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Old 06-17-2021, 04:29 PM
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DavGoodlin DavGoodlin is offline
Motorola Minion
 
Join Date: Aug 2011
Location: near Strasburg PA
Posts: 3,413
75 watts at 120v! Here is "OTA" reception shown from a channel 7 modulator. The 8 presets tune VHF and UHF. I have no idea what the horizontal (oben?) and "vertikal" scan frequency is for PAL. It tunes like a Zenith CCII one knob - shows as dirty channel adjust pots, in this case those 10-turn jobs.

It seems when you push the CRT socket/PC board on, it broke the filament connection because the socket was not fully seated when it was wave soldered. This was found after HV was confirmed after replacing that 2N3055 B+ reg. That is when I took the picture with my crappy cell that screws up all pictures in some way.
Saba Pro CP41 color H first light.jpg
Several mods were made as several transformers and coils have cores spun half out of the coils. It is obvious this set was never designed to use 120-60 but the attached schematic (schaltbild) shows 220 v only. The power transformer has to be 120 ( I got 6.3v on CRT htr winding) but has no markings anywhere. I was able to adjust the 20 volt source and 12 volts was always right on.
Saba Pro CP41 color H sweep.jpg
Oddly the only other PS mod I saw was a 300mf/350v Mallory computer-grade cap paralleled across the input reactor that feeds a rectifier and SCR directly from line. Thus, its a hot chassis set. The SABA design is more like a Sony than anything made in USA by early 70s.

The 175 volts was measured at 140, I max-adjusted it up to 173 and the sweep got better, as the sweep-derived 24v to the vertikal increased and I adjusted to compensate, popping one of the outputs.

It was fun playing and adjusting but the vertikal sweep quit and I have another shorted transistor (T220 by Telefunken BD175) that I probably have a sub for but a matched pair may be better as its available as NTE 184 MP.
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