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#1
10-11-2007, 06:44 PM
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Got this tube type Magnavox color console today
Finally, a tube set has been found as a result to my "free pickup of non working TV's ad." The CRT was replaced in '72 with a Zenith Chromacolor (now complete with green halo). I fired up the set and it will need new power supply filters. I get hum in the sound and a weave through the picture. Also, the focus circuit appears to be not working as the picture is very blurry. At least I have HV, sweep, and color. The model number and chassis numbers are pretty faded. If anyone recognizes this chassis; please let me know. Also, if anyone has any thoughts (good or bad) about these Magnavox sets; I'd like to hear them. There are some water spots on the side of the case; but, it was free (and I'm not complaining)!
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#2
10-11-2007, 06:51 PM
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#3
10-11-2007, 09:58 PM
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'jes like tha tv, there ain't no picture
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#4
10-11-2007, 10:30 PM
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#5
10-11-2007, 10:53 PM
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Here are the side pictures. Really, this is one ugly TV. At least it was free and it does not take up much room. Oh yes, and it has that nice tube TV degaussing "thump" when it's turned on.
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#6
10-12-2007, 08:30 AM
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Your '72 Maggie
These were fine sets. Fixed a few. They had melty flybacks though. Watch the HOT cathode current especially, and get the Sams so you know precisely what the max current level is supposed to be.
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#7
10-12-2007, 11:00 AM
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Sure it needs work but that is not an ugly TV. If the cabinet is veneer it can be refinished. I really love compact consoles and that one is a diamond in the rough.
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Just look at those channels whiz on by. - Fred Sanford
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#9
10-12-2007, 02:10 PM
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I moved the set to better light and the chassis number looks like T933-04 and it appears to have been made in '68. I checked the Zenith Chromacolor tube installed and all 3 guns read almost equal and about 65% up the scale on my B&K 480 tester. The life test also checked OK. One day, I may try to remove the green halo. I'll see how bad it bugs me in operation. This set does have an instant on option. Of course, the instant on switch was turned on. The cabinet appears to be real wood (good thing). I'm sure I'll like it's looks better once I spruce up the cabinet.
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#10
10-12-2007, 09:55 PM
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Replace (or bridge) the main filter capacitor. This is what is causing the "crawl" in the picture and because B+ is low you will see a out of focus picture too. Julian
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julian
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#11
10-12-2007, 10:03 PM
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isn't the instant-on switch the one that causes fires?
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#12
10-12-2007, 10:57 PM
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Yes, I plan to replace all the power supply electrolytic caps. I'll disconnect the original can and leave it there for looks. I'll solder single section caps under the chassis. I've never heard of the instant on switch on a Magnavox causing a fire. I have heard of fires caused by the power switch on some RCA mid '60's color sets. I don't know when I'll get a chance to get back on this set. I was given 13 BPC & SPC style modern TV's by the local TV shop. I've been going through them to see what can be fixed in 10 minutes for $0. I did fix one POS 2004 27" Emerson flatscreen. Lightning blew up the filter cap and blew the fuse. After looking at the insides of that cheap made set; it just makes my appreciate the old Magnavox even more. I'm just not motivated to spend much time or $$ on a modern TV because I'd be lucky to get my parts investment out of it.
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#13
10-12-2007, 11:38 PM
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I never thought of instant-on as a fire-hazard, since it was designed to do that. Even if some sets had a 'vacation' button to shut the set down completely when going away, this was never an issue. If anything, I would be more concerned with energy consumption. Thats probably nill, though. Wouldn't leaving audio equipment on 24-7 like some folks do be more of a fire hazard, since many, many units were not designed for sustained operation? Thats my reasoning on this.
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#14
10-13-2007, 08:40 AM
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The Magnavoxes had a switch on the rear to allow for the "quick picture" feature to be on or off...I think this is a better arrangement than the "vacation" switch on the rear which just cut the incoming power or the sets which had no defeat switch at all. The channel indicator light would light dimly when the Magnavox was in quick picture mode to remind you the standby feature was on.
If the sets were heavily used, the quick picture function probably did not decrease that much tube life over what it would have had without it...of course it is nice to be able to disable it when the set is infrequently used.
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#15
10-13-2007, 11:12 AM
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Has anyone ever done any scientific study of how instant on affects tube life? I know how people often see patterns where there really is no connection (eg. cell phones and brain cancer). While I've seen instant on sets with bad CRTs, I've also seen plenty of regualr sets with bad CRTs and instant on sets with good CRTs.
Instant on would result in less thermal stress to the CRT. Many audio people believe that having B+ applied to a tube while it's warming up is bad for it. They like to warm up the heaters before turning on the power.
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