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Philco Safari Problem - raster and weak sound, but no picture - please help!
Hello, everyone,
Thank you in advance for your help. I am new to this forum, but have found a lot of great info on here. I recently acquired a Philco Safari for 30 bucks at a flea market. I have never seen anything like it before and had to buy it (and one of the reasons I found this great forum!). I was disappointed to find that it doesn't work properly. It produces what seems to be a full raster, but has absolutely no image (just a grey rectangle - see attached picture). There is also weak/scratchy sound that comes through when I inject a signal from my DVD/modulator combo, but no picture. I replaced the electrolytic, bipolar, and paper capacitors, but no significant improvement. I took some voltage readings, and it seems some things are off. According to the service manual I found, there should be a -6.5v, -5v, -11v, and +11v source (all VDC) for the boards. I measured the -6.5v source at the filter cap and got a reading of -5.6v I measured the -5v source and got a reading of -4.5v These seem a bit low...but not as bad as the +/- 11v sources, which measured 8.35 and -8.85v respectively. I have attached the portion of the schematic that shows the +/- 11v sources. It seems this voltage is derived from the flyback transformer. I also checked the voltages at test points 1 - 5 on the boards. I have attached clips of the service manual that describe what the test points are and what voltages should be. Test points 1 and 2 were spot on. These are on the sweep board. Both measured around -.35vdc, which is exactly right according to the service manual. However, test points 3 - 5, which are on the video/sound board, are all way off: Point 3 should be +1.5v; it read -.18v Point 4 should be +10v; it read 7.44v Point 5 should be +.05v; it read -.05v It just seems like the video/sound board isn't getting enough power, but I don't know why the +/-11v supply is so low. Any help would be very appreciated. I would like to get this set to work. :-) Thanks! |
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