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dozley
23-03-2006, 09:47 AM
I'm aware that as it stands there is no way for US Series 1 tivo (PAL modded) to decode NICAM stereo in NZ via a FTA PAL tuner. Hopefully work is still ongoing, but I understand it may be a "dead duck".

Which leads me onto my next thought...
My understanding is that the NICAM signal is sent as part of the RF signal which goes into the Tivo. At present the Tivo has no way of decoding the stereo, but...is it in any way possible to "pass through" the NICAM signal so it can be decoded by a Nicam equipped television?

Cheers,

Dorian

Darren King
23-03-2006, 11:18 AM
Hi Dorian

Yes. The PAL tuner module is a direct RF in/RF out device for all things not related to the TiVo signal, but note it is a powered passthrough so you need to have the TiVo on to get signal passed from RF in to RF out.

So daisy chaining the TiVo in the middle will not affect the decoding of NICAM on your TV for all non-TiVo channel reception.

thomson
23-03-2006, 12:11 PM
I'm aware that as it stands there is no way for US Series 1 tivo (PAL modded) to decode NICAM stereo in NZ via a FTA PAL tuner.

In the short term your best approach would be using a Nicam decoder board. See this thread (http://www.forums.oztivo.net/showthread.php?t=357).

dozley
23-03-2006, 12:51 PM
Thanks for the quick reply guys.

I understand the PAL tuner pass through works - that's good to hear.
So, the Tivo receives the RF signal, records it in mono, and outputs it in mono.
Is there no way for the Tivo to output an "undecoded" NICAM signal (the same as it receives), for later decoding by the Nicam equipped TV?

Cheers,

Dorian

Darren King
23-03-2006, 01:04 PM
To do that it would need to first encode the NICAM into the digital stream that gets passed to the hard disk. TiVo's constantly record to the hard disk be it actually "recording" as you know it, or watching live TV so it can maintain the 30-minute replay buffer.

And therein lies the root problem. If you could do that then problem solved! But for this to happen requires the Micronas chip to be configured for NICAM support which at this point in time is not possible - apart from adding the decoder board that Thompson mentions which I don't think anyone has yet.

thomson
23-03-2006, 01:21 PM
All we need is a small circuit that takes a 38.9MHz SIF signal, decodes the 5.5/5.85MHz NICAM stereo signal and outputs left/right audio. Unfortunately finding a Nicam decoder chip is not so easy...

It might be easier to purchase an old Nicam VCR and rip it apart, find the datasheet for its decoder chip and start from there.

dozley
23-03-2006, 01:32 PM
So if the NICAM is decoded PRIOR to the Tivo (ie via a STB or NICAM video), then the Tivo can encode it as part of the digital stream and then output it to the television.
If the NICAM is not decoded prior, there is no way for the NICAM portion (encoded) to be included in the digital stream, and output for decoding at a later date (by the television or some other device).

I guess if I want Nicam for the bedroom, then next best option would be for me to purchase a UK Tivo...

Thanks for clarifying the situation,

Dorian

Darren King
23-03-2006, 02:19 PM
Yes. If you use an external decoder (ie a set top box or a VCR) that decodes the sound into analogue line level left/right audio then you simply feed this into the rear A/V input on the TiVo and the video into either the RCA or S-Video socket.

dozley
23-03-2006, 09:32 PM
The other way I could do it to watch specific programs in stereo in the bedroom, would be to record the program in the lounge via my STB (in stereo), and then by using MFS-FTP I could copy it across to the Tivo in the bedroom.
I'll have to download the MFS-FTP package and patch and give it a whirl...

Dorian