Vintage Synth Repair

You can't just replace the CPU 8049 with another 8049, you need get 
it from roland if still available or from other 101 working CPU.

The fact is that the CPU it's programmed, it has an internal ROM. 
the same processor as Polysix, Juno 60 and other synthesizers.

The other option is to take a working CPU and copy the information 
with a burner capable to read and write 8049 and buy a new 8049 or 
8749. The difference between 8049 and 8749 is that the first one you 
can program it just one time and you can't erase the information. 
The 8749 it's the same version as 8049 but it has a EPROM, that you 
can erase it with a UV Eraser.

VintagePlanet.nl has the original replacement, or you can get from 
ebay 8749 CPU and reprogram.

I did this alredy with Juno 60, Polysix and PG-200.





--- In vintagesynthrepair@yahoogroups.com, "inocencio66" 
<paulo.simoes5@...> wrote:
>
> --- In vintagesynthrepair@yahoogroups.com, Philip <eggwheatis@> 
> wrote:
> >
> > tmp80c49? As far as I know you can use any type of
> > 8049 brand such as a D8049 there are usually some on
> > ebay.
> > 
> > Phil.
> That was a very useful information. Thanks. I had assumed the chip 
had 
> to be of the same exact version/batch as stated in the manual. 
> But, it has to be 80C49. 8049 won´t work and will overheat TR1. 
> Different pinout and voltages (see pin 26): http://www.cpu-
> world.com/info/Pinouts/8049.html . Just for future reference.
> 
> I ordered some 80C49s from ebay since I couldn´t find any at the 
store 
> I had previously mentioned. Should arrive by Tuesday. I will post 
the 
> results later. 
> 
> Paulo.
>