HDMI Modulator RF Converter RCA Coaxial Composite VHF UHF SDR Demodulator Adapter w/Antenna in/Out & Channel Switch for Roku Fire Stick Cable Box HD Digital AV Component Video to Analog NTSC Coax TV

Added: Have been using for well over two years and still working perfectly.This product puts out a very good and clear picture when connected straight to a TV set. The modulator is hard to setup and the instructions are not clear. One review I read said you have to figure out how to set it up before you can understand the instructions. I think that is very accurate however I haven't figured out the instructions and I have it set up. I was able to make it work but not on the channel I wished to use. (eventually I think I'll get it).My home has a commercial modulator system with 16 channels in one location. I needed one more channel and decided to try this box because the commercial box would require a great deal of money. I would have to purchase another 16 unit system and install only one channel. So I decided to give this modulator a try.When I wired my home I had all TV cable wires terminate into one large closet. From there I can play a DVD or satellite or any other device and it feeds through my commercial modulator to a specific channel and then it distributes throughout the house. In this way if I am watching a DVD or a FireTV I can see it on every TV in the house at the same time by just tuning the TV to that channel.After many attempts to add this onto my system in different configurations I came up with a way to get this modulator to work. The modulator just does not have the power to modulate to more than one TV. By simply adding a 24db Distribution Amplifier which I purchased from Amazon I was able to make it work. ( I installed a smaller cheaper one which I also purchased from Amazon and it did NOT do the trick).I simply install the 24db Distribution Amplifier to the coax cable output on the modulator and then run the coax cable output on the amplifier to my system and SUCCESS! I can now see the picture as clear on the channel with this less expensive modulator as I can on my commercial modulated channels.For the money you can't beat it.Both my commercial modulator and this one are all analog but they work well (wish they would come up with a digital one at this price I would replace my whole system).Hope this helps!

This works well but will not add in audio from RCA jacks when using HDMI.Also this device stopped working 3 months after I started using it and I can not get it repaired or replaced!

Setup was a little technical as a couple of reviews said, but the unit works well. basically make sure you have the NTSC unit in the US, Google the transmit frequency for the TV Channel you want, select the group an number from the chart on the included docs. Tune your TV to that station and adjust the fine tune knob to get a clear picture.

TLDR: This is a good box, the signal is excellent quality, the documentation is a little obtuse, and there are technical issues that might affect your installation.Details: The box works just fine...mostly. I could replicate the audio problem (static on the audio signal), and it seems that some of the channels, but not all, will sound scratchy if you tune the TV first, and then tune the box to match. changing the channel on my TV to a different channel, and then coming back to the desired channel cleared the problem for me, but your mileage may vary.The documentation isn't super user friendly, but here's a fast version: The mode button changes the "band", so if you select 'n0', you can change to channels 2-6, plus 95-99. Want channel 45? Then you have to select the 'n3' band first, then you can access that particular channel. It's reminiscent of having to push that big UHF/VHF button on TV's in the 70's. Also to clarify: this box does NTSC only, so if you want PAL, you gotta buy the PAL version of this box. You can also ignore all the PAL instructions in the booklet!The signal output was excellent. I tested using an RCA connection to an old VCR, and the signal was clean for all channels but number 2, which had some moderate snow in my case. That said, at least on my box, channels 7-22 were mapped incorrectly. Channel 7 on my box output the frequency for channel 16, 8 for 17, and so on. If you hunt around on your TV (or you have a UHF frequency table to compare to the instruction booklet), you can find the signal parked on another channel nearby. It's a minor annoyance, but if your project needs a signal on one of those channels, you may have to do some experimenting. In defense of the product, it *does* have all the frequencies, and they all *do* work...just not in the right order!So, super good box for the price; I'd buy another one. Just be aware it isn't perfect.

Quality is ok, not the best, but the biggest issue is that when the modulator is set to channel 5, the video is actually showing up on channel 7. All of the channels on my unit are offset 2-3 left or right. I tried on another TV and had the same problem. It works, but you need to adjust some things to get a good picture.

I used this to connect a fire stick via HDMI to a dinky little CRT television with only a coaxial input. After a few minutes of messing with the buttons, I got a perfect picture and sound. It does not require an external digital tuner for the television. This unit works with both PAL and NTSC frequencies so if it isn't working right make sure you switch to the correct region. The unit arrived set on PAL and I was getting a distorted picture and loud hissing. After realizing I had to switch to NTSC it started working great. HDMI and composite in both work flawlessly.Build quality is not great, the recessed knobs to alter brightness and volume were a bit crooked and difficult to manipulate with a screwdriver and the metal body is quite thin. I don't know if it would survive a fall onto a hard surface. However the only competition at this price range for HDMI to coax is the RadioShack rf modulator which has significantly less features than this one does. I'm leaving 5 stars because there is really nothing comparable on the market at this price.