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I installed DAB (Digital Audio Broadcast) into my R172. For US owners, option 536 SDAR would be the same installation. Only a subscription would also be needed.

For pictures on how the cable duct on the floor on the passengers side looks, see my post on retrofitting the Blind Spot Assistant.
 

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I'm tempted to go into doing this, considering there is so much work (the more, the better :) ); and even better, no SCN is required.

I was also looking into doing both the DAB and TV tuner together, but then I realized I probably can't, as it appears there is no MOST cable for TV <-> DAB, only HU <-> TV and TV <-> UMI/HK (leaving the DAB out), meaning they probably exclude each other.

Did you also notice this exclusion, and did you take into consideration both?

I also have a few questions regarding the "how to"; Considering that this is the preferred order:
HU <-> (TV / DAB) <-> UMI <-> HK <-> HU


1. You mentioned that you used two MOST cables (A1725403007), as per the pdf: "(you need two!)"
The DAB has red 2 plugs (I'm assuming those are the optical plugs). Isn’t 1 input, from the HU to DAB and the other one an output from DAB to UMI/HK/HU? (so part number A1725400507 should be required as the second cable (if connecting DAB to UMI)).

2. Or considering that these cables should probably be the same, internally, I could easily use the already existing cable from HU <-> UMI (as I have it currently) to DAB <-> UMI (as it should be, after adding DAB).

3. You mention in the pdf: "DAB tuner (be sure to watch for DAB 1&2 support)" - What do you mean by "1&2 support"?

4. Have you found DAB to be useful? :p
 

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That's a list of questions!

There are two optical orange cables needed. The different part numbers for these cables is about the length and nothing else. You can get optical cables from other suppliers than MB once you know the length you need. MB doesn't post the length per part number. You're cutting into an existing loop so disconnecting the UMI cable to allow it to go to the DAB wouldn't work because of the length of the cable. Now you can extend the existing cable with another short one or replace the existing short one with more meters. Next thing is to get from the DAB back into the loop, in this case to the UMI port. In principle it doesn't really matter in which order the devices are in the loop, but I found that at least the HU is a MUST to be the first one. The bugger is in the HU software where you switch the DAB 'on' and you can only do that on a free location in the existing list. Meaning it will be the last one. There is however a second list in the software which you cannot control. It is either hard coded or dynamically detected when the HU is switched on. Since I had intermittent problems with the DAB ignoring this second list (order), I experimented with the order in the loop and found that these problems went away adhering to this second list. Meaning, first I put the device in (at a more or less random position in the loop, it wasn't even in the trunk), activated it in the HU software and then adjusted the order in the loop according to the 'fixed' list of devices. I worked with this temp situation with the DAB on the floor of the passenger seat and having the necessary opticals from UMI, HU, AMP lying bare and (important!) the blue activation point which is close to the AMP.
Maybe there is quicker way, but this is how I got it in a position where it worked.

There are two DAB tuner versions in the world. The R172 works only with DAB-2. I think it has something to do with the frequencies it operates on. The DAB tuner is a MB device that is fitted to many models, the earlier ones working with DAB-1 tuners.

The DAB is a heap of sh*t. When in Germany it is 'satisfactory' but the signal is lost so many times when in NL, I don't bother with it. I THINK the reason is the poor reception options in the R172. There is one antenna in the front window whilst most MB models have two antenna's, one being in the shark on the roof. The DAB tuner has two antenna plug holes available. The R172 can get a shark on the trunk but that is for option 386 (telephone) not the DAB. I've experimented with a non MB antenna going into the second port of the DAB; nothing changed. I found that there are pre amplified antenna's and non amplified. Meaning one has 'power' to it. I didn't dare to put one with power into this DAB port, afraid of blowing the whole thing. MB is unclear in what kind of antenna this DAB tuner needs. The dealer didn't know either, they just add stuff that is in a OEM booklet and since the R172 only 'needs' one antenna, that's enough for them.

TV & DAB is only a theoretical possibility. I've tried to get to the TV parts but they are meant for Japan and Korea and they do not have DAB. The dealer was slammed by MB after weeks of parts being in back-order. If you really want to do this it will be a custom job.


I still have various optical cables in my shed. Ping me off line if you know what length you need.
 

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I have now finished doing this retrofit.
Everything works well, except I had an error in Xentry, due to the DAB not showing up in the loop (see attached picture, fields were read only).

This issue could had been also solved with SCN Online coding.

I solved it in Vediamo, as shown in the attached picture (currently in simulation mode, but live is the same).
Select each the value for each position.

It is recommended to respect the ordering, when you do the MOST wiring, because otherwise, even though you adjust the order here, should you do an SCN online coding, the ordering will be the 'default' one, which is described above.
 

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