Can I use a JCPENNY Solid State TV as a monitor? - Page 1
Forum section: electronics / beginners

author: mrwide49
author_rank: Newbie
timestamp: March 18, 2025, 02:04:06 am
content: Hi! I found a JCPENNY Solid State TV at a garage sale and the owners let me have it for free as long as I could get it out of their garage haha. I talked with a buddy, and he suspects that it may be a CRT and that I may be able to use it as an external monitor for my computer or my TV. I plugged it in, and it works fine. It's in black and white which I'm pretty sure I can't do anything about but I can deal lol. I am fairly new to this field of expertise so I am completely unaware as to how I would get started on adapting this almost 50-year-old machine to work with my stuff todayOn the back, it has labels that read:MANUFACTURED JULY 1977TQF 83593130FKJJCPENNY Solid State TVMODEL NO. 685-1022AC 120V 35WProduct Service No. 685-1022-10Part No. TBM 83673CHASSIS FAMILY: T124-1 (TQF83825)SERIAL NO. FF7432609On the front, there's 3 knobs. The top one is an Off/Volume one which turns the TV on and increases/decreases the volume. The middle knob is Contrast, and I actually don't know what it does, but the screen does start goofing around when I twist it. The bottom and final knob is Bright, and it ofc increases/decreases the brightness of the screen, which is actually pretty cool for people watching stuff at night. To the right of these 3 knobs are two much bigger ones with handles. The top one I'm not sure what does, but around the knob is a circle of numbers that go from 14. It goes up by twos all the way up till 82. The bottom knob I'm also not sure what is. But around it is a circle of 13 options. It starts at U??? Then goes around clockwise to 13. These options also change the screen. The only other thing on the front is an audio port that the aux on my headphones can plug into and connect to (surprisingly).On the back, It has two switches that each say ROD on the left, and EXT on the right. Above them it says UHF, and on the bottom is VHF. I really don't know what these 2 do either. At the bottom of the back has 2 small knobs labelled V-Hold and H-Hold respectively. I think they're supposed to change the picture of the screen somehow, I'm not sure haha. To the right of those two there's (I believe) 3 other ports labelled Height, V-Lin, and RF-AGC. I'm assuming that if I had to plug something into this TV to convert it, it would be through one of these 3 ports.Sadly, I do not know how to, nor if I can even use this thing for anything visual wise. Any explanationsor help would be greatly appreciated!!!

author: Andy Chee
author_rank: Super Contributor
timestamp: March 18, 2025, 02:16:40 am
content: The easiest method to get something onto the screen is to use an RF modulator.For example, random Amazon search;https://a.co/d/07MlCgU(composite input)https://a.co/d/jhy0joX(HDMI input)You'll also need a 300 ohm - 75 ohm balunhttps://a.co/d/4veDdLW

author: themadhippy
author_rank: Super Contributor
timestamp: March 18, 2025, 02:53:42 am
content: Quoteyou can.easiest would be the modulator mentioned above,more fun would be to drive the deflection coils from an external audio source but lethal voltages roam about inside waiting to bite so unless your 101% confident in what your doing leave well alone

author: amyk
author_rank: Super Contributor
timestamp: March 18, 2025, 03:05:22 am
content: Yes, you can use it as a computer monitor. The highest resolution you're likely to be able to use with it is around 320x200, i.e. CGA.

author: bdunham7
author_rank: Super Contributor
timestamp: March 18, 2025, 03:19:01 am
content: You need one of these:https://www.ebay.com/itm/116506395307?_skw=dtv+converter&epid=150049229Edit: to be clear, this is to receive broadcast TV, not convert it to a monitor. I don't think you understand how bad this will look as a monitor...it is more suitable for I Love Lucy reruns.

author: mrwide49
author_rank: Newbie
timestamp: March 18, 2025, 03:26:27 am
content: Quote from: themadhippy on March 18, 2025, 02:53:42 amI only heard of any of these terms in the last hour, so based on that I can fairly say that I'll leave EVERYTHING not on the outside aloneThank you three for your help! From what I can gather, the 75 Ohm to 300 Ohm Adapter has these 2 hook thingies ill connect to either the VHF or UHF (i actually don't know lol, any help on this part would be appreciated), by unscrewing the screws covering whatever those tab thingies are and placing the hooks between them. Then I connect that to the HDMI RF Modulator, which then connects to whatever I use this thing for lol

author: Analog Kid
author_rank: Super Contributor
timestamp: March 18, 2025, 03:36:18 am
content: It'll work with an RF modulator as suggested: however, don't expect anything great.In fact, the image quality will be quite crappy compared to whatever real computer monitors you've seen.(320x200 is definitely low-res.)However, it can still be a fairly kewl li'l project. With the right computer you could even play (old) computer games on it.

author: mrwide49
author_rank: Newbie
timestamp: March 18, 2025, 04:32:09 am
content: Quote from: bdunham7 on March 18, 2025, 03:19:01 amThis is actually crazy news to me, I didn't actually know you could still receive any broadcast TV in 2025! Is there a guaranteed set of channels it'll be able to pick up for me? Or would it simply depend on how great it can pick up any signals from everywhereQuote from: bdunham7 on March 18, 2025, 03:19:01 amQuote from: Analog Kid on March 18, 2025, 03:36:18 amQuote from: amyk on March 18, 2025, 03:05:22 amThank you very much for these warnings, but I am honestly still blown away that this piece of equipment almost half a century old can still be used today, so I'll take anything haha. I might use it for a cute second monitor for whenever I wanna have my Xbox and computer on at the same time

author: Andy Chee
author_rank: Super Contributor
timestamp: March 18, 2025, 04:42:16 am
content: Quote from: mrwide49 on March 18, 2025, 03:26:27 amHave a closer look at the picture;https://a.co/d/07MlCgUCH3 & CH4 is a selector switch that allows you to choose the RF modulator output to be VHF CH3 or VHF CH4. This modulator needs to be connected to the VHF terminals on the back of the TV. Once all the cabling is connected, simply turn the VHF channel selector knob on the TV (the bottom big knob from 2 to 13) to either CH3 or CH4.Other modulators may be UHF and/or have different channels. For a UHF modulator (again, check the modulator specifications/instructions), connect the modulator to the UHF terminals at the back, select U on the bottom knob, then select the appropriate UHF channel with the upper knob.Before you buy one, let us know which one you buy, so we can double check it'll work.

author: Analog Kid
author_rank: Super Contributor
timestamp: March 18, 2025, 05:12:14 am
content: Quote from: mrwide49 on March 18, 2025, 04:32:09 amYou can use that set to view over-the-air TV.However, you'll need more than just an antenna to receive them.When that set was made TV signals were sent over the air as analog signals.Today TV signals are still sent over the air on the same frequencies (channels) as before, but they're now digital, not analog. So all you'll see on the screen is basically noise.You'll need a set-top digital converter box, which I think you can still buy. (The one I had back in the 2000s was one I got for cheap at the time when the change-over to digital happened; you could send in a coupon and get a box so you could use your old analog TV to watch digital programs.)Like a RF converter, it just connects to the TV's VHF antenna terminals and uses channels 3 or 4, with tuning done by the set-top box.

author: bdunham7
author_rank: Super Contributor
timestamp: March 18, 2025, 01:48:31 pm
content: Quote from: mrwide49 on March 18, 2025, 04:32:09 amYou may not get much in your area with simple rabbit-ears or short wires, but if you put up a decent antenna you'll probably get a lot of stations.

author: BrianHG
author_rank: Super Contributor
timestamp: March 18, 2025, 02:18:46 pm
content: Quote from: amyk on March 18, 2025, 03:05:22 amFor a monochrome CRT which doesn't contain a color subcarrier filter, expect 640x240 if your video source was monochrome, especially if you bypass the TV's internal tuner.If you do not mind interlaced video, then you can expect 640x480 with the above specification.To get the full 240p or 480i, you may need to squish the vertical size of the TV through an internal adjustment on the TV's circuit board as the extra ~40 lines of video are usually in the overscan area of the display.

author: bdunham7
author_rank: Super Contributor
timestamp: March 18, 2025, 03:00:45 pm
content: How could we forget this?https://www.ebay.com/itm/187054786420

author: Rick Law
author_rank: Super Contributor
timestamp: March 18, 2025, 06:27:44 pm
content: Equipment to convert computer signal to CRT was plentiful in the 1970's and 1980's... Resolution for typical (USA) TV was below 640 horizontal, most were in the 340 range. For 80x16 (80characters x 16 lines = 640x160), one would need to purchase a computer CRT back then.But today, it is cheaper and more functional if you purchase a new small LCD flat screenfrom Walmart (<$100USD) and convert that CRT TV to an LCD stand to hold up the new LCD, or as foot-rest to increase sitting comfort.I've a better CRT-TV sitting in the basement that I don't know what to do with. Too heavy for me to take to the township electronics dump, but so heavy it cost quite a bit to hire someone to do it for me. It is so heavy I just need G to drift up a bit and that thing would become a black hole with it's own mass. I am waiting still.Edit: Removed extra line breaks