Can you convert HDMI to coaxial cable?

I upgraded my cable/DVR and they gave me a main box and a set top box for my old second TV. However, I didn’t have the storage I was promised.They said that they would upgrade and I switched to a new DVD box. However, when I got it home I found it only had HDMI and component outputs. Verizon suggested buying a new TV but I see on Amazon that there are HDMI to coaxial and component to coaxial converters. Is this something that might work? I don’t need HDTV on this set. I really just want the extra storage for recorded programs because they told me I couldn’t use an e-SATA with this box, although it does have a slot marked e-SATA. If this is something a converter would work with then I would try it. Otherwise,I will need to either buy a new TV or downgrade to a lower level box.

If your TV only has coax you’ll probably need an RF modulator.

Is it worth buying such a thing ?
You may well buy a cheap new tv.

You can get a tv for $10? :dubious:

I see various prices for these. Most convert component to coaxial. Will this work? Do I need one of the hundred dollar ones or will a 10-20 dollar one do OK?

I was in Costco and they had Samsung & Vizio (decent brands) 32" TVs for $200 or less. 24" for $150. IMO, a better purchase than a converter for an obsolete TV.

If you need coax, you need Channel 3 (RF modulator) This would take composite (yellow RCA plug, where output is yellow composite, red and white Left-right audio) and produce analog old Channel 3 (or 4 or whatever) modulated with the composite signal. Composite is the signal that is sent over radio. Of course, if the modulator does not have audio in too (most don’t) then you have to produce the sound separately - either your TV also has audio in, or more likely, through a separate stereo amp. Classic RF modulators were to put video game output (really really old videogames) or VHS tapes onto a TV that did not have the composite in. Electronically, they are very simple.

Component (as in, RCA jack red, green, blue) is separate analog signals for each colour. Again, no sound. (it will be separate red-white) This is a bit trickier to convert to Channel 3 - as it needs to be converted to composite first. It’s electronically similar to the blue VGA computer screen output. The converters are a bit more expensive.

Finally, there’s HDMI - electronically similar to the big white DVI plug on newer computer monitors. The signal is strictly digital. This means to get composite, it has to be electronically converted to analog composite - a much more complex function.

The problem too, is there are so few “no composite” TV’s out there, still working, so no real demand for Channel 3 modulators. The cost of flat screens is so cheap (and they are so superior) that you may as well get a new TV, rather than buy expensive electronics that is only useful for an obsolete analog RF-only tube TV. (The biggest tube TVs were monsters at 35 inches. A 35-inch flat screen is tiny - and cheap!)

We had an expression where I used to work about throwing good money after bad, “jeweling the turd” where you spend so much money fancying up your POS that it just makes it that much harder to flush the toilet.

The Gefen HDMI to Composite S Video Scaler looks like it will do the trick.

I see it on Amazon for $278.75

No it won’t.

The only video output is composite or S-video. You would still have to take the composite output and run it into an RF modulator.

The coax output on that box is for S/PDIF audio.

A cheaper solution would be to run the component output into one of these and then to run the output of that into the modulator linked to earlier. I don’t know how much signal degradation would come from multiple conversions.

But then it does not produce Channel 3 (real Coax) so if the TV needs an RF signal, he’ll have to add a in an RF modulator in the chain.

To me, Coax means the coaxial black cable TV feed cable, with screw ends, not RCA jack unmodulated composite.

I guess the question is, which does the OP have?

Your TV doesn’t at least have component inputs??

The word coax is dreadful. Apart from HDMI (which uses twisted pairs) all of the different signal connection standards here are sent over coax. Component, composite, RF modulated, s-video. All coax inside. You can’t even tell from the connectors, because there is more than one connector for each signal type, although for domestic systems it tends to come down to RCA and either Belling-Lee or F.

So, for the OP. You need to be clear about what it is you mean. This affects the price, and even the legality (and thus obtainability) of the solution.

HDMI is able to provide video signals with a bewildering array of resolutions. But for the most part what matters is the brekpoint between SD (standard definition - what you get off a DVD, video tape, or old style free-to-air TV) and HD (high definition, what you get off a Blue Ray, HD digital TV, etc. HD starts at 720p in general, and is now commonly around at 1080i and 1080p.)

Where this is important is that if the content is copy protected (which from any commercial source it will be) the HDMI licensing prohibits any device from providing anything better than SD resolution as a raw video signal. So a HDMI to component converter that feeds 1080p output is not allowed. But one that outputs 480p is OK. Even a device that upscales SD content to HD is not allowed to provide a video output.

A HDMI to component converter is OK, as composite video can only support SD resolution.

A HDMI to component converter will produce a better picture than one that outputs to composite, even at SD, because it has more bandwidth to use. If your TV can accept composite, it is a better answer.

If your TV has no inputs other than an antenna connector (ie F or Belling-Lee) the resolution is even more messed up, and you will only get 480i. If this is all the box you have will provide, it really doesn’t matter. But it won’t be a great picture compared to what people are used to now. You will feel stuck in the last century. To use an antenna connection you need a modulator, and these use composite video as input.

Everything really depends upon the TV’s capabilities. If it is an old standard definition set, with no inputs other than an antenna you may want to seriously consider if you want to persevere with it. Even a basic high definition TV is quite cheap now. But if all you do is watch shopping channels, it probably won’t concern you.

I wrote

obviously should be
A HDMI to composite converter is OK, as composite video can only support SD resolution.

Also, component video at SD only is also legal, and produces the best picture.

OP, what model cable box is it if you don’t mind me asking? Because the trend in set top boxes has absolutely been the other way in outputs - HDMI for HD, and composite output (yellow for video, red & white for Audio) for SD, and eliminating component completely. There’s a very narrow segment of TVs that have component and don’t have HDMI, mostly around 10 years old, so the component output is an unneccessary expense.

Are you sure you’re not mixing up component and composite? Component - 5 connectors, green, blue, red for video, red and white for audio, Composite - 3 connectors yellow for video, red and white for audio.

To clarify, my TV has only one coaxial input. That is all. I do not want to buy a new TV at this time. This one has a built in VCR which I use to watch my old tapes.

This is the box. It has HDMI. component and composite outputs. To connect to a SD TV they recommend using the composite output which has the one video and the two audio plugs (yellow, red and white) which apparently lets you not have to use the separate three color component outputs.

This is the converter I am considering. To convert from HDMI requires 2 steps, converting from HDMI to composite and the from composite to coaxial input. I already have the cables for the composite and as noted the instruction book for the box states that I can use the composite (yellow/white/red) to connect to an older TV so I am thinking that this converter will then let me use the coaxial input on my TV.

Both your links point to the set top box page, so I can’t see the converter you’re suggesting. But the VMS1100 does have a composite output, so all you need is a composite to RF modulator, like Doug K linked to in post 2 - Amazon.com. There’s no reason to use the component or HDMI outputs at all.

Sorry-did not double check the link.
This is the converter.

And if I but a new TV and want to watch my old VHS tapes that means purchasing a new VHS player (if they even exist) and then hooking that up to the TV in addition to the cable box. That is even more of a headache.

I guess I cross-posted but it seems like I am on the right track. As long as I am not doing anything illegal or dangerous it seems like it is a cheap fix to try that. As noted, I already have the cables, since my other TV (the good one) came with a full set of options for hook-up.

Yes, that will work. Here’s the same thing cheaper on amazon. (which I swear was the link I first posted).

And yep, if you want to watch VHS tapes you’ll have to buy a new player, (which will probably come as a DVD/VCR combo) and hook it up too.

ETA: Why am I seeing Doug K, my, and psychobunny’s links to the modulator sometimes go to Walmart, sometimes to amazon? Is it my browser or some crazy bot on the board replacing links to products?

This is weird. I swear when I checked the link in post #2 last night it sent me to a different item at Walmart. Now when I check Amazon, it says I already bought this item yesterday but it is still in my cart. In any case, it seems that at least 2 people here think that this particular converter may work for me and since I apparently ordered it in my sleep I’ll just wait and see if it works. Thanks all for the aid. As you can see I am very slowly and cautiously venturing into the technology of the 21st century. I’ll get there eventually. I have a smart phone and everything!