Radio Gamma 5: Coding Options and Features

Hi!
I recently purchased a Gamma 5, and VAG-COM allows for several vehicle-specific sound codings. I'm curious about what exactly is being recoded in the process. In my attempts, I could only detect a change in the bass – is that all there is to it, or is more happening in the background? Also, I'd be interested in seeing the measuring blocks. Does anyone have the corresponding label file for that? There are only a few fields, but I don't understand 2 or 3 of them.

Thank you very much.
Dirk.

P.S.: Does anyone know of a simple way to properly connect an external audio source? I'd prefer to avoid using cassette adapters if possible...

Hi Dirk.

It has a strange connector on the back, and there's something like an 'audio in' port there as well. Bertil once posted about those connections for the hands-free device. Try searching for that. If you can't find it, Bertil will probably be able to help you best.

hi!
Great, thanks Joergs! I finally found Bertil's post after searching for a long time.

/viewtopic.php?t=2089&highlight=mute

That would certainly be a good way to do it through the phone line. However, I'm afraid that I would have to make significant compromises regarding the sound quality, wouldn't I? I imagine that first, the phone might only play in mono(?!) and second, there might be automatic audio optimization specifically for speech... Maybe Bertil could say something about this; he seems to know a lot more about it... perhaps also about the encoding formats?!

Have a nice Sunday still...
Dirk.

P.S.: Does anyone know of a simple way to properly connect an external audio source? I would prefer to avoid using cassette adapters if possible...

You can practically forget about using that. You'll need either a changer emulator or a CD player/changer with a modified cable to inject audio signals. Otherwise, the input won't be activated. My suggestion: Sell it on eBay (I got €100 for mine) and buy a radio from JVC or something similar (something you like that has an AUX input). Many older JVC radios had this feature, and newer ones often have an adapter available from JVC. The radio can be switched to either use a changer or the AUX adapter (so it sounds like a simple soldering job if you want to replicate it).

Information about the connector pinout: http://www.michaelneuhaus.de/golf/golf4stecker.htm#gamma

Best regards, WarLord.

@dirk

Without wanting to say anything wrong: Chamber 1, the blue part, pin 18-20 might possibly work. But Bertil probably knows more about that...

brezelmann01 wrote:

...Maybe Bertil can say something more about it; he seems to be much more knowledgeable in that area... perhaps also regarding the codings?!

Regarding the encodings, I can't say anything about them because the Gamma system is unfortunately not provided by my employer.

The telephone line only provides mono audio with a rather limited bandwidth (essentially telephone quality).

Using the switching interface (Jörg's suggestion), it's possible to implement an audio input, but unfortunately, you would have to trick the radio into thinking a changer is connected via the interface.

I solved it differently on my Gamma. Who needs MW anymore?

I desoldered one side of the two electrolytic capacitors that transmit the monaural signal from the AM demodulator to the electronic audio amplifier and placed them on RCA connectors. This allows me to connect any audio source (e.g., an MP3 player) to it.

@brunhilde
Not bad, but then the radio station appears on the display?!
Did you take a picture of it?

@brunhilde
But I understood correctly that it will then output only a single-channel signal, right?


Has anyone ever opened one of those adapters that are always available on eBay for way too much money? For example, you can see one like this under item number 2482587490. I am NOT related to or acquainted with the seller – unfortunately!
Perhaps someone could share what's going on inside these black boxes (photos?). If I understand correctly, a total of 6 wires are being used. Presumably, 4 of them are already dedicated to the audio signal. So, what happens with the remaining two? How is the changer functionality simulated?

Thank you very much.
Dirk.

@brezelmann01
A monophonic signal from the AM demodulator is fed to two capacitors (10µF), which then connect to the two inputs of the audio amplifier. Since I have desoldered the previously connected input connectors, this results in a stereo input.

I don't mind that the display shows 'MW' (medium wave) when playing MP3 files.