#16
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The larger sets are here https://www.radiomuseum.org/r/saba_s...r_telec_2.html
The smaller TV is this one https://www.radiomuseum.org/r/saba_p...mputer_cp.html So far, it looks like only the antenna F-connector is a clue besides the US plug. Inside, I also found a 300mf 350v Mallory cap had been added to the power supply. https://www.youtube.com/watch?v=krD4hdGvGHM Cold checks always before power up's ! I agree with Shang066 its not good to slowly raise line on a SS TV! Sweep circuits do not operate at lowered line voltages and other self-diagnostics, however primitive, will not always activate linearly. First, all 3 fuses were OK; one 2A at primary and two on secondary's of the power transformer. I used my new toy (Peak ESR 70) to test the e-caps, checked most power transistors and driver transistors with Fluke, touched up some solder joints on the sweep board under stress-producing cable plugs and transformers, etc. This reminds me of a some USA sets-circuitwise, but not a GTE product. On the PS board, one 10 mf electrolytic cap tested open, one regulator transistor 2N3055 shorted E-C, and only one high ESR 4.7 mf cap on the sweep board. I felt confident it would either work or sort of try to work and it did. Drawing just 26 watts at 120v with static from the speaker confirms voltages measured. There is a 12v (5.5v meas) 20v (18v meas) and 174v (105v meas) source voltage per the schematic, but no signs anywhere of a two-primary power transformer, additional fuses or taps. Otherwise it looks stock with a USA plug!
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"When resistors increase in value, they're worthless" -Dave G Last edited by DavGoodlin; 06-14-2021 at 03:21 PM. |
#17
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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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"When resistors increase in value, they're worthless" -Dave G |
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Quote:
N.b., in the PAL world they usually refer to these as "line" and "frame" rather than horizontal and vertical. Frequencies are fairly close to NTSC, 15.625KHz and 50Hz. All of my NTSC sets here will sync right up to a PAL signal, sometimes requiring adjustment to the V and H hold, sometimes not. No color, though, of course. |
#19
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Quote:
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"When resistors increase in value, they're worthless" -Dave G |
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