Freebass unit will this give it life

[01012k7]

i wound like to thx paul for helping me out with the tigger for the freebass ( i love this guy and not in a gay way:D)   I have some ideas on how i maybe able to get it going again but will be very basic so input here would help me, if its negative  thats cool will save me time .
Any way ok lets start..

i found my old MidI projects book about 26 years old but has a Midi to cv convert its very basic with 3 knobs and a rotary switch to select the midi channel its main Ic is using a 6402 uart chip which i have as this was the main ic for most of the projects in the book i guess i will maybe have to payout 15 pounds on cases as i have 95% of parts ..

please be understanding i just about know how to wire a plug up

here some pictures of boards and layouts.. ok here the power board first




here the main board

Midi input is pin 1 and pin 2 of CNY17(IC1) Sk2 out is pin 13 4013BE (IC5)


Second board




ok this design is a midi to cv converter which is Logarithmic type will this work?? more info to come i am going to do a wiring schematic of the unit but with pots wire and all boards connected it be a image but i need to go to sleep first..

[Gordonjcp]

That's a pretty old design.  You'd be far better using something like an AVR chips (Arduino board, possibly) and grafting it into the unit where the existing CPU goes.

Again, I'd like to reiterate that I'm constantly on the lookout for a dead Freebase or 383 to experiment with, so I can come up with a handy drop-in replacement ;-)

[Circuitbenders]

Yeah, i'd agree with gordon, that design is pretty much obsolete. Go with something using an AVR or a PIC. This design at Obsolete Technology is pretty good http://obsoletetechnology.wordpress.com/projects/midi-cvgate-converter/

I haven't looked at the control signals on a Freebass for a while, but if i recall correctly you're not going to be able to just wire in an external Midi - CV convertor very easily. I have a feeling that the pitch CV is inverted and nothing like 1V/oct, but i could be remembering that wrong.

Again, I'd like to reiterate that I'm constantly on the lookout for a dead Freebase or 383 to experiment with, so I can come up with a handy drop-in replacement ;-)

After catweazle just blatently stole the broken MB33 i sent him for more or less exactly that purpose, i decided to sit down work out exactly what the common problems are with these things and as a result i haven't come across one i couldn't coax back to life since. Having said that, if i get hold of one thats been completely trashed i'll gladly send it your way. 

[Gordonjcp]

Re catweazle, that's a bit harsh but I don't feel quite so bad about his site disappearing when my Finnish VPS went tango uniform ;-)

I really should have put that in a PM, tactless bastard that I am...

[01012k7]

was not happy with your replys but i know your right i been looking at the Obsolete Technology my self the only reason i put this idea was i have 90% of the parts

Obsolete Technology
only one  problem i have with that build  is the pic programing  which i need to sort out this weekend  i  have the parts for this too as i made a board all ready but have not drilled it yet i also have a spare pic   but  thxs  for the replys i hate it when i am wrong