Last night I had an idea. Certain DTV converter boxes, like the one made by thomson/RCA actually have physical channel buttons on the front of the box.
http://jonsey.blogdns.org/img/dta800.jpg
Say you had a Zenith with space command or some other set with an ultrasonic remote and receiver. Would it be possible to modify the DTV box so that the space command receiver could actuate the channel change on the box? My idea is to replace the momentary switches on the DTV box with relays, disconnect the tuner motor from the space command reciever, and connect it to the relays. That way, the channel function on a vintage remote set would still work after the 2009 analog cutoff, and a vintage daily watcher could retain full remote functionality. If there was enough space inside the cabinet, the DTV box could even be hidden, though some shielding may be necessary. Any thoughts, comments?

Yes, I am sure you could do this. In fact, it could be fun to use an old remote control with a DTV box and a non-remote-control old set.

Rather than pull parts from an old set, how about using an ultrasonic transducer as a microphone, connected to a circuit with two LM567 (I think) tone-decoder chips tuned to the frequencies from the Space Command remote control? You might start by connecting such a transducer with an ultrasonic-capable preamp to an oscilloscope to learn the frequencies, then build the 567 circuits using a signal generator for test input.

Yes, I am sure you could do this. In fact, it could be fun to use an old remote control with a DTV box and a non-remote-control old set.

Rather than pull parts from an old set, how about using an ultrasonic transducer as a microphone, connected to a circuit with two LM567 (I think) tone-decoder chips tuned to the frequencies from the Space Command remote control? You might start by connecting such a transducer with an ultrasonic-capable preamp to an oscilloscope to learn the frequencies, then build the 567 circuits using a signal generator for test input.
That's a great Idea too. Maybe build the entire thing into the cabinet from an old UHF converter.:scratch2:
My original idea was to retrofit a set so that you could never tell the DTV box was inside, and make the modification completely reversible so that the set could be returned to original condition by simply reconnecting the tuner drive motor.

wow that is a great idea! I have a color 1967 magnavox with ultrasonic remote, and I was really sad when I bought the converter box and the remote because unecessary =( if you could make something like that, I would totally buy one from u =)

Bob and I were discussing things like this last week. He had a good idea, another way to still use a remote set is: take 5 converter boxes, 5 commercial RF modulators from like a hotel or something {look on the bay} set on 5 different channels {VHF}, skipping every other one to eliminate bleed over. Then find 5 of your favorite channels on the boxes, one on each box. Then, hook all this up to a video combiner to get it all into one coaxial wire, this can then be routed to every room in the house if you want. Lastly, hook your remote set to the coaxial and enjoy 5 crystal clear channels on your mechanical ANALOG tuner with no mods to any set. My idea was similar to fsjonsey's, I wanted to take apart a box, mount it inside an old set {NOT an early color set} maybe like a mid '60s B/W console. Take the IR sensor and move it to a location on the front of the set hidden from view and hook the box to the incoming power supply. Then, hook the coax to the set internally and hook the ant. input from the box to the terminals on the back of the set, hook up the amplified ant. and enjoy remote controlled B/W. OR jack the thing into the chassis to the first I.F. and bypass the tuner altogether. But I thought maybe that would make it harder to hook other things to the set when done that way, i.e. DVD, VCR ect. It is also crappy that there is no pass through so maybe run an extra coaxial outside the set to hook up the other components. Any suggestions on improvements on the idea are welcome.

If you wanted, you could get 7 VHF channels squeezed in there instead of 5... remember channels 6 and 7 are not adjacent to each other (the FM band is in between them) - so for a channel scheme, you could do 2,4,6,7,9,11,13. Also you may want to investigate adding bandpass filters to the output of each modulator, as you may have some trouble with harmonics.

Bob and I were discussing things like this last week. He had a good idea, another way to still use a remote set is: take 5 converter boxes, 5 commercial RF modulators from like a hotel or something {look on the bay} set on 5 different channels {VHF}, skipping every other one to eliminate bleed over. Then find 5 of your favorite channels on the boxes, one on each box. Then, hook all this up to a video combiner to get it all into one coaxial wire, this can then be routed to every room in the house if you want. Lastly, hook your remote set to the coaxial and enjoy 5 crystal clear channels on your mechanical ANALOG tuner with no mods to any set. My idea was similar to fsjonsey's, I wanted to take apart a box, mount it inside an old set {NOT an early color set} maybe like a mid '60s B/W console. Take the IR sensor and move it to a location on the front of the set hidden from view and hook the box to the incoming power supply. Then, hook the coax to the set internally and hook the ant. input from the box to the terminals on the back of the set, hook up the amplified ant. and enjoy remote controlled B/W. OR jack the thing into the chassis to the first I.F. and bypass the tuner altogether. But I thought maybe that would make it harder to hook other things to the set when done that way, i.e. DVD, VCR ect. It is also crappy that there is no pass through so maybe run an extra coaxial outside the set to hook up the other components. Any suggestions on improvements on the idea are welcome.

Nice! Thanks for the input!

My idea was similar to fsjonsey's, I wanted to take apart a box, mount it inside an old set {NOT an early color set} maybe like a mid '60s B/W console. Take the IR sensor and move it to a location on the front of the set hidden from view and hook the box to the incoming power supply. Then, hook the coax to the set internally and hook the ant. input from the box to the terminals on the back of the set, hook up the amplified ant. and enjoy remote controlled B/W. OR jack the thing into the chassis to the first I.F. and bypass the tuner altogether. But I thought maybe that would make it harder to hook other things to the set when done that way, i.e. DVD, VCR ect. It is also crappy that there is no pass through so maybe run an extra coaxial outside the set to hook up the other components. Any suggestions on improvements on the idea are welcome.

I have thought about adding the DTV Tuner to an older set. The DTV Tuner has some benefits like adding remote to TVs without & adding features to one like my 75 Zenith Chromacolor II w/ Space Command which cycles through the volume including turning TV off. I would rather add component inputs so RCA cable inputs could be used instead of APT. The DTV Tuner boxes are small like a book & easily hidden esp. w/ long cables.

The DTV Tuner box could be set to Ch. 3 & the VCR to Ch.4 which would allow the use of the original remote to switch between them. As you know the DTV Tuner would need to go to the VCR first to record DTV after the Feb. changeover which could eliminate the need for APT (or else a second DTV Tuner for VCR).
For those needing APT:
My current info. is that the coming Zenith DTT901 w/ APT should be the best. A preliminary report on the currently available Microprose MPI-500PT with APT puts it near the Zenith (possible negligible difference if one wants a feature of the Microprose). MPI-500PT goes to APT with box "off" in Standby mode. In addition it looks like it could be modified to run on batteries easily.
http://www.microprosesystems.com/dtv.htm
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