MUFF WIGGLER Forum Index
 FAQ & Terms of UseFAQ & Terms Of Use   Wiggler RadioMW Radio   Muff Wiggler TwitterTwitter   Support the site @ PatreonPatreon 
 SearchSearch   RegisterSign up   Log inLog in 
WIGGLING 'LITE' IN GUEST MODE

Roland SH-3a LM3216 Replacement
MUFF WIGGLER Forum Index -> Music Tech DIY  
Author Roland SH-3a LM3216 Replacement
home_listening
Hello all,

I'm currently servicing an old Roland SH-3a, the top octave divide down osc has gone bad. For those who aren't aware, it uses a top octave division chip to produce 5 octaves simultaneously.

Anyway, it seems like the chip (LM3216) doing this is kaput - and I don't fancy spending the $25 plus shipping for a direct replacement.

Has anyone has any luck using CMOS to replace these kinds of chips?

Below is a partial schematic:



and here is the pin out:



Any and all help greatly appreciated, Thanks!
home_listening
FWIW; Fixed this.

Ended up using 6 transistor flipflops, daisy chained appropriately. Was fairly simple in the end. CD4xxx series didn't look like it would work without an additional stage for offset which I couldn't be bothered doing.

Brilliant oscillator section actually, the flipflop stages make square waves combine in interesting ways, making all sort of weird staircasey waveforms.
aladan
home_listening wrote:
FWIW; Fixed this.

Ended up using 6 transistor flipflops, daisy chained appropriately. Was fairly simple in the end. CD4xxx series didn't look like it would work without an additional stage for offset which I couldn't be bothered doing.

Brilliant oscillator section actually, the flipflop stages make square waves combine in interesting ways, making all sort of weird staircasey waveforms.


I have some M3216 (both some socket pulls and some desoldered pulls) if you ever find yourself needing more. I think they're the same as LM3216. Sorry I missed your thread first time round :-(

Cheers,
A.
home_listening
Wow, well I'd actually like two if you could spare them. The chips I have are labeled M3216 anyway.

At the end of the day, I'd much prefer an IC to my solution, and I've got another SH-3a that is going to be on the bench in the next few months with similar problems. I'll PM you, thanks
rjd2rjd2
home_listening

hey, i'm about to do the same thing. can you detail the circuit for the 6 transistor flip flops you mentioned? i'd like to have a go at it. thanks.
MUFF WIGGLER Forum Index -> Music Tech DIY  
Page 1 of 1
Powered by phpBB © phpBB Group