Hi all,

I'm looking for the following Philips IC's for a Philips/Magnavox CD650 player. It was a top-rated CD player in the 80's, with the legendary TDA1541 DAC, and shared much in common with the BeoGram CD-X and CD5500. It would be such a pity to junk it.

Philips Part# 4822 209 11416
MAB8441P/T082 IC DIP28
 
Philips Part# 4822 209 72047
MAB8461P/W079 IC DIP28

If anyone has one or both of these NOS, please advise.

These parts were also common to many other Philips and Marantz CD players, among others, which all used the TDA1541 DAC.

Or, if anyone knows what to do to adapt a MAB8441P/T088 (which I have new, but doesn't work - each version of the MAB needed its own unique compensation circuit)

Regards
M Yachad

Hello

Sadly I don't have the ICs, but I would just like to wish you luck.  I had an 850, and it was a superb machine. 

eBay should be able to offer a few players that have what you need, and those early CD players sell for almost nothing at all these days, because no-one knows just how good they are...

Good luck!

These were all mask ROM programmed microcontrollers. Are you sure you can just get one from somewhere and plug it in? Normally, these would have been ordered by the thousands from the factory by the original equipment manufacturer, who wrote the code to suit their device, and never end up on the open market.

Then again, the suffix might denote a different program and be enough to differentiate them if they were used more like a reference design.

I still have a similar problem with my Beomaster 5000 and the blown 8751

Good luck with the search.

I still have my CD650, it is an excellent unit.  It is  also built like a tank and will probably last forever!

Simon

Hi Mika,

Thanks for that info. I did not know that each Txxx suffix meant a specific and unique embedded code.

That explains why my T088 does not work!

I've done various mods on it over the years, which give a beautiful sound.

My actual problem is a flashing, or dark display, with no functions.

Various tech websites point to the MAB8441P/T082 as the culprit, with Pins 2&3 showing voltage, but no data on the scope, which is exactly my symptom.

Now, as you see in the picture, the IC is made by Philips and installed in a Philips CD player.

So that could imply that another new /T082 has a high chance of success.

I found a web source in Estonia, which lists them for sale at about $7 each.

Philips Part# 4822 209 11416
MAB8441P/T082 IC DIP28
 
Philips Part# 4822 209 72047
MAB8461P/W079 IC DIP28

Of course, I don't speak their lingo, but perhaps someone on the forum in Europe could volunteer to check for me whether they have them in stock, and let me know. If they do have in stock, I'd certainly want to buy 2 of each for future eventualities.

Regards

Menahem

yachadm:

Thanks for that info. I did not know that each Txxx suffix meant a specific and unique embedded code.

That was just a theory, but I'm sure they had to mark the chips with different firmware somehow, and the datasheet didn't seem to give any other meaning for the suffices.

I found a web source in Estonia, which lists them for sale at about $7 each.

http://www.opood.ee

Philips Part# 4822 209 11416
MAB8441P/T082 IC DIP28
 
Philips Part# 4822 209 72047
MAB8461P/W079 IC DIP28

Of course, I don't speak their lingo, but perhaps someone on the forum in Europe could volunteer to check for me whether they have them in stock, and let me know. If they do have in stock, I'd certainly want to buy 2 of each for future eventualities.

I see they have a shop (actually two) in Tallinn, so there's a good chance they speak Finnish According to the web page, they have four pieces of the former chip in stock.

If nobody more fluent in Estonian volunteers, I'll see what I can do. I might actually visit there in a month or so and pick these up if delivery isn't possible.

Hi Mika,

Thanks so much!

Please keep me advised - of course if they can ship it quickly, even better.

And I will take all 4 (if you don't want any, of course).

I never know when I will have another CD player in for repair, with the TDA1541 chipset combination.

BTW, what is the problem with the BM5000 - what is that chip and its symptoms?

Menahem

yachadm:

Please keep me advised - of course if they can ship it quickly, even better.

And I will take all 4 (if you don't want any, of course).

I'll email them lated today and ask if they can ship to Finland (I can forward them to you no problem). I don't need any myself Also, a cow-orker of mine maybe has a friend that could pick them up, I'll hear about that later.

Just to clarify, did you find the latter chip there as well, as I didn't?

BTW, what is the problem with the BM5000 - what is that chip and its symptoms?

See here - I used to make a living designing and programming systems around this controller family 15 years or so ago, so I'm pretty sure my diagnosis is correct... I've been waiting for an externally trashed unit to come up so I could build one working and presentable BM5000. Or maybe I'll ditch both the 8751 & 8255 from the CPU module and replace them with an AVR so I would finally have a receiver that works exactly as I want it to

The MAB84* is actually based on Intel 8048, an (even more) archaic predecessor of the 8051 family. Programming them inflicted brain damage on the programmer

Hi Mika,

A man of many talents!!

Eero in Talinn replied to me and confirmed that 4 are in stock at Eu4.40 each. That is a super price.

I advised him that you would be contacting him to confirm the order.

So, please go ahead and let me know how much I should send you, including shipping.

On your BM5000, I'm not familiar with the 8751 or 8255 - what are they? There are a couple of places here which sell obsolete IC's - I can check for you, if I have the complete part number.

Do you want to make an AVR Automatic Voltage Regulator - perhaps I can help you there. What volts and amps in and out?

Thanks

Menahem

yachadm:

Hi Mika,

A man of many talents!!

Eero in Talinn replied to me and confirmed that 4 are in stock at Eu4.40 each. That is a super price.

I advised him that you would be contacting him to confirm the order.

So, please go ahead and let me know how much I should send you, including shipping.

Please don't worry about the costs yet - I'll wait and see what they have to say about shipping them here, I guess payment would be the only problem. I can probably send them in a tracked letter from here to Israel, and it will be at most 16 euros, probably less depending on weight.

On your BM5000, I'm not familiar with the 8751 or 8255 - what are they? There are a couple of places here which sell obsolete IC's - I can check for you, if I have the complete part number.

Do you want to make an AVR Automatic Voltage Regulator - perhaps I can help you there. What volts and amps in and out?

8751 is once again a mask ROM microcontroller, so there's no generic replacement - only one from a Beomaster 5000 will do. 8255 is an I/O expander for it, those are no problem to source.

"AVR" in this context means the 8/32 bit RISC microcontrollers by Atmel - for fun, I was planning to "recreate" the brains for this Beomaster, replacing the original controller+expander and a bunch of other stuff from the CPU module with a modern microcontroller and my own software. Even the most basic $5 AVRs will have tens of times the processing power of the original CPU...

Technically, it would not be much of a problem with the exception of remote control, which would need lots of reverse engineering (and I would need a working original Beomaster to make any sense of the two-way traffic). Implementing the basic functions would still take days if not weeks, so financially this would be a useless project... but it would be fun to have a Beomaster 5000 which works with all the modern remote controllers

yachadm,

you have a PM.

This is a BIG, BIG, BIGGGG thank you, in the most public way, to Mika Iisakkila.

He took care of sourcing the IC's in Estonia - Mika's Finland being close by.

My CD is up and playing again, better than new - and 22 years old.

The forum members are great people - looking beyond borders to help one another.

Way to go, Mika!!!!

Menahem

Great! I was a bit worried that there might be something else regarding the firmware versions than just the suffix of the chip, but now we know! My pleasure

The only bad part is that this source for replacements is now dry as well...