e-licktronic Forum

Sooo... After getting my triggering issues fixed ( which turned out to be because I'd soldered in Q32 the wrong way round ) I find that my accent has no effect. From what I can understand, the accent trigger in attenuated and then then multiplied/added with the quarter note pulse at Q32, yes?

So, from looking at the schematic, I should have the triggered accent step pulse at the collector of Q33,and the attenuated version at the collector of Q34? I'm at work right now so I'll have to check that when I get home.

I'm wondering whether Q32 got damaged by being in backwards, or when I desoldered and resoldered it in the right way..

FIXED!

After tinkering around trying to measure the resistance of the resistor where the accent trigger comes in it seems to now be working - I think possibly some resistor leads had got squashed against each other...

So.. I think that means.... BUILD COMPLETE!

Sorry to hijack this post, but i'm having an issue with my accent.
I'm building all the voices and testing them with an external triggen signal (Boss DR110)
At some point i noticed i didn't have to put 5v on the common trig rail to get my voices triggered from the individual trigger points. I found i have 5v on my common trig rail. So something is probably wrong with my accent section as it supplies 5v to the common trig rail on a trigger input.

One or more of the transistors of the accent is likely burned, but which one and how best to debug this, any help is appreciated.
(I tried to test the transistors in circuit with diode test on my mm but i can't find anything particularly wrong, but i'm not sure what to look for, there's no obvious shorts as far as i can see)

Could it be any other part from another voice failing and putting 5v on the common trig? (trig inputs maybe)

You're using the schematics, yeah?

Check at R92, this is where the quarter note trigger comes from the CPU (I made an audio probe rather that using a scope), then check at the base of Q31 (after this trigger signal has gone through a few gates) Still good? A few people had troubles with their 4011 chips, so if something's wrong at this stage, you might want to look at replacing that. At this point, you'll wish you'd put it into a socket..

Buuut if that's fine then check the base at Q32.. Work your way round I guess.. Good luck!

Thx for your info. I haven't built the sequencer yet, but i'll test with external trigger.
I want to try to fix this before finishing the the rest of the voices (only CY,CB,OH,CH to go) to avoid damage.
Just to add to my previous description: i'm getting 5v dc from the common trig without any pulse at the accent or trig inputs.

I found out Q31 was shorted so i replaced it. The contant 5v is gone from the common trig rail now, so hopefully it's all good now.
I didn't dare to use external trigger again, i'll wait till after the sequencer is finished and hope it'll work.

callmefengzi wrote:At this point, you'll wish you'd put it into a socket..

i socketed all the IC's not the transistors though, i just cut it loose

deejayraoul wrote:

callmefengzi wrote:At this point, you'll wish you'd put it into a socket..

i socketed all the IC's not the transistors though, i just cut it loose

Hah, the guy that said that appears to be some sort of spambot - he just copied part of my response and added some spammy link

Glad you got it sorted though.

Reported the post, spam indeed