1979 Hitachi (NP9X-L chassis)

[Dreamsbeard]

I think it is a CT-1905, I say "think" because the number on the back says CT-969...but that's the Canadian model number of course.

[Findm-Keepm]

Originally Posted by Dreamsbeard

I think it is a CT-1905, I say "think" because the number on the back says CT-969...but that's the Canadian model number of course.

I've got two versions of the CT-969 manual in TIFF format, one is English, the other is bilingual French/English (de Aout 1979). PM me your email address so I can send both to you.

AGC control is off pin 12 of the HA11215A IC (may be a HA11215F in your set). R210, a 5K pot is the AGC. Rock it slightly CCW when you have buzzing to see if it helps. The little mickey-mike (1, 2.2uf and 4.7uf) electrolytics around the Video AGC chip were known to cause some problems like streaking, negative video, crappy sync, AGC overload and so on, so a recap of those might be of some help. GE used the same IF/Video AGC chip as their part number EP84X139 on some chassis, and the same caps were always bad - Marcon branded, and we replaced them as a preventative measure to avoid callbacks. IIRC, about 6 or 7, all hanging off pins of the chip.

Cheers,