#1
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Zenith A3720W1
How would I open up the back of this television because there are knobs on the side?
I am also interested in any pdf of the schematics, any brochure with it, and any other paperwork of it. |
#2
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The side knobs just pry off. There may also be a white knob on the back marked "peak picture". Pry that off too.
The side knobs sometimes are captive so they will just hang off. Dont forget to remove any wires from the antenna terminal board. When opened you can get the chassis number. Its usually on a tag pasted to the HV cage. Its what we go by as a rule. 73 Zeno LFOD ! |
#3
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From the 1970 catalog
A3720W ( walnut) the Raeburn. Also available A3720P in pecan finish. A cheaper model A3710J in tan cabinet & no dial lights also offered. The chassis was also used in 14" sets. Chassis built between 1969 & apx 1976, a long run. 16" sets phased out abt 1974 & replaced with 17" solid state sets. 14" models phased out 1976 & replaced with the 13" solid state set. Later sets had AFC, high focus voltage CRT, Chromacolor CRT & remote in better models. 73 Zeno LFOD ! |
#4
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I have removed the knobs on the side and now I am stuck on removing the plug.
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#5
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Quote:
Nice Zenith btw, I have a very similar one which is the main TV in my house - I've had it for 25 years, it was my first vintage tv, first tv in general, and the reason I signed up for this website. It's capable of a very nice picture when it's working right. Also don't forget the screws on the bottom of the TV, as well as all those on the back. Last edited by maxhifi; 03-11-2019 at 04:19 PM. |
Audiokarma |
#6
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So I have cleaned the dust off the chassis and checked if any tubes were not fully in their places. I tries to test the television and this is the result.
Also, is any want the chassis model, it is 12A10C15. |
#7
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Looks like a bad CRT or video problem. Be sure you didnt knock
any of the plug in transistors loose when dusting. Also run it for 3-4 hours & see if it slowly gets better. If so that points to the CRT. 73 Zeno LFOD ! |
#8
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You might be missing luminance.
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
#9
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clean and or check the service switch
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#10
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Loss of luma can also be heater-cathode short in the CRT. Tapping on the neck will usually show it up.
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Audiokarma |
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