Odd Laserdisc Question

Discussion in 'Archived Threads 2001-2004' started by Vince Maskeeper, May 10, 2002.

  1. Vince Maskeeper

    Vince Maskeeper Producer

    Jan 18, 1999
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    I've owned a number of players throughout the years, but have never gotten around to trying this... Also, I don't know as I ahve ever seen it mentioned before, so I wondered if any laserdiscers had ever done it...

    Since AC-3 is modulated and carried on one of the analog channels (the right one I think)-- I've always assumed the modification kits availble to add AC-3 output to a LD player simply tapped into the analog stream for the channel that contained DD AC3, and added a jack for it to be spit out on.

    So, I wondered if anyone ever just hooked up the right analog otput from the player into a demodulator? I would assume that if the analog output had the bandwidth equal to the modulated signal, that there would be no reason it wouldn't pass just fine.

    Again- seems like a silly question- I'm sure that it is common knowlegde why it does/doesn't work-- but since I missed the heyday of Laser and have never seen it mentioned, I just wondered.

  2. Michael Reuben

    Michael Reuben Studio Mogul

    Feb 12, 1998
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    I can't give you the technical reasons, but I know it doesn't work. There's some sort of processing applied to the analog signal before it reaches the output; the signal has to be tapped before that processing in order to get the RF-modulated AC-3.

    I'm sure Rachael will know.

  3. Rachael B

    Rachael B Producer

    Jun 5, 2000
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    Knocksville, TN
    Real Name:
    Rachael Bellomy
    Vince, the right analog was the one that was used to feed the RF line out of LD players that had RF outs. I'm not talking about AC-3 RF out, I'm talking about the older players that had an RF output. I have an early 80's Magnavox toploader that has an RF in and out. The first player I bought was the LD-838D in 1987. By that time they had forgotten the RF pass-thru but the 838 gave you the option of using composite video or it's RF output.

    In '95 I saw advertised in Stereo Review a box to use the RF output of so-equiped players to get the AC-3 RF out that'a way. I can't remember who made it but I do remember it cost $450, which seemed ridiculous to me since you could buy one of the cheaper AC-3 equiped player for those clams. That's the only other way to get AC-3 RF that I know of besides the regular way. Best wishes!

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