CPI 400/2000 radio MM5221ESD chip availability?

[Retroradio]

Some research has shown that chip is not really available out there in the wild. Looking for a MM5221EDS/ N.
Does anyone know if there is a supplier who carries one NOS or confirmed good used?
My local shop has informed me I need one and they cant find one...doesn't look good...

Mods, if this type of post is not allowed, please delete. Thanks

 

[KB4MSZ]

If you are willing to pursue this possibility, it shows up on this Japanese parts sourcing site:
在庫・部品リスト｜みつかるどっとこむ

This is what the heading translates to:


This is the inventory information of the partner supplier. Market inventory is fluid, so you need to check again.
Please proceed to the inquiry form from the request for quotation form button in the upper right buhin@mitsukaru.comemail to the request for quotation.
※ Request for quotation is free of charge. If we find the part you requested, we will
first issue you a quotation. Since procurement charges are included in the estimated amount, the estimated total amount will always be 10,000 yen or more even for cheaper parts. Please understand in advance.

Parts List (1)

Parts List (2)

Parts List (3)

Unfortunatly, 10,000 YEN = roughly $100.00 USD

 

[Retroradio]

Wow! Thanks for the info...Figured it might be pricy but was hoping for a little less and on this continent...lol Great info though.

 

[Retroradio]

Tumbleweeds I guess...lol
I have posted same in another forum and no answer either...

 

[ll_Cartel_ll]

https://www.rfparts.com/mm5221eds.html

 

[ll_Cartel_ll]

I have the chip in my digicom 100. not sure if rf parts is the same program on it

 

[merlin]

I would like to see a datasheet and application doc's for this chip.
It would sure cut down the parts count for a back burner project in mind.

 

[Retroradio]

View attachment 103947

I have the chip in my digicom 100. not sure if rf parts is the same program on it

Does anybody know the correct part number for this chip in the CPI 400. I have scoured the net, looked at repair videos and am now not sure what the correct chip is. The digicom was 23 channel (that could be reprogrammed to 40 acording to the net). I have found the part number for the CPI 2000 but no info on the 400.
I’m not even sure off I find one If it would be a straight drop in so to speak. My CPI has been sitting here for about 5 years and no luck so far. Even my local shop said the chip is not available and couldn’t repair it.
ThaNks for the help So far but am trying to get this beast up and running.

 

[tramd]

The parts list for the CPI 400 shows it as Part# U600N and is a MM5221 EH/N. The CPI 2000 uses a MM5221 EDS/N or the MM5221 EYW/N The 400 and 2000 are basically the same radio. Their schematics are the same except for the added features the 2000 has. Some of the ICs are PROMS and some were EPROMS. EPROMs have a window so they can be erased and reprogrammed. The window should always be covered with a sticker or tape to prevent ultraviloet light from erasing it over time. The 2000 in the first pic has the MM5221 EYW/N. The CPI 300 (or it may be an early 400) in the 2nd and 3rd pics has the PROM MM5221 EDS/N to give it 40 channels. I have a 300 with a MM5203Q EPROM that gives it 40 channels and with some mods 79 channels.

 

[Retroradio]

The parts list for the CPI 400 shows it as Part# U600N and is a MM5221 EH/N. The CPI 2000 uses a MM5221 EDS/N or the MM5221 EYW/N The 400 and 2000 are basically the same radio. Their schematics are the same except for the added features the 2000 has. Some of the ICs are PROMS and some were EPROMS. EPROMs have a window so they can be erased and reprogrammed. The window should always be covered with a sticker or tape to prevent ultraviloet light from erasing it over time. The 2000 in the first pic has the MM5221 EYW/N. The CPI 300 (or it may be an early 400) in the 2nd and 3rd pics has the PROM MM5221 EDS/N to give it 40 channels. I have a 300 with a MM5203Q EPROM that gives it 40 channels and with some mods 79 channels.View attachment 107064 View attachment 107061View attachment 107062

Awesome, many thanks for the detailed info. At least now I know which chip I am looking for To get my CPI400 upo and running. Apparently these are made of unobtainium but…..the search continues.

 

[tramd]

There is a CPI group on Facebook. You may find some one there that has one. Not likely, but worth a try.

 

[prcguy]

If the part is just an EPROM you should be able to read a good one and extract a truth table. Then there are probably lots of electrically compatible EPROMS or PROMS that you could burn to give the exact same function. Worst thing you may have to do is make an adapter board to fix any differences in pinouts.

Another thing you might be able to do if you have a pinout of the original part is experiment with the EPROM output pins in the radio and identify what programming lines are for MHz, KHz, etc, and then you can at least strap the radio with jumpers to get a particular frequency.

A friend of mine has my old CPI 300 and maybe a 400. They have various problems but the EPROMs should be ok.

 

[prcguy]

Here is some info on the part, it looks like a real odd bastard.

 

[Retroradio]

If the part is just an EPROM you should be able to read a good one and extract a truth table. Then there are probably lots of electrically compatible EPROMS or PROMS that you could burn to give the exact same function. Worst thing you may have to do is make an adapter board to fix any differences in pinouts.

Another thing you might be able to do if you have a pinout of the original part is experiment with the EPROM output pins in the radio and identify what programming lines are for MHz, KHz, etc, and then you can at least strap the radio with jumpers to get a particular frequency.

A friend of mine has my old CPI 300 and maybe a 400. They have various problems but the EPROMs should be ok.

YUPP, thats the issue I cant find one…. I know its like the Stoner Pro40 not many have seen them but they exist.
Thanks for the good advice as always. The search continues.

Thanks for the info on the part. Really odd part …..lol Great radio though

 

[tramd]

Years ago there was a Yahoo CPI group and a few on there had spent a considerable amount of time and effort to find replacement EPROMS and/or PROMS but were never able to come up with a programmer that could program them due to the voltages needed from the programmer for certain pins on the chip. They finally gave up. I used to work at a place where we programmed lots of different types of EPROMS, PROMS and PICS. The software for the equipment we produced was on these and as many as 15 EPROMS would be on some of the cpu boards. We were always doing software upgrades and reprogramming old chips as well as programming new ones.The programmers ("burners" as we called them) could install just about anything on any chip as long as you had a copy of the original or had an original EPROM or PROM to copy from and had the correct EPROM or PROM to burn it to. Too bad that company isn't still around.

 

[prcguy]

A few minutes with a volt meter will tell you if the input from the channel selector side and the output to the synth side is TTL or not and I suspect it is. All the part is doing is providing a mapping from its input to its output and that can be replaced with many different PROMS, EPROMS or even switches. In most cases the input goes from 5v to 0v to select a specific map then the output goes from 5v to 0v to program the synthesizer.

I looks like there are 7 input lines of which only half are probably used and 8 output lines to the synth. Most common PROMS or EPROMS will not use the -12v and would only connect to 5v and the input/output lines. Something like the old 2764 EPROM might work and there are lots of cheap programmers out there for that series. I think I have one in my garage somewhere with a stick of EPROMS.

 

[VK3RX]

FWIW in post #9 the second and third pix are of a CP400 I used to own.

That particular chip in it was a replacement for the original, giving "99" channels (I say "99" because there were about 60 unique channels to 27.505 and the rest were duplicates). The chip was popular in the day but unfortunately it seems few kept the original 40 channel chip.

To return the CP400 to "stock" I also was after either an original chip, a copy of one or a replacement PROM, but as tramd said, on the Yahoo Group it came to nothing, and I ended up picking up a battered and dead CP400 which at least had a good original chip in it.

 

[Retroradio]

FWIW in post #9 the second and third pix are of a CP400 I used to own.

That particular chip in it was a replacement for the original, giving "99" channels (I say "99" because there were about 60 unique channels to 27.505 and the rest were duplicates). The chip was popular in the day but unfortunately it seems few kept the original 40 channel chip.

To return the CP400 to "stock" I also was after either an original chip, a copy of one or a replacement PROM, but as tramd said, on the Yahoo Group it came to nothing, and I ended up picking up a battered and dead CP400 which at least had a good original chip in it.

That’s where I have ended up. I figure from the thread getting the chip is not a straight drop in. Hence I am now after an original chip as well. The problem of course is at least here these units are $500 and up and nobody logically is going to part out a working CPI.
Looks like the hunt continues and am still stuck with a display piece as it has the power supply/speaker unit as well and looks impressive….lol

 

[tramd]

FWIW in post #9 the second and third pix are of a CP400 I used to own.

That particular chip in it was a replacement for the original, giving "99" channels (I say "99" because there were about 60 unique channels to 27.505 and the rest were duplicates). The chip was popular in the day but unfortunately it seems few kept the original 40 channel chip.

To return the CP400 to "stock" I also was after either an original chip, a copy of one or a replacement PROM, but as tramd said, on the Yahoo Group it came to nothing, and I ended up picking up a battered and dead CP400 which at least had a good original chip in it.

That's pretty cool that was your radio. I can't remember where I got the pics from. I think from Yahoo's group. You must be familiar with Frank Wolfe and the guys on the CPI FaceBook group. Many are from AU.

 

[prcguy]

When I bought my first CP300 new in the late 70s I also bought the 99ch chip and never got that working. You had to plug it in then do something else like install a jumper or make a change on the board. I might have included that 99ch chip when I sold the radio to a friend and he still has it and another CPI, both which are not working now.

FWIW in post #9 the second and third pix are of a CP400 I used to own.

That particular chip in it was a replacement for the original, giving "99" channels (I say "99" because there were about 60 unique channels to 27.505 and the rest were duplicates). The chip was popular in the day but unfortunately it seems few kept the original 40 channel chip.

To return the CP400 to "stock" I also was after either an original chip, a copy of one or a replacement PROM, but as tramd said, on the Yahoo Group it came to nothing, and I ended up picking up a battered and dead CP400 which at least had a good original chip in it.