Adding Bluetooth to a Sanyo MCD200

[oVeRdOsE]

Bought this 1987 sanyo box from ebay, 99% pristine condition. My parents had one before I was born and it was my first contact with sound system. Nostalgia buy.

DISCLAIMER : Its not build in a pretty way nor in a correct way. I did not want to spend money on it, I did this what I had laying around from an other build. ALSO, I wanted it 100% reversible, so no cutting nor permanent glue/screw.

-The amp barely fits, its glue with double sided tape.
- Amp input are original amplifier output (no I dont have noise). like so, I keep the original functionality of the unit.
-Since this MCD200 don't have any aux input, I had to find an input source. I choose the tape chip, and plug the BT chip to the out1 and out2.
-To avoid noise, I add a DC-DC insulator, 5v is from the amp board.
- Since the original power wiring this box is about 30ga, I add a cap for the 12v supply , doubt it does a thing but better than nothing.

Luckily I found the tape preamp chip specs.

I used the original powersupply, 16v 30w, to charge the battery pack. I add a step down converter ; 16v to 12.6.

- I use Boston power 4400mAh batteries from my dead Neato robot vacuum
- PCB 3s 20A
- Silver switch is for cutting the battery from the boombox, not useful , it was just in case
- Since I have to press the play botton on the tape casette player to activate the preamp , I add a red switch to stop the motor (reduce noise). I didn't find a other way to activate the chip

-Unit remain 100% functional, even the tape cassette.
- Volume is controlled by the original slider
- About 6h of playtime.
- It charges @6w, so about 10h of charge time.

-

Original speakers were too weak, so I changed them with SB acoustic , add a Denon crossover, and add some wool.

Had to trim the speakers since they were 0.5'' smaller (original are 4.5'')

 

[PostEnder]

Hi, there, oVeRdOsE. That certainly seems to be good work that you've put into that project: modifying your SANYO MCD 200 with Bluetooth connectivity. You state that buying this single-cassette-deck, CD player boombox with detachable speakers was for old times' sake: "Nostalgia buy," as you wrote. Well, this modification will bring the usability of this mid- or late-Eighties sound system fully into the third decade of the 21st century. Or pretty close to it, at any rate.

What model number of SB Acoustics speakers did you opt for in making the modification? The Magnifier feature of the Photos app' of my computer seems to help me make out the model number SB12NRX25-4. Alas, mine isn't marvellous eyesight, but is that model number correct? I suppose that the model number of your chosen SB Acoustics isn't SB12MNRX2 -25 -04, although both speakers' model numbers (and perhaps also their specifications) are similar. (The SB12MNRX2 -25 -04 was found on the MadisoundSpeakerStore.com website with a Google search for "SB Acoustics Speakers.")

The descriptions you share with us of the alterations remind me of those stated (I suspect) many times by Teddy Hashee, the relatively YouTube -famed repairer and restorer of vintage boomboxes and mini-boomboxes (among other things). I remember him stating the need to do a "step -down" of the voltage originally engineered into the portable sound system from, say, 12 volts or 15 volts to 5 volts to accommodate the Bluetooth connectivity in various boomboxes that he has worked on in his basement (I think) in the North eastern United States. The alterations that Mr Hashee works on usually go well, as his interesting videos show -- at times after a lot of trial and error LOL. I'm glad that your project was a success as well. (I suppose you did mean a "DC-DC insulator," not a "DC-DC isolator.")

Yes, I've said often enough here on BoomBoxery.com and on another boombox fan website that I tend to prefer the shortwave-tuning feature in my boomboxes, even though people will say that shortwave (SW) is close to extinct as a relatively popular broadcasting format, that SW DXing is barely decipherable (except perhaps with very expensive, all digital world band receivers connected to very expensive antennae), that SW has inconvenient listening times, that SW radio is dominated by evangelical programming that isn't very popular, etc. Your unit only features the more familiar domestic radio bands: FM and AM (AKA MW, for "medium wave"). Sanyo did make an SW tuning version of the MCD-200, as a Google search shows. So I wonder: did your dear parents' Sanyo MCD-200 have SW bands? And does the built-in digital clock still work? It would be a pity if it still works but isn't in use nowadays due to the need for an "AA" battery. (And, of course, your fifth photo' shows the battery bay busy holding integrated circuit board [ICB] parts for the mod'.)

Ah, well, maybe no matter: your inspiration to do the mod' and your technical skill are commendable and respectable.

Enjoy good music with you updated stereo, okay? Maybe an old breakbeat cassette you find, maybe symphonic performances piped into your home via the Bluetooth link. Thanks for sharing.

 

[oVeRdOsE]

Thanks for your comments !

Sb acoustic model is SB12NRX25-4,

Power Handling (RMS)	30 W
Frequency Response	55 Hz
Sensitivity	87.5 dB

Step down is only for the battery pack charge, since the PCB doesn't regulate voltage but only cut it out , I need 12.6v to avoid overcharge the unprotected lithium pack.

5v is from the amplifier, so stepdown is already embedded into the board. DC-DC isolator, correct. I had this idea from DIY perk youtube channel.

Most canadian radio tuner came only in AM and FM band. no sw. Yes Sanyo in general got the sw, but not in america.
FM still useful, we have a lot of interesting shows and music. AM is pretty much dead.