What to do with old 5 portable UHF/VHF TV?

  • Thread starter Thread starter WarInTheHead
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AI Thread Summary
The discussion revolves around the potential uses for an old 5-inch portable UHF/VHF TV, which still powers on but does not display a picture due to the transition to digital broadcasting. Suggestions include connecting an old TV antenna and using a digital converter box to receive signals, as the TV cannot process digital broadcasts directly. Participants recommend preserving the TV as a vintage item, as it may gain value over time, and suggest researching its schematic diagrams for educational purposes. Additionally, DIY antenna construction ideas are shared, emphasizing the use of simple materials to enhance reception. Overall, the focus is on creative ways to repurpose or restore the vintage TV for practical use.
WarInTheHead
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What to do with old 5" portable UHF/VHF TV?

Hello, firstly, this is my first post, yay. I am 23 and just started school Jan 11' for electrical engineering. My grandpa was an electrician. That and reading about Nikola Tesla made me really want to study electricity. I've only taken one real "electrical" class so far, and had a horrible teacher...which was kind of sad. It's the first time I've tried in school, and I got through my first semester with 3 As and 1 B (DC circuits). This semester I will def. get all As. ANYWHO!

My friend recently cleaned out a really old garbagety house and I found a (roughly 5 inch) old Quasar portable TV. The date on it is 1980...almost a decade older than me, haha. So, my dad found a 12 V DC adapter that fit it, and behold : IT WORKS! Turns on, has sound and everything...only problem is it gets no picture. I assume with the switch to digital cable and ****, that that brought about the end of broadcasting in this format (Hell, I may be completely dead wrong about this and they do still broadcast, but this thing is broken? Am I right?)...

My question is, WHAT CAN I DO WITH THIS? I was so excited to see that it works, but I'd really like to use it for something. Is there a way to put a coaxial cable input on this beast, so I can plug my cable into it? (I assume it's black and white, but I don't know without a picture, haha) Although I'm almost a year deep in my schooling, I haven't had much "hands on" electrical experience. I do, however, have a soldering iron, solder, etc, from fixing guitar cables for my friends and I.

So, any ideas (preferably with instructions/tips attached) would be awesome! I'd love to be able to use this awesome find for ANYTHING that may be half way useful/entertaining. Thanks guys/gals!


PS http://www.ebay.com/itm/QUASAR-Portable-5-Television-TV-Radio-Perfect-/290621986011?pt=Televisions&hash=item43aa6b94db

That is ALMOST this tv. Mine doesn't have "buttons" for channels, just a regular dial to go up and down the scale, and a switch to go from UHF to VHF.
 
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WarInTheHead, Welcome to Physics Forums!

If you get an old TV antenna, some flat (300 ohm) antenna cable and connect the antenna to the TV, maybe you could get a picture. I would save it and preserve it. In the future this will be a museum piece with lots of value. Besides that, if you could get old schematic diagrams and operator's manual you could study how it works and learn lots to help you along your way. Try contacting the manufacturer.
 


""In the future this will be a museum piece with lots of value. ""

i wish i'd kept all my TI-99/4A's.

Quasar was a rather high end name as i recall.. if Grandfather has any old stereo equipment be sure to research it before he gives it away.

Practically all TV is now broadcast digital which your little TV can't receive.
i'd peruse local yardsales and thrift stores for a digital converter box and hook it to an antenna. Walmart still sells them, as do a couple other places. BUt they are common in junkshops.

images?q=tbn:ANd9GcS4ODaDwD4tBWjv3k1uiGnSYH3EN6tWMLhLxhxggDQQKnHdf4Oc%20.jpg


your folks probably have one left over- ask your friends and neighbors too, you'll find one.

then go to site antennaweb dot org to find out what channels are available in your neighborhood and what are their frequencies. The little GE converter unit above displays the frequencies for you...

then google "folded dipole antenna".

i built one out of #12 house wire and 3/4 inch PVC pipe. Cost less than $10. That style antenna matches 300 ohm twin lead or, if you solder it to an antenna transformer you can use coaxial cable. Works good to put the transformer in a tee with pipe out each side to support the wire loop, and another pipe out the bottom for a mount. Cable or twin lead comes down that pipe of course.. Attach it with conduit clamps to most anything, my building had a roof mounted airconditioner and i just put the conduit clamp under one of its side panel screws..


My folded dipole antenna is 27 inches long which worked very well for the frequencies in my town.
Make yourself a table of local stations, their frequencies and corresponding wavelengths.
Ideally your loop should be an odd number of half-wavelengths,
but a folded dipole is pretty forgiving
mine is real close to 1/2 wave for one staion
and not far from 3/2 wave for a couple more
and it works GREAT.
images?q=tbn:ANd9GcTwsmCdJvTkGSRNJczpWqXoZ34IIcrViCdoaAAbYJbKIZDsYzMbqw.png


i soldered in an antenna matching transformer (50 cents at Goodwill) and used TV coax for feeder.

oh by the way - on manuals dfor that thing google (and search Ebay) for the "Sam's Photofacts" .
Sams had a symbiotic relationship with the manufacturers and published repair manuals for the trade.
They were the best.
 
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