Uhf modulator sound carrier problem

[len davis]

Hi Again,
Does anybody know if the modulator sound output of 6.0mhz can be changed to 5.5mhz in software.
This is the standard unit fitted to a UK Thompson Tivo


Thanks
Len

[zollymonsta]

Hi Again,
Does anybody know if the modulator sound output of 6.0mhz can be changed to 5.5mhz in software.
This is the standard unit fitted to a UK Thompson Tivo


Thanks
Len

Do you know what brand of modulator it has fitted in it?

If you find out and do a search on the web, you may find some technical documents on it. Possibly it has a pot on the side of the modulator that can be adjusted (though I'm not sure how you would set it to the correct frequency without the correct test equipment).

[len davis]

There is not a make on the tuner, I already did a search with the numbers, but no luck.
I used to adjust the output on imported videos in the Uk but this one is totaly different, there are no pots and no colis to adjust, I suspect that its done with ceramic filters or software adjusting from the clock ratio in an ic.
Len

[number6]

There is not a make on the tuner, I already did a search with the numbers, but no luck.
I used to adjust the output on imported videos in the Uk but this one is totaly different, there are no pots and no colis to adjust, I suspect that its done with ceramic filters or software adjusting from the clock ratio in an ic.
Len

It will be able to be done in software.

Whats needed is the documentation on the tuner module to find out what registers in the "RF output" part of the tuner module need to be controlled to select the Carrier frequency.

Someone must have had this sort of information to produce the UK Palmod software in the first place - and I've asked on oztivo for that information and no-one has put their hand up to say they had the info.

The reason why I know this will be software controlled is that the Tuner module in the UK TiVo is fully "world standard" - you can select which Audio/Video standards to decode and it does so. So given the RD input side is software controlled, the RF output side must similarly be software controlled.

Anyway, an alternative is to ask the guys with the Samsung Tuner modules how to control the output sound carrier frequency via software, and replace the Samsung Tuner module I2C address with the proper "Thomson" tuner module I2C address and then get the UK Palmod source code modified to allow you to select 5.5Mhz sound carrier on the Thomson tuners rather than the current "default" of 6.0.

Why the Samsung tuner module? Well its supposedly Pin for Pin compatible with the model of Tuner used in the UK Tivos. So, the registers are pretty compatible, only the I2C "addresses" are different for the modules in the tuner.

In my case, my [Panasonic] TV lets me specify the sound carrier for each TV channel, so I have set up a couple of TV channels on my TV with 6.0 Sound carrier and problem solved for m 2 UK TiVos.

I'd prefer to be using 5.5MHz but this is the workaround until then.

[johnh]

HI
The UK tuner is usually an ALPS TMDG2.
I bought a US tivo and got an original UK tuner to replace the US one.
I put the latest image on the disk and everything worked OK.
So the tuner must have been correctly configured by the palmod program.
See if you can confirm that the tuner is a TMDG2, it should be printed on the label.
jh

[len davis]

Sorry for delay in replying to your questions but have been laid up for a while.
The tuner is indeed the TMDG2 type as you thought. I am afraid that a lot of the stuff you are talking about is above my head, as I am in electronics side rather than software. I have just upgraded to a 120 gig drive and have a network card using tivoweb etc all ok, and phew that was a steep learning curve.
If anyone could give me exact details on what to try next it would be appreciated greatly.
Len.

[Darren King]

It is in fact an ALPS TMDG2-805A. The I2C information for the RF output is the same as the Samsung tuner and the control registers can be found in this document: http://minnie.tuhs.org/twiki/pub/Uploads/WebHome/S.pdf

The ALPS TMDG2-805A is what I fit to USA S1 TiVo's for people in Australia and we have UHF RF Output working quite happily on channel 60.