. I hope its not the delay line causing this!

[old_tv_nut]

Originally Posted by SwizzyMan

Value is fine. Checked all coils and resistors that may be in parallel with them and they all check fine except for a coil on the B-Y amp that reads 1.2 meg, but I dont think that one really matters for my current problem. I hope its not the delay line causing this!

Are these components on a PC bOard? Maybe a bad solder joint? Try bridging a resistor directly across the coil?

[SwizzyMan]

Originally Posted by old_tv_nut

Are these components on a PC bOard? Maybe a bad solder joint? Try bridging a resistor directly across the coil?

All point to point wired. Resistor did nothing. I think I will just get the color set up and worry about this later, maybe I'll think of something while Im doing that.

[SwizzyMan]

Now on to the color for now. Everything seems to be fine except for colors with magenta. As you can see the magenta bar fades off into red which I attribute to bad phasing in the G-Y(?) channel. I just am not sure how I would fix it (Phasing adjustment?).