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#1
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Help diagnosing Motorola Quasar/WU821FS
Hello Guys,
Great forum here! I just picked up this old Motorola Quasar model # WU821FS The audio comes through great, but the picture is nothing but snow, and occationally a black bar on the bottom warbles it's way through with a thin green line above. I'm really a novice with old tv's(this is my first purchase, got it cheap). I'm wondering if you all could get some sort of feel of what the issue might be by taking a look at the pic w/ the set turned on. Thanks to Dave at JustRadios, I was directed to a schematic over at Sam's. I'll be getting one of these for any future servicing needs. It appears that the last time this television was serviced was 1982 w/ a 2 year picture tube warranty. I am the 3rd owner, but the 2nd owner received it after moving into the house (1st owner left it there), and had it stored away from the get go. Thanks for any help! |
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#2
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I would say bad capacitors in the vertical section...check vert. output tube too if it is the tube type. make sure you follow all safety precautions on dealing with high voltage in TV's if you go in to working on it, as it can be very dangerous.
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#3
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Hey Chad,
Thanks for the quick response. This solution would be for both the lack of any reception AND the black bar issue, right? On the back, everything pops off nicely w/ the little tabs, but the left side does not because it looks like the rear control panel has been tacked in, thus I cannot remove the back board. |
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#4
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I've attached a few more pics of the rear of the unit. As you can see from the rear control panel, it seems to be tacked shut.
Also, I'm curious to know what the cutout w/ the metal piece is on the lower left area? Thanks |
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#5
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That is the lock for the drawer...this is a Works in a drawer set and you release that latch to slide the drawer out to the front. Most of the circuitry is in the drawer.
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| Audiokarma |
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#6
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I'm trying to figure out how to release this latch? Any tips?
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#7
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It seems like you have to push down or pinch in the two sides of a bar going across the latch. I hurt my hand on it the last time I did it so I would recommend putting on gloves while pressing the latch release.
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#8
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Look for the FA board. If not mistaken, this has the 6CW5 vertical output tube on it, and the horizontal oscillator tube. 6CW5's can cause lots of issues.
I have not seen one of these sets in at least 20 years. ![]() If not mistaken, you need to remove that 1/4" hex screw near the power connector before you pull the drawer out the front of the set. I can see it in your pics. Last edited by holmesuser01; 08-15-2005 at 06:20 PM. |
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#9
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Isnt there supposed to be some kind of jumper on the 75 ohm input in order to use the 300 ohm input on these? This might be the cause of the reception problem. Has the uhf been tried yet? Most of the tv's that i have had that produced snow functioned properly once proper signal was applied unless tuner was extremely dirty.
-Tony |
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#10
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I have it on UHF at the moment, and it only picks up audio from some strange 3ABN (3 Angels Broadcasting) channel that kind of freaked me out in a Poltergeist sort of way...hah.
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| Audiokarma |
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#12
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I haven't seen your video because all I have is dial-up. But if the line crawls it is could be a capacitor in the vertical section. In particular, look at the cathode circuits in both the vert output and oscillator.
If there is no crawl but just bad height and linearity it could be a bad tube or off value resistor in the vertical circuit. Also, pay attention to any other clues such as a slow crawl that warps the picture which would then indicate bad power supply filtering. |
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#13
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I used to have almost this exact set. I can't remember for sure, but arent the height and vertical linearity controls on the end of the vertical board? Don't you have to open the drawer to adjust them? Maybe this will clean up with just adjustments.
AFAIK all Motorola Quasars came with a schematic and service information. It's probably taped inside the cabinet. John |
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#14
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Hmm this might save me $20 on buying the schematic booklet.
So in order to pull the drawer out, I need to remove the hex screw? Is it the metal one on the paper panel, or the plastic one? |
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#15
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I believe you need to remove the metal screw right below the antenna terminals.
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| Audiokarma |
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