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anikom15
Instigator/Local CRT Guru
Reged: 04/11/16
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Re: Finding real technical information of LaserDisc is hard work.
06/26/17 03:26 AM


Let me be clear, I'm assuming the anti-aliasing filters are sufficient to get a good digital signal conversion, and that the filter is used before resampling down to 28.4 MHz for storage.

The harmonics don't contain information and thus we only need to sample at the highest frequency deviation for the FM signal. A good ADC will reduce aliasing from the harmonics. Clipping is a normal stage in FM systems. In this case it's just done at the transmitter stage instead of at the receiver.

If we want to preserve the disc signal itself (i.e. the pulses), and not just the composite signal, we'd want to sample at at least twice the bandwidth of the optical detector.

I've heard that the SNR is around 50 dB for video and 110 dB for audio. This is regarding the demodulated signals however. For FM, we will only need 1 bit per signals. The dynamic range is only dependent on the frequency deviation.

With all this said we have some choices:

1) Store the PWM signal
This is the most similar to how the disc is stored. It requires a lot of bandwidth, and the emulator has to demodulate everything.

2) Store the FM signal
This is essentially the same as above but I don't think it can easily recreate the original medium. It requires less bandwidth though.

3) Store the streams
This demodulates the audio and video but doesn't process the video signal. The emulator has to do it.

4) Capture the video
This demodulates everything and also converts the video to some lossless format. You also have to define a format for v-blank data.







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* Question about ALG driver status DarkMoe 06/22/17 10:47 PM
. * Re: Question about ALG driver status TrevEB  06/26/17 08:20 AM
. * Re: Question about ALG driver status Haze  06/28/17 02:13 PM
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. * Re: Question about ALG driver status casm  07/19/17 03:31 PM
. * Re: Question about ALG driver status smf  07/22/17 07:47 AM
. * Re: Question about ALG driver status anikom15  07/22/17 08:23 AM
. * Re: Question about ALG driver status casm  07/22/17 05:40 PM
. * Re: Question about ALG driver status anikom15  07/22/17 06:07 PM
. * Re: Question about ALG driver status smf  08/06/17 02:55 PM
. * Re: Question about ALG driver status uman  07/22/17 06:31 PM
. * Re: Question about ALG driver status DarkMoe  08/01/17 04:23 PM
. * Re: Question about ALG driver status StilettoAdministrator  07/19/17 06:07 PM
. * Re: Question about ALG driver status Vas Crabb  07/19/17 06:10 PM
. * Re: Question about ALG driver status Pernod  07/19/17 07:15 PM
. * Re: Question about ALG driver status StilettoAdministrator  07/19/17 07:50 PM
. * Re: Question about ALG driver status Pernod  07/19/17 09:11 PM
. * Re: Question about ALG driver status casm  07/19/17 08:45 PM
. * Re: Question about ALG driver status StilettoAdministrator  07/19/17 06:36 PM
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. * Re: Question about ALG driver status casm  07/20/17 03:14 PM
. * Re: Question about ALG driver status anikom15  07/15/17 08:56 PM
. * Re: Question about ALG driver status uman  07/15/17 09:34 PM
. * Re: Question about ALG driver status anikom15  07/18/17 07:41 AM
. * Re: Question about ALG driver status smf  07/17/17 08:30 AM
. * Re: Question about ALG driver status uman  07/17/17 01:46 PM
. * Re: Question about ALG driver status smf  07/18/17 10:48 PM
. * Re: Question about ALG driver status anikom15  07/19/17 04:31 AM
. * Re: Question about ALG driver status casm  07/17/17 04:16 PM
. * Re: Question about ALG driver status uman  07/17/17 06:11 PM
. * Re: Question about ALG driver status casm  07/19/17 04:08 PM
. * Re: Question about ALG driver status Rygar9  07/18/17 01:57 AM
. * Re: Question about ALG driver status uman  07/18/17 12:23 PM
. * Re: Question about ALG driver status SmitdoggAdministrator  07/18/17 07:36 PM
. * Re: Question about ALG driver status uman  07/18/17 11:08 PM
. * Re: Question about ALG driver status anikom15  07/19/17 05:09 AM
. * Re: Question about ALG driver status casm  07/19/17 04:22 PM
. * Re: Question about ALG driver status Vas Crabb  07/19/17 04:33 PM
. * Re: Question about ALG driver status Rygar9  07/20/17 12:21 AM
. * Re: Question about ALG driver status R. Belmont  07/20/17 08:54 PM
. * Re: Question about ALG driver status anikom15  07/20/17 04:02 AM
. * Re: Question about ALG driver status redk9258  07/20/17 01:12 AM
. * Re: Question about ALG driver status StilettoAdministrator  07/19/17 05:53 PM
. * Re: Question about ALG driver status casm  07/19/17 08:12 PM
. * Re: Question about ALG driver status uman  07/20/17 11:56 AM
. * Re: Question about ALG driver status anikom15  07/20/17 08:45 PM
. * Re: Question about ALG driver status casm  07/20/17 04:02 PM
. * Re: Question about ALG driver status uman  07/20/17 05:21 PM
. * Re: Question about ALG driver status casm  07/21/17 12:44 AM
. * Re: Question about ALG driver status anikom15  07/20/17 09:06 PM
. * Re: Question about ALG driver status uman  07/20/17 11:05 PM
. * Re: Question about ALG driver status anikom15  07/21/17 02:15 AM
. * Re: Question about ALG driver status uman  07/21/17 10:15 AM
. * Re: Question about ALG driver status anikom15  07/22/17 04:18 AM
. * Re: Question about ALG driver status uman  07/22/17 01:17 PM
. * Re: Question about ALG driver status MooglyGuy  07/22/17 10:15 AM
. * Re: Question about ALG driver status uman  07/19/17 07:30 PM
. * Re: Question about ALG driver status anikom15  07/19/17 08:24 PM
. * Re: Question about ALG driver status uman  07/19/17 10:05 PM
. * Re: Question about ALG driver status anikom15  07/20/17 04:06 AM
. * Re: Question about ALG driver status casm  07/19/17 04:44 PM
. * Re: Question about ALG driver status SmitdoggAdministrator  07/18/17 11:17 PM
. * Re: Question about ALG driver status uman  07/19/17 12:29 AM
. * Re: Question about ALG driver status casm  07/19/17 04:36 PM
. * Re: Question about ALG driver status SmitdoggAdministrator  07/19/17 12:38 AM
. * Re: Question about ALG driver status uman  07/19/17 01:45 AM
. * Re: Question about ALG driver status anikom15  07/18/17 08:03 AM
. * Re: Question about ALG driver status Vas Crabb  07/18/17 08:24 AM
. * Re: Question about ALG driver status anikom15  07/19/17 04:27 AM
. * Re: Question about ALG driver status uman  06/28/17 04:52 PM
. * Re: Question about ALG driver status SmitdoggAdministrator  06/23/17 06:13 PM
. * Finding real technical information of LaserDisc is hard work. taz-nz  06/25/17 08:17 AM
. * Re: Finding real technical information of LaserDisc is hard work. Olivier Galibert  06/25/17 11:37 AM
. * Re: Finding real technical information of LaserDisc is hard work. anikom15  06/25/17 06:19 PM
. * Re: Finding real technical information of LaserDisc is hard work. Olivier Galibert  06/25/17 11:15 PM
. * Re: Finding real technical information of LaserDisc is hard work. anikom15  06/26/17 12:44 AM
. * Re: Finding real technical information of LaserDisc is hard work. Vas Crabb  06/26/17 01:41 AM
. * Re: Finding real technical information of LaserDisc is hard work. anikom15  06/26/17 03:26 AM
. * Re: Finding real technical information of LaserDisc is hard work. taz-nz  06/26/17 12:48 PM
. * Re: Finding real technical information of LaserDisc is hard work. uman  06/26/17 01:11 PM
. * So are you volunteering to do the hardware side of things? MooglyGuy  06/26/17 11:40 AM
. * Re: So are you volunteering to do the hardware side of things? anikom15  06/26/17 11:50 AM
. * Re: So are you volunteering to do the hardware side of things? taz-nz  06/26/17 01:15 PM
. * Re: Finding real technical information of LaserDisc is hard work. Vas Crabb  06/26/17 07:52 AM
. * Re: Finding real technical information of LaserDisc is hard work. anikom15  06/26/17 11:47 AM
. * Re: Finding real technical information of LaserDisc is hard work. taz-nz  06/25/17 12:41 PM
. * Re: Finding real technical information of LaserDisc is hard work. CTOJAH  06/25/17 12:45 PM
. * Re: Finding real technical information of LaserDisc is hard work. anikom15  06/25/17 06:40 PM
. * Re: Question about ALG driver status DarkMoe  06/23/17 06:16 PM
. * Re: Question about ALG driver status SmitdoggAdministrator  06/23/17 06:19 PM
. * Re: Question about ALG driver status DarkMoe  06/23/17 06:23 PM
. * Re: Question about ALG driver status SmitdoggAdministrator  06/23/17 06:28 PM
. * Re: Question about ALG driver status uman  06/23/17 08:12 PM
. * Re: Question about ALG driver status R. Belmont  06/23/17 10:12 PM
. * Re: Question about ALG driver status casm  06/25/17 05:25 PM
. * Re: Question about ALG driver status uman  06/25/17 10:07 PM
. * Re: Question about ALG driver status casm  06/26/17 02:12 AM
. * Re: Question about ALG driver status anikom15  06/25/17 06:48 PM
. * Re: Question about ALG driver status casm  06/26/17 02:16 AM
. * Re: Question about ALG driver status uman  06/26/17 12:43 PM
. * Re: Question about ALG driver status casm  06/27/17 12:40 AM
. * Re: Question about ALG driver status anikom15  06/26/17 03:41 AM
. * Re: Question about ALG driver status uman  06/24/17 01:50 PM
. * Re: Question about ALG driver status Sune  06/24/17 07:53 PM
. * Re: Question about ALG driver status uman  06/24/17 09:22 PM
. * Re: Question about ALG driver status SmitdoggAdministrator  06/23/17 08:22 PM
. * Re: Question about ALG driver status DarkMoe  06/23/17 07:01 PM
. * Re: Question about ALG driver status CTOJAH  06/22/17 11:39 PM
. * Re: Question about ALG driver status uman  06/23/17 11:45 AM
. * Re: Question about ALG driver status smf  06/23/17 04:56 PM
. * Re: Question about ALG driver status CTOJAH  06/23/17 05:44 PM
. * Re: Question about ALG driver status smf  06/23/17 05:57 PM
. * Re: Question about ALG driver status R. Belmont  06/23/17 10:35 PM
. * Re: Question about ALG driver status DarkMoe  06/23/17 06:14 PM
. * Re: Question about ALG driver status SmitdoggAdministrator  06/23/17 06:16 PM
. * Re: Question about ALG driver status DarkMoe  06/22/17 11:42 PM

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