CTC-4 Director 21

[SwizzyMan]

Originally Posted by old_tv_nut

Hmm... can you measure the high voltage? If it's high, it may reduce the scan size.

Also, if you have a variac, try adjusting the line voltage.

Now that you mention it. I have been running the set off my PR57 and when the set is at full operation it does drag the line voltage down about maybe 5 volts. I never thought of adjusting the line voltage after the set has warmed up. This may be the source of my lack of height.

[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.

[SwizzyMan]

I have been working on solving a ghosting issue in the picture. Checking resistors on the IF board only revealed 2 out of tolerance resistors. Two 68 ohms coming off the cathode of the 6az8 IF tubes then to ground. Next thing I suspected was the 1n60, but it tests fine on the diode test. Should I still replace it? I need to check around the video amp tubes now.

[SwizzyMan]

Found an open inductor on the video out tube. L72 on sams 180 Microhenry 9.5ohm. Is this an appropriate replacement? http://www.mouser.com/ProductDetail/...o%2f1lu29zY%3d

[old_tv_nut]

Originally Posted by SwizzyMan

Found an open inductor on the video out tube. L72 on sams 180 Microhenry 9.5ohm. Is this an appropriate replacement? http://www.mouser.com/ProductDetail/...o%2f1lu29zY%3d

Looks like it should work fine.

[old_coot88]

Originally Posted by SwizzyMan

I have been working on solving a ghosting issue in the picture.

By ghosting, do you mean ringing (parasitic amplitude ripples tagging after fine detail in the pic)? If so, try subbing the last IF tube if you haven't already. It can cause ringing even if it tests good on a tester.

[SwizzyMan]

Originally Posted by old_coot88

By ghosting, do you mean ringing (parasitic amplitude ripples tagging after fine detail in the pic)? If so, try subbing the last IF tube if you haven't already. It can cause ringing even if it tests good on a tester.

Yes. I believe I did try subbing that tube with no difference.