After more testing everything in the sound circuit measured ok so I proceed to make adjustments to the 2nd sound IF and quadrature (L18 and L19) per SAMS and after several turns of the quadrature coil the sound cleaned way up. I was surprised the coil was off so much as components ahead of this coil measured good.
With a full raster and sound ok my next task is getting the horizontal output tube running at a safe current. SAMS does not list a max current, elsewhere I have read under 200ma is good, 210-215 at max. My set is over this and don't know where to look next, please advise. I will also report back with other voltage & current measurements on the horizonal tube to see how they compare with what the SAMS schematics shows.
- Using an analog meter with a .1uf cap across the meter
- Line voltage of 122v yields a horizontal current of 240ma
- Dropping the line voltage down to 108v yields 210ma
- All of the horizontal circuit film capacitors have been replaced
- All other caps in the horizontal circuit measure ok
- All resistors in horizontal circuit measure good, only R119 out of spec and needed replacement
- Horizontal tube is a 6JS6C measuring very good
- Horizontal AFC/Osc/Discharge tube is a 6U10 and also measures very good
- High voltage set to 25kv
- Horizontal linearity adjusted to the dip and then raised off the dip ever so slightly
04-14-2023, 07:55 PM
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