SOLVED one bad SMR4 voicecard/AVR

Bought one of the complete SMR4 Ambika kits. Very nice!

Unfortunately the very last voicecard I put in as voice six didn’t light up. I metered a couple of things and noticed PIN 14 on the AVR was at about 5V on all the cards except the bad one where it was at 0.2V.

I metered a couple of other things and checked all over the board for shorts. Seemed fine so I just swapped AVRs with one of the working cards. The AVR from the working card made the bad card work.

I’m not set up for troubleshooting the AVR right now (no CRO or ISP). There’s no replacement SMR4 AVR in the MI Store that I can see. Any help anyone ? :slight_smile:

PS Five-voice Ambika is my favourite synth right now!

Have you tried doing the firmware upgrade procedure to the faulty voicecard?

Didn’t even know about it. The ISP headers made me think you couldn’t do that even though it occured it would be an awesome feature. I’ll try when I get home.

Awesome feature!

I tried it.

I get “upgrade” for every card except the one that isn’t lit which says “install”.

I tried upgrade on one of the good cards just to test a good one and it did the programming and the light show.

When I select “install” on the bad card all the voice cards turn off LEDs for less than a second then come back on. Didn’t look like the programming happened. Bad AVR card light still off.

I swapped the AVR from the bad card with one of the good cards. The bad card becomes the good card. The good becomes the bad. Then I tried “upgrade” and “install” and the functionality follows the AVR.

Pretty convinced that one AVR is the only bad part now.

Send me a private message with your address and I’ll send you a replacement…

That should totally solve it :slight_smile: