Professional custom satellite radio - "how-to" step by step. - PeachParts Mercedes-Benz Forum

Ray652 · #1 12-03-2007, 04:41 AM

Most of us will want to add satellite radio to our vehicles...R129 SL500 etc
In a small vehicle, every square inch is precious.
The ash-tray is wasted space for most people especially for those who do not smoke.
This space makes a very good spot to install and hide your new satellite radio.
Not all satellite radios will fit.
The Sirius Sportster worked in my 98 E300 but is too big for the R129
The Sirius StarMate Replay is one of their best models for this application.
You really want the Replay version .... being able to replay the last 44 minutes is a great feature.

Goals:

1. Professional radio installation using wasted space and make it "disappear" when not in use.
2. Add separate DC power jacks for an MP3 player, cell phone and for a GPS system
3. Add a "mute" button for when the cell phone rings - kills main amplifier audio so it will mute the sound system without regard to what the audio source is.
4. Add a switch to selectively raise and lower the standard antenna which is not used for satellite reception. Saves wear on the antenna (expensive) mechanism.
Tools required: soldering iron and regular small electronic hand-tools.
Here is a "step-by-step" on how to do it yourself.
1. Purchase your radio....can be had for $40 to $50 new.
2. Order the matching DIN face plate http://www.dogstarradios.com/stv2.html $20
3. Radio Shack for the DC jacks 2.1mm coaxial DC power jacks...$2.50
4. Radio Shack for 3 in-line fuse-holders with 2 amp "mini blade" fuses....$3.00
5. Radio Shack for screw-terminal barrier connection strip.....$2.50
6. Radio Shack for wire, heat-shrink etc.....
7. Radio Shack for a miniature toggle switch...push-on / push-off for mute function.
8. Radio Shack for a miniature toggle switch...on/off SPST ...$4.00 each

I have taken a few pictures from the beginning to the end of the 2 to 3 hour project.
While the photographs were not intended to be "wedding" quality.....I forgot to set the "macro" adjustment on my camera for "close ups" and did not look at the pictures until after the final installation was complete. Focus is not great but they are fine for the intended purpose....you will get the idea.
MP3 players cell phones and GPS receivers require either 12 volts DC or 5 volts DC.
The satellite radio is 12 volts
My GPS, a TomTom ONE 3rd edition requires 5 volts.
It comes with a 12 volt to 5 volt cigarette lighter adaptor but I made a new cable that connects directly to the 5 volt DC panel jack.
This bulky adaptor is messy and I removed the existing cigarette lighter DC socket along with the original ash-tray. This is removed with two small self-tapping screws, one on either side of the ash-tray. Remove the ash-tray, disconnect the DC connector and cut the 2 wires 1 inch from the socket. You need the male end of the DC plug to supply power to the new panel. See pictures. Store the 2 screws, small light bulb and ash-tray for the that day you sell the car although I cannot see why the new owner would not insist on keeping the satellite radio.....but you never know.
In order to supply the 5 volts DC to the GPS, I wired the TomTom adaptor as shown. 12 volts TO the adaptor and 5 volts FROM the adaptor....all wired to the screw-terminal strip. The adaptor sits inside the cavity left after removing the ash-tray.....properly taped up so as to avoid any short circuits. It now lives in the old ash-tray cavity.
Using the power connector taken from the original cigarette lighter, the 12 volts is supplied to the barrier strip for distribution.
Total current to be taken from this circuit is orders of magnitude LESS than the current drawn by the original cigarette lighter when pushed in. This circuit has its own, original fuse. Don’t touch it....MP3 player, GPS, cell phone and satellite receiver all ON at the same time!!
Each circuit on this new panel is individually fused at 2 amps each.
In addition, the GPS adaptor has a fuse also.
The 12 volt circuit is not active when the ignition key is removed.
The plastic DIN standard mounting panel is slightly too wide for the ash-tray in my R129 97 SL500.
You will need to shave off a few mm from the left and the right sides.
NOTE: the receiver is NOT centered on the panel.....it requires more space on the left side for the radio connectors....see pictures.
You will also need to cut the top right and left of the panel in the same manner and dimensions as the original ash-tray top right and top left corners are cut...see pictures.
This is required so that the final sub-assembly can slide neatly into the ash-tray cavity just like the ash-tray.
It starts out going in horizontally and then swivels upwards.... slide IN and then UP.
Think of Tom Cruise in Top Gun.......it will slide in perfectly but with no room to spare...so measure 3 times and cut once!!!
I have designed electronic equipment all my life and I am a stickler for esthetics.
Unfortunately, in this case, face-plate "real estate" is very precious and there are reasons why the DC jacks and the switch are placed where they are.
All connection jacks to the satellite radio are made on the left hand side when looking from the front.
The ONLY place for these added components are where I have placed them.....so as not to interfere with other plug connections to the radio.
This project was designed "on-the-fly" insofar as the jacks and switches were concerned.
Alas....there was room for the two DC jacks and only ONE switch.
I decided to skip the antenna switch for now in favor of the "mute" function.
I will find an alternate solution for the antenna switch later.
I suggest using different size DC jacks for the 12 volt and 5 volt outputs.
2.1mm for 12 volts and 1.7mm for the 5 volts ....that way you will not screw-up!!
These sizes refer to the center hole and pin size.......the outer mounting diameter is the same for both. Radio Shack / Fry's Electronics will know what you mean.
Feed the satellite antenna cable up behind the center console.
Remove your MB Becker radio using the correct tools...see Sticky - Becker Radio Data.
Place it face down to the left of the center console....next to your right knee if you are sitting in the driver's seat.
Locate the black AM/FM coaxial antenna cable coming from the main wiring harness which goes into the Becker radio on the rear right side looking from the front.
Feed the FM modulator wire from the ash-tray cavity to the rear of the Becker radio cavity above.
Wrap (coil) 8 inches or so of this single wire around the black coaxial antenna cable mentioned above.
Use electrical tape or plastic "tie wraps" to keep it place.
This will provide excellent "inductive coupling" of the FM modulator signal on say 88.1Mhz or whatever frequency you choose, to the Becker radio.
After final assembly, see pictures, slide the new face-plate with the radio in place into the ash-tray cavity.
Remember to place the GPS 5 volt cigarette adaptor into the cavity first and make sure its tucked away and fully insulated.
Now to secure the panel....
As a result of the top corners being removed, there is no support there when pressing any of the top row of radio buttons.
Using the original two screw holes used by the ash-tray would not provide adequate support.
I drilled 2 x one eight inch holes in the lower right and left sides of the panel....see pictures....about three eight inch from the bottom.
I used two small half inch black self-tapping screws to secure the panel to the console.
This procedure provides excellent support for all radio functions once they are tightened.
Do not over-tighten these screws....finger tight is enough!!
If you ever have to restore things, these two new holes are hidden behind the ash-tray when re-installed.
Closing the ash-tray door makes the radio disappear and since there is no heat issue, you can have the satellite radio operating with the door closed.
My satellite antenna is mounted behind the rear window near the trunk lid...see picture.
It is painted the same color as the car.......easily disappears unless you look very closely.
Later, after the holidays, I will design a small circuit that will sense when the cell phone rings (RF sniffer) that will automatically switch the "mute" circuit and silence the radio or CD player when a call comes in....manual and automatic option.
I really need this feature when I have Fleetwood Mac or Sandy Nelson beating their drums at ear-popping levels.....or when "Mrs Robinson" is doing her thing or Eric Burden does his "House of the Rising Sun".........this R129 sure takes me back to my teens and twenties!!!
I have not included a wiring diagram since it is so simple.
If anyone needs one...let me know and I will draw one up.

Life is short.....enjoy!

Ray652 · #2 12-03-2007, 04:44 AM

additional pictures....more below

Ray652 · #3 12-03-2007, 04:46 AM

final pictures.

I had no way of getting them in the correct sequence....but here they are.

Dee8go · #4 12-03-2007, 02:10 PM

That turned out pretty nice. Good job!

I am wondering why you didn't just go with the box in the trunk? Unless you're moving the reciever in and out between several cars and home, wouldn't that have been easier?

Ray652 · #5 12-03-2007, 07:38 PM

Quote:

Originally Posted by Dee8go

That turned out pretty nice. Good job!

I am wondering why you didn't just go with the box in the trunk? Unless you're moving the reciever in and out between several cars and home, wouldn't that have been easier?

well, I wanted it this way...so that I could see it and perhaps more importantly, I enjoy doing things.....keeps me away from getting married again!!!

no, its a peremanent installation...