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Old 01-12-2014, 03:22 PM
wa2ise's Avatar
wa2ise wa2ise is offline
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Looks like it was built for AM sound. If so, and if you get it restored and working, you could customize an RF modulator to produce AM modulated sound instead of FM. Most RF modulator chips have a separate video modulator and FM sound modulator. You'd need to provide a trap in the video signal to remove energy at 4.5MHz, so it doesn't contaminate the spectrum where the AM sound will be found once the video is modulated onto the RF video carrier. And you'd need to build an AM modulator at the sound carrier frequency.
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Old 01-12-2014, 05:05 PM
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Dave S Dave S is offline
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Quote:
Originally Posted by wa2ise View Post
Looks like it was built for AM sound. If so, and if you get it restored and working, you could customize an RF modulator to produce AM modulated sound instead of FM. Most RF modulator chips have a separate video modulator and FM sound modulator. You'd need to provide a trap in the video signal to remove energy at 4.5MHz, so it doesn't contaminate the spectrum where the AM sound will be found once the video is modulated onto the RF video carrier. And you'd need to build an AM modulator at the sound carrier frequency.
WA2ISE: that would probably be beyond my "shade-tree engineer" capabilities, although I'm certain all of you guys could and would talk me through such a project.

I'm currently discussing the merits of restoring such a set vs. just leaving it in original condition with a fellow collector. I wonder if anyone wants to jump in on that discussion? Maybe it would be appropriate to start a new thread for that.

-- Dave
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Old 01-13-2014, 05:39 AM
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cwmoser cwmoser is offline
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Quote:
Originally Posted by Dave S View Post
WA2ISE: that would probably be beyond my "shade-tree engineer" capabilities, although I'm certain all of you guys could and would talk me through such a project.

I'm currently discussing the merits of restoring such a set vs. just leaving it in original condition with a fellow collector. I wonder if anyone wants to jump in on that discussion? Maybe it would be appropriate to start a new thread for that.

-- Dave
Dave, when you do start your restoration, start a thread and post your
pictures, thoughts, and progress. I think a lot of us would like to follow
with you when you do the restoration.

Carl
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