Becker Mexico Cassette '77 Bluetooth Upgrade

[Alex]

So I have a '77 280SE (Aus Delivered) with the factory Becker Mexico.
The Mexico is thankfully, fully functional with all seeking AM/FM functions working and cassette functionality.

However, I still want to have the option for bluetooth functionality on a switch (or automated one).

I did find this:
https://www.ebay.com/itm/294723236823?itmmeta=01HWXX4Z29Y6CKG3GZYP5XJGW2&hash=item449edfb3d7:g:cXUAAOSwk2lfnFZ8

And other similar ones that use the 7-8 pin connector at the rear of the stereo. Do they work through this connector only? How does this connector work? From my understanding- this connector allows me to connect an audio input midway after the stereo and before the amp. This should retain functionality for the original radio.

TLDR:
Anyone got experience with upgrading bluetooth onto the Becker Mexico? Or experience with any of the other aftermarket bluetooth adapters using the 7-8pin adapter at the rear of the stereo?

Cheers.

[mrkozzy]

Same thought process.
Following this article with interest.

[ptashek]

No personal experience here, but looking at the schematic I have on file for the Becker, your understanding seems right. The socket hooks right into the amplifier stage, and is described as "socket for record player or cassette recorder (stereo)". The adapter I'm guessing simply decodes the digital Bluetooth audio into an analog stereo audio input for the amp.

[Alex]

Welcome gents, I have since received a reply from the owner of the company roughly explaining the device. (For the Becker Mexico Cassette - It may be different for a Europa or other systems.)

Here is the purchase link:
https://www.ebay.com/itm/265827133506?itmmeta=01HWZHKTV7NSHSTAX7VRM9PYPY&hash=item3de4882842:g:v9MAAOSw~dZhnXnK

So this one should plug into the rear "Din" port for control, the radio functions as normal until sound is played through bluetooth.

As far as I'm concerned it works through a relay, which switches off when your phone disconnects or the volume is down.

I am still contacting the guy to find out whether or not the volume is controlled through the original volume knob or the phone.

Shall update when I find out.

[Max-NL]

Volume should be controlled through the radio, as the accessories which used that connection (external cassette player, trafic decoder) do not have volume control. This is handled via the radio.

[nathan]

before any solutions were available, I decided to devise the most complicated way humanly possible to have bluetooth and hands free powered by my Becker. behold!
https://www.youtube.com/watch?v=iSOtJ-sal5E&t=9s

[Alex]

Volume should be controlled through the radio, as the accessories which used that connection (external cassette player, trafic decoder) do not have volume control. This is handled via the radio.

Yeah can confirm through a second source that this is the case, so that's good.

--------------------------------------------

before any solutions were available, I decided to devise the most complicated way humanly possible to have bluetooth and hands free powered by my Becker. behold!
https://www.youtube.com/watch?v=iSOtJ-sal5E&t=9s

That's you!?!?

I saw that in my research. Fantastic job mate. My soldering skills are still, ok- at best.
I may try the off-the-shelf solution and report back.

[JP]

280S - Becker Monza owner here, I decided against using these 6-pin adapters and went for an alternative/cheaper solution. Installed a 12v lighter socket in a round hole of the steel frame on the left side of the trunk, and plugged a FM Bluetooth transmitter into it. I got the 12v feed from the + from the electric aerial. Chose the 88.0 frequency which in my area remains unused. The socket/transmitter gets power only when I turn on the Becker receiver and the aerial goes up. If I turn it off, it all goes off. If I want to listen to the radio or a cassette, I just tune another frequency or insert the tape. The whole setup is a tight fit and hides behind the trunk carpet.

Cheers!   

[Alex]

280S - Becker Monza owner here, I decided against using these 6-pin adapters and went for an alternative/cheaper solution. Installed a 12v lighter socket in a round hole of the steel frame on the left side of the trunk, and plugged a FM Bluetooth transmitter into it. I got the 12v feed from the + from the electric aerial. Chose the 88.0 frequency which in my area remains unused. The socket/transmitter gets power only when I turn on the Becker receiver and the aerial goes up. If I turn it off, it all goes off. If I want to listen to the radio or a cassette, I just tune another frequency or insert the tape. The whole setup is a tight fit and hides behind the trunk carpet.

Cheers!   

I considered something similar, I might do something similar as a temporary fix.

I really need the sound quality too,

I think the current best option is to relive the ash tray, file it out a bit, and put a second (very bland) radio in there. Use that to run a powerful amp, and put new speakers in the rear, and some additional ones up front. The Becker would only be connected to the front little ones (which is all that's necessary to be honest).

[c107]

This is a pretty old thread, but I went through a similar exercise with my 1977 450SLC, which is basically the same set up as on a W116 when it comes to radio and speakers. 

This is what I did.  I'm very happy with it:

1) Preparing the radio: https://www.classicjalopy.com/2023/05/450slc-becker-mexico-cassette-install-part-1-preparing-the-radio/
2) Upgrading the speakers: https://www.classicjalopy.com/2023/05/450slc-becker-mexico-cassette-install-part-2-upgrading-the-speakers/
3) Wiring Up the Becker: https://www.classicjalopy.com/2023/05/450slc-becker-mexico-cassette-install-part-3-wiring-up-the-becker/
4) Final installation: https://www.classicjalopy.com/2023/06/450slc-becker-mexico-cassette-install-part-4-final-installation/

PS: the DIN port on a mexico is Mono only for the traffic connector.  You can tell as it only has two pins.   The DIN port on a Europa II or a Grand Prix is Stereo for the external tape deck.   

[Alex]

This is a pretty old thread, but I went through a similar exercise with my 1977 450SLC, which is basically the same set up as on a W116 when it comes to radio and speakers. 

This is what I did.  I'm very happy with it:

1) Preparing the radio: https://www.classicjalopy.com/2023/05/450slc-becker-mexico-cassette-install-part-1-preparing-the-radio/
2) Upgrading the speakers: https://www.classicjalopy.com/2023/05/450slc-becker-mexico-cassette-install-part-2-upgrading-the-speakers/
3) Wiring Up the Becker: https://www.classicjalopy.com/2023/05/450slc-becker-mexico-cassette-install-part-3-wiring-up-the-becker/
4) Final installation: https://www.classicjalopy.com/2023/06/450slc-becker-mexico-cassette-install-part-4-final-installation/

PS: the DIN port on a mexico is Mono only for the traffic connector.  You can tell as it only has two pins.  The DIN port on a Europa II or a Grand Prix is Stereo for the external tape deck. 

That's a nice job you've got there.

Looking back on this thread, I swear I must have been on something to think that the dual system idea by splitting the front and rear speakers, or adding additional ones was good or viable haha.

Currently, I am running a Bluetooth FM transmitter. I found that most transmitters won't fit in the ashtray, or work with that port (my lighter is also jammed).

So instead, I removed the ashtray and tapped the 12v from that connector by using two (6 or 8mm?) bullet connectors and soldering on the adapter to the end.

I drilled a tiny hole in the corner of the glovebox, passed the cable through and voila. (Also reinstalled ashtray, with now not functioning lighter) It's not perfect, but temporarily I have USB, Bluetooth audio, all whilst retaining the original radio function, casette power, the fader, and without ruining the interior aesthetic by being completely hidden from view.

This works for the time being, but it's nothing fancy. Considering this car is my DD it's a huge upgrade for sure.


TLDR:

Bluetooth upgrade through tapping 12v from cig lighter and using FM transmitter- is a good and cheap way of adding modern features whilst being 99% hidden.

————
CURRENT PLAN.

My rear speakers, having lived in the heat of rural NSW are completely kaput. They rumble buzz and pop. (I just send the fader full front for now).

I want to replace all 4 speakers regardless.

My genius shower thought idea is to put a signal switch or relay AFTER, the stock amplifier. The stock amplifier outputs two little cables. I suspect these are a stereo pair L and R. This then goes to the fader, ya di ya da. I could have an additional stereo + amp hidden in the glovebox, and have that + the original two channels join into a junction. Then have the output be 1 output to all 4 speakers.

By simply switching the input you want, you can choose whether you want original audio or the new system.

Cons / tricky bits.

- Requires 4 speakers that are compatible and work nicely with both the original Becker and a new powerful amp. Where do I find, or how does speaker resistance and sensitivity work? No clue.
- Requires a location for a switch to swap between audio sources, and a volume knob for the new amp. (Perhaps use the fader?).

I was thinking of just adding an isolator switch on both stereos when not in use, or only one is being used. Just to conserve power from the battery. I think just a simple toggle switch somewhere inline on the power lead should suffice.