AMI R-81 Memory Unit

[James McClave]

Still looking for one of these. If anyone has a good one, give me a
holler. Thanks.

E-mail us at: ***@webtv.net

[Ken Layton]

Try here:

http://www.rowejukeboxrepair.com/

[James McClave]

He is the one that told me mine is bad. He could repair mine, but is
kinda pricey. Was looking for one a bit cheaper in price. He wanted 3
times what I paid for the whole jukebox to repair one module, Jim

E-mail us at: ***@webtv.net

[KR]

Post by James McClave
He is the one that told me mine is bad. He could repair mine, but is
kinda pricey.  Was looking for one a bit cheaper in price. He wanted 3
times what I paid for the whole jukebox to repair one module,  Jim

It sux, but even when the special IC (which is the cause of problems
with these units) was last still available, in the early 1990s it was
about $120 from rowe distributors.


You then have to fit it, etc.

[Ken Layton]

That unit used some special/custom components that have long since
been obsolete/discontinued. When you can find them, the price is very
high.

[James McClave]

If they are obsolete /discontinued , etc. Where is he finding them? He
seemed to have a good supply. I bet there is some substitute out there
somewhere. Jim

E-mail us at: ***@webtv.net

[KR]

If they are obsolete /discontinued , etc. Where is he finding them?  He
seemed to have a good supply. I bet there is some substitute out there
somewhere. Jim

You would need something like a PIC, AVR, CPLD to substitute, and
someone has to write the software for it, this is the hard part. The
chip ROWE used is not a simple logic gate, the IC has internal RAM -
that's also battery backed up, bidirectional serial comms (sort of)
port, (though probably more like an I2 squared design).
The only good news is that the communication protocol is described in
some detail in the service manual.

The same applies to the selector logic, Memorec unit and credit
computer. Each is a special custom IC.
(for home use you can probably do without the Memorec and credit
computer if they fail) but you need the memory unit and selector logic
for the machine to function.

Also the IC (and the whole system) is designed around negative supply
voltage (-17v) which, while possible to do, is a pain in the arse to
design around with modern chips. Modern microcontrollers use +5v (or
in some cases 3.3v). You would have to look at a replacement board,
or rider board rather than just the chip.

Remember too that this system is VERY old - the earliest date stamp I
have seen on these boards is 1974.
The design probably dates back to the early days of this sort of
technology coming into more common use, they probably paid an absolute
fortune back then to have these chips and modules designed and
manufactured, specially for just this purpose and nothing else. It was
probably took a huge risk going to this technology, I wonder what the
operators thought when they saw a totally silent black box replace a
search unit, button bank, etc ? It probably scared the shit out of
them, as to what to do if anything went wrong.

Being straight MOS technology, they are very sensitive to static
electricity also.

Also note in the manual where they discuss desoldering IC's, there is
nothing at all mentioned about anti-static procedures - except
attatching a ground wire to the iron, or touching it to a grounded
surface before using (shudder).

[James McClave]

Good info! Thanks . I will keep looking for a memory unit thats good or
will end up parting out my R-81 . Jim

E-mail us at: ***@webtv.net

[KR]

Good info!  Thanks . I will keep looking for a memory unit thats good or
will end up parting out my R-81 . Jim

what exactly is the problem you are having with it ?

[James McClave]

When you make a selection , it just scans past it and wont select any
record. Memory unit is bad , had it tested by the guy in new england ,
The micro processor chip is bad. Jim

E-mail us at: ***@webtv.net

[KR]

Post by James McClave
When you make a selection , it just scans past it and wont select any
record. Memory unit is bad , had it tested by the guy in new england ,
The micro processor chip is bad. Jim

Sounds like it, its just that one problem we had frequently many years
ago (where the numbers on the display werent counting in proper
sequence sometimes as the magazine scanned, and the magazine might
scan constantly) could be cured by adding 9 x 10k 1/4 w resistors
from the encoder wheel signal lines (9 of them - one resistor per
signal line) where they entered the chip, to the -17v rail.
Please use anti-static procedures (earthed wrist strap, earthed
soldering iron tip, earthed anti-static mat etc) if you decide to try
this.

I have had a third machine come in today from a person who has it in
home use with one of these "memory units" dead today. I'm starting to
warm more and more to the feasibility of designing a modern micro
controller based substitute, otherwise a lot of these machines will be
scrapped. (unless someone out there has already designed a replacement
board)

Even if there was a supply of NOS chips around, the expense of them,
and high failure rates they have means that there is a high risk of
you spending a lot of $$ to only have the same problem happen again in
the future.
If you dont care about keeping the machine original internally - (ie:
playing actual records) then consider one of these MP3 conversion kits
that are designed EXACTLY to retrofit record mechs, and make the juke
look and work normal from the outside. http://www.cdadapter.com/jcu.htm

you would have to:

-Do small modifications to the display and keyboard circuit boards
-Make a wiring harness to suit and provide a 13v power pack for the
replacement board
-Rip your records into MP3 and load them onto the CF or Hard drive.


The advantages are
Ability to load any song you want in there - even if not released on
vinyl
Not have to buy expensive 45's, range is probably very limited by now
not have to replace needles, repair mechanism, or worry about memory
unit problems
Replace unused "b" sides with other songs that you will play.

[James McClave]

Wow , lots of good info there. The resistor idea sounds kind of tedious.
Not crazy about the MP3 idea either. Yes, the numbers when scanning did
not read in sequence either. Too bad, from what I know this memory unit
was only used in this model and maybe the R-82? Jim

E-mail us at: ***@webtv.net

[KR]

Post by James McClave
Wow , lots of good info there. The resistor idea sounds kind of tedious.

Give it a go, you have absolutely nothing to lose,
if the chip is indeed stuffed.

Whenever you get random counts, numbers missing etc, this is always
the cause. The memory unit cant find the "77" or "27" numbers, or
detects the number sequence problem, and keeps searching. As this
device isnt particularly intelligent, it has no "time out" etc and
just turns forever.

Its from the wipers making bad electrical contact with the disc, they
can connect and disconnect as the disc turns (its probably warped very
slightly or something)
I would not advise doing anything at all to the disc as it is gold
plated, The resistors fix it by providing more current through the
wipers (note this is now standard practice in ANY design involving an
IC and a mechanical switch) making sure they will conduct and send the
right signals to the IC

Post by James McClave
Not crazy about the MP3 idea either. Yes, the numbers when scanning did
not read in sequence either. Too bad, from what I know this memory unit
was only used in this model and maybe the R-82?   Jim

Was used in everything ROWE made in solid state prior to R-84

I personally have seen this system in RI-1, R81, R82, R83

I think that the 1975,6 models were available as either solid state
(with memory unit) or electro-mechanical.
I have no idea how many were sold in each type or how popular they
were.
There are few US made solid state ROWE here in Australia prior to
R-81.

Last week I copped a service call from a private owner to service a
"ROWE electronic" that was in a woodgrain cabinet with a lift up lid.
I thought originally it was a kentwood (1979 with central control
computer) and that it would be a simple repair, but to my despair it
had the old board set, and a totally dead memory unit, scanned
indefinitely and showed nothing on the display - (except when you
punched in a selection).

With the cost of an exchange unit, and 2 way international postage
approaching the best part of $400 AU he still seemed keen to get it
fixed for some reason, and didn't want to go with the MP3 option.

Had one R-83 machine come in this week for repair. After I fixed other
faults in the unit, it turned out that it had a "sort of" working
memory unit, however it repeatedly plays "293" over and over
indefinitely after playing the selections that you DO want (until you
hit the "clear memory" button.)

While we had the chance (with a working memory unit in captivity), we
took it apart, monitored the serial interface, drew up timing diagrams
for the serial interface, and the sequence of operation of the IC and
feel more confident now about it being feasible to make a substitute,
since there seems to be enough demand (and dead machines piling up,
taking up room in my workshop). Once I get a few jobs out of the way,
might start on a prototype

[James McClave]

Thanks for all the good info Ken, I may try the resistor method. keep me
in mind if you build a prototype. Thanks, Jim

E-mail us at: ***@webtv.net

[e***@gmail.com]

Post by James McClave
Still looking for one of these. If anyone has a good one, give me a
holler. Thanks.

Hello,
I am with a doubt. My uncle over seas has one of this unit. It broke and a tech when to fix it. He said that he could not repair the part in there and took it with him. He was never seen again.
He is missing the module ( board ) that goes under the Memorec Selection Computer. There are two or three connectors. I have a couple of pictures if that would help.
Does any one has any idea of what part goes in there and if there is any hope in getting that part. I would appreciate any help on this.
Best regards, Ed.

[b***@gmail.com]

Post by e***@gmail.com

Post by James McClave
Still looking for one of these. If anyone has a good one, give me a
holler. Thanks.

Hello,
I am with a doubt. My uncle over seas has one of this unit. It broke and a tech when to fix it. He said that he could not repair the part in there and took it with him. He was never seen again.
He is missing the module ( board ) that goes under the Memorec Selection Computer. There are two or three connectors. I have a couple of pictures if that would help.
Does any one has any idea of what part goes in there and if there is any hope in getting that part. I would appreciate any help on this.
Best regards, Ed.

It sounds like you may be talking about the " Selector Logic Module " and if not that the " Memorec " popularity meter circuit board. If it is the popularity meter module, your machine should be able to play without it.

For the interest of others and to answere what I have read in other posts associated with this thread:

The first generation AMI Electronic Operating System was used in models R80SS up thru R83. It was introduced part way thru the production year of R80 which still employed the electromechanical system ( search unit etc. )

It was designed to make the change from mechanical to electronic as easy and well laid out as possible such as the Mech. Control module put in the same place as the former Mech Control Relay. The encoder and memory unit put in the place that formerly had the search unit. Credit computer on the rear wall similar to where the electro mechanincal credit unit was etc.

There was an earlier electronic credit unit used in the R-74 but as I recall only used in one or two model years.

AMI's first all electronic control system as used in Models R80SS thru R-83 had few problems, was quite reliable for the expected commercial life of the Jukebox which is about 10 to 15 years.

There were a few problems with the custom chip used in the memory module. Sometimes it would only affect the digital display but otherwise the machine would work ok. Some of them as described in this thread wh
en they went bad rendered the machine totally unusable.

AMI Models R-82 and R-83 were a big hit with operators because it was the first cabinet design in many years with no flat surfaces where location patrons could put drinks on it, use it as a table or sit on the program glass. Unfortunately if liquids were spilled on the top of the machine some of it would leak through the hinge.

At one time, quite a few years ago now, I think someone came up with a replacement for the custom chip used in the memory module but I can not recall who it was. Might have been someone in Texas but that is all I can remember.

I still have an R-83 that I bought many years ago, still working ( home private use ) and knowing about the custom chip I bought some extra modules as they were being retired from commercial service. Sorry, at this time I am not selling any of my spares.

You might try durfee coin op I think his website might be www.jukeboxparts.com. He might have some modules parted out of machines. There were two types of memory modules for this system. The earlier one had a separate battery and charger module. The later version which also included " autoplay " should be directly replaceable, had the battery unit built into it.

These were great sounding machines when they are in good working condition.

[John Robertson]

Post by b***@gmail.com

Post by e***@gmail.com

Post by James McClave
Still looking for one of these. If anyone has a good one, give me a
holler. Thanks.

Hello,
I am with a doubt. My uncle over seas has one of this unit. It broke and a tech when to fix it. He said that he could not repair the part in there and took it with him. He was never seen again.
He is missing the module ( board ) that goes under the Memorec Selection Computer. There are two or three connectors. I have a couple of pictures if that would help.
Does any one has any idea of what part goes in there and if there is any hope in getting that part. I would appreciate any help on this.
Best regards, Ed.

It sounds like you may be talking about the " Selector Logic Module " and if not that the " Memorec " popularity meter circuit board. If it is the popularity meter module, your machine should be able to play without it.
The first generation AMI Electronic Operating System was used in models R80SS up thru R83. It was introduced part way thru the production year of R80 which still employed the electromechanical system ( search unit etc. )
It was designed to make the change from mechanical to electronic as easy and well laid out as possible such as the Mech. Control module put in the same place as the former Mech Control Relay. The encoder and memory unit put in the place that formerly had the search unit. Credit computer on the rear wall similar to where the electro mechanincal credit unit was etc.
There was an earlier electronic credit unit used in the R-74 but as I recall only used in one or two model years.
AMI's first all electronic control system as used in Models R80SS thru R-83 had few problems, was quite reliable for the expected commercial life of the Jukebox which is about 10 to 15 years.
There were a few problems with the custom chip used in the memory module. Sometimes it would only affect the digital display but otherwise the machine would work ok. Some of them as described in this thread wh
en they went bad rendered the machine totally unusable.
AMI Models R-82 and R-83 were a big hit with operators because it was the first cabinet design in many years with no flat surfaces where location patrons could put drinks on it, use it as a table or sit on the program glass. Unfortunately if liquids were spilled on the top of the machine some of it would leak through the hinge.
At one time, quite a few years ago now, I think someone came up with a replacement for the custom chip used in the memory module but I can not recall who it was. Might have been someone in Texas but that is all I can remember.

Try Ed at http://www.datasynceng.com - he made some replacement parts
for these machines...

Post by b***@gmail.com
I still have an R-83 that I bought many years ago, still working ( home private use ) and knowing about the custom chip I bought some extra modules as they were being retired from commercial service. Sorry, at this time I am not selling any of my spares.
You might try durfee coin op I think his website might be www.jukeboxparts.com. He might have some modules parted out of machines. There were two types of memory modules for this system. The earlier one had a separate battery and charger module. The later version which also included " autoplay " should be directly replaceable, had the battery unit built into it.
These were great sounding machines when they are in good working condition.

John :-#)#

[b***@gmail.com]

Post by James McClave
Still looking for one of these. If anyone has a good one, give me a
holler. Thanks.