I have a DVD/VHS player with RF output. Is there some way the DVD player digital output can be converted into an analog output ? I tried running the digital signal through a broadcast TV digital to analog converter box, but that didn't work. The DVD player works OK when connected to a digital TV.

Thanks - John

Maybe it would be good to just explain what you want to do and show us a picture of the back of your player. I'm suspecting you don't really want to convert a digital output to an analog output. I assume you are really just trying to play the DVDs or VHS tapes on a vintage television which should be pretty easy, but to tell you what to hook where might depend on how things are labelled.

Curtis Eickerman

Curtis: Thanks for responding. Yes, I really do want to convert a digital output to an analog output. My '49 Zenith portholes are analog only with RF cable input only. The DVD/VHS player has four cable outputs: RF, S, RCA, and composite. The DVD player's digital output, or the VHS player's analog output, is passed through all four of these cable outputs.

John

OK. You can consult your DVD/VHS manual, but I think you will find that the RF output is standard NTSC (plain old TV stuff). However, it is likely you have the standard 75 ohm F connector on the back of the DVD for connecting to a reasonably modern TV. On the 49 Zenith you are probably looking at 2 screw terminals that say antenna.

What you need is one of these: http://www.radioshack.com/product/index ... Id=2062049 plus a piece of 75 ohm TV coax with connectors. One end of the coax to your player and the other end screwed onto the 75 ohm to 300 ohm adapter. Then the terminals of the adapter connect to your TV. The DVD player will typically play on either VHF channel 3 or 4 (usually selectable in some way), so make sure the TV is on channel 3 or 4 to match.

It should work fine unless I am just completely misunderstanding something.

Curtis Eickerman

Curt's right on the money but here is another option.

Every time I'm in Goodwill or Savers, I look for RF modulators. They are little boxes that were made in the 90's or around then so you could play DVD players on TV's that didn't have inputs for them. I've bought a number of them and never paid over $4.00. A VCR will do the same thing but the modulators are much smaller and can be stashed behind or inside the set. If all you are going to play is DVD only, they are the ticket. You will need the same connectors and cable for either one.

Curtis, Greg: Problem solved. I have an RF modulator but didn't realize it converted digital to analog. Just to see what would happen, I connected RCA cables from the DVD/VHS player to the RF modulator and an RF cable from the modulator to the Predicta, turned every thing on, put in a disk, and it worked.

Thanks for your help - John

John-

If it works, ultimately you are all set, but I am surprised that you had to use the external modulator to get a DVD RF signal. None of that player's outputs are "digital", unless it has a coaxial or optical audio output, or if it has an HDMI output. All the ones you mentioned are analog even though the DVD carries digital data (that is converted to analog before it hits the jacks you mentioned). You did not mention component-video outputs (Y, Pr, Pb) which most DVD players have, but often if the analog outputs do not work it is because the DVD part of the machine is set to "progressive scan" mode. Turning that off in the menu (or sometimes with a front-panel button) would bring back the other outputs, but your player is the first combo one I have heard of where the RF output may not work for DVD playing.

There's analog video, and then there's RF modulated with analog video.

S-video, composite video, component video, RGB, etc. are all analog video. To get RF modulated with analog video, you do indeed need a modulator.

If you feed a signal into a TV at the tuner input, you need RF modulated with analog video. If you feed the signal in after the video detector (this requires custom wiring; no antique TVs have this input readily available on the back panel), you can use plain analog video.

As a side note, modulators do not convert digital to analog. They modulate RF with whatever signal you give them, which is generally intended to be analog. The reason you had success above is because you in fact used an analog video signal as an input to an RF modulator, which then produces RF modulated with analog video.

Chris and Tom: Thanks for the info. I removed the RF modulator and connected the player directly to the Predicta with an RF cable. It worked, the picture was even better but the sync buzz was a little louder, but its still hardly noticeable. The player I'm using is an older unit I bought at Goodwill, because I wanted one with RF input and output that I could dedicate to my older TVs. I tested it on a small LCD TV which has a dual tuner to make sure it worked and assumed, in error, that the DVD output was digital. The reason I assumed this was because the DVD/VCR player I have on my main LCD TV has HDMI output for the DVD and RCA cables for the VCR.

This will allow me to start watching some of the DVD movies I've recorded. I have Comcast and got one of their DTA converter boxes. When I hooked it up to the Predicta, the picture was terrible, and the sync buzz really loud. After several seconds, I shut it down because I was afraid the signal would damage the Predicta's electronics.

Again, thanks for the help - John

By the way, there are HDMI to analog converters out there like this one: http://www.amazon.com/HDMI-RCA-componen ... B002WBOQPU

I'm sure the day will come (if it hasn't already) when there will be DVD / Blu-Ray players that only have digital HDMI outputs.

It's a good time to grab up a few older VHS/DVD/cable-tuner combo's with the built in rf modulators.

You might want to look at ebay (uggh!) for what they call a Frequency Agile Modulator. This is what the cable companys use for
each channel. I picked one up for $35.00 and it will allow me to "broadcast" to TVs anything you can input to the thing. You can
use a DVD, camera, cable, or computer. You have the ability to select a vacant channel in your area and are limited to the two
channels (3 or 4) from the DVD boxes.

It also works great as a Amateur radio TV exciter for one of our UHF bands.

Clayton N4EV

This article describes how I use a Blonger-Tongue agile modulator to transmit TV within our house.

http://antiqueradio.org/HomeTVTransmitter.htm

Works well.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

It appears to me that the Amazon unit decodes the digital from HDMI to componant like R,G,B. To get that to a full color NTSC video signal you will need an encoder it and then a modulator to get it to RF for an analog TV.

Did you not say that your player had a analog RF output?

By the time you convert the digital back to NTSC analog it won't look any better.

An HDMI cable has something like 23 wires in it BTW.

Jim