Trouble with Synare 3 diy kit from Helensson -I need Help/advise.

Thread Starter

riddimshakk

Joined Jan 19, 2013
4
Hello Community. This is my first post here & the reason i came here.
I am working on a d.i.y pcb kit from 'Helensson'...
(http://www.helensson.com/synare-3-kit.html) .....But having trouble.

It is the 'Synare 3 analogue drum synth. Very nice too !
I have just finished soldering my second board (The first one failed & so i tried again)
It's a well soldered board this time & i'm pleased with the solder quality & satisfied that all components are the right way around etc..
The trouble is this... When i supply power to the board & switch on the oscillators all i get is a constant drone & only with the resonance turned right up. So that's 'no off' just continuous sound.
I have seen this issue raised on annother forum but i cannot get on there to ask for help (They won't send me the varification email to complete membership)...Here's a link... http://electro-music.com/forum/viewtopic.php?p=375436
It's a short thread & does not conclude.
Anyway ,i'm here now & looking for help. I am also trying to contact the guy who supplies the kit.
Is there anyone out there who is familiar with this kit ?
I'll be looking in here in case of any help. Thankyou.
 

Thread Starter

riddimshakk

Joined Jan 19, 2013
4
OK, thanks for replying. Well, it's supposed to be activated by its trigger. In this case, a piezo sensor but instead there is no sound unless i raise the resonance pot (filter section) fully up.
So...when the volume is turned up & the resonance (filter section) is also up, if i switch either of the oscillators on i then get sound output but self activated & continuous rather than triggered. It won't switch off, just constant.
When it is sounding i get the following functions... Volume pot (although crackly), osc 1 tune, osc 2 tune. The switches seem to select the correct function & they switch off too.
The sound is not a flat drone. Sounds as if it's being modulated slowly (possibly by the filter) Slowly raising & falling like eithe a sine or triangle shape.
I can hear no audible changes when i turn any other pots apart from some faint interference can be heard while turning one or two of the pots.

It's odd really that the sound is like listening to two detuned saws but with the res right up. Normally that would make any other oscillator scream.Having said that, the rest of the filter functions are not doing anything.

I am still communicating with the supplier & he is trying to help.I've sent him photo's of my boards & he's confirmed it looks ok.

I'm determined to get to the bottom of this because it will be such a nice sounding synth when it works. If i find a solution i will post my findings here for any other folks to refer to.
I think that the Clacktronics schematic differs here & there from this kit. In fact, i think that this kit differs from it's original form here & there too. I;m just learning to read schematics.....Bit of an amateur, practical but amateur !
 
Last edited:

THE_RB

Joined Feb 11, 2008
5,438
It sounds like the drum circuit is not triggering at all. What you hear by cranking the resonance right up is probably some artifacts caused by the resonance oscillators.

You should check the parts values and soldering etc around the input circuit (there is probably an opamp IC that picks up the signal from the piezo drum sensor).

Also if you post a photo of the PCB and your soldering etc it will help clear up if all the soldering is tip top and all the connections are ok.
 

Thread Starter

riddimshakk

Joined Jan 19, 2013
4
Here are some pictures of the board. Regarding the soldering, i was very careful & i checked all joints at each stage with a magnifying glass before moving on to the next part. I believe that the soldering is all good.
The picture quality is a bit blurry because my camera is not so good at close up stuff.

06012013(001).jpg

06012013(002).jpg

Photo0439.jpg

The picture of the board without wiring is the first one i did .I've just put it here for reference, all components are in the same place as the new board.

I suspected a broken wire at the main volume pot & so changed the harness. That stopped the crackling a bit. Interestingly, the volume pot behaves like this...Turn it up a quarter turn - nothing in that section ,the next quarter gives sound output, the final two quarters give no sound output.

I supplied 17v dc to the board via a regulated power supply & have measured +12 v & +6v at points Q15 & Q16 as advised in the manual.
View attachment manual.pdf

I even changed the batteries in my meter to be sure it was running clearly......Still scratching my head but not making any changes to the board.
 

THE_RB

Joined Feb 11, 2008
5,438
Thank you for taking the time to post those photos! For future reference if your camera has a "macro" setting (looks like a little flower icon) thatwill help a lot taking close up photos of solder joints etc.

Re the fault, I feel for you. That is a very complex kit, and it's a real bummer doing so much work and then it has a fault.

However it's a real hard thing to diagnose from a distance! Your photos show you are methodical and careful and your soldering looks quite neat. :)

At this point all you can really do is hypothesise what things might cause the fault, and then investigate those things further;
1. bad solder joints (check with magnifier).
2. incorrect parts placement (check cross reference with instructions, also resistor values/colours!).
3. wrong parts orientation (chips backward, transistors backward or wrong legs pinout).
4. chips now damaged due to some early fault condition (replace chips as a set)
5. wrong wiring to pots and switches (careful checking)
6. PCB fault (magnifier check entire PCB for shorts or broken tracks)

After those, if you have access to a 'scope or some other equipment you could analyse the operation as blocks, and try to test or evaluate each block. Like I said before the input block should detect the small signal from the pieze transducer and then amplify it to become a reliable trigger pulse for the "drum".

Other blocks are things like oscillators, which either run all the time or only after they are triggered. Hopefully the schematic shows some areas as blocks which will help to test the blocks.

If you don't have test equipment, don't despair, 99% of kits that don't work first off are due to bad wiring, or things like wrong parts placement, especially resistor colour codes and resistors are in the wrong places.

One thing that can be nasty is if the transistors supplied have a different pinout than the one shown on the PCB. You can check that by downloading the transistor datasheet and checking the real transistor pinout against the one on the PCB. Also some multimeters have a transistor tester that will help to determine pinout.

Good luck with the project, it might take a lot of time and hard work to find the fault but then you will probably find it was something really simple. ;)
 

Thread Starter

riddimshakk

Joined Jan 19, 2013
4
Thankyou for taking the time .Good to know there are other humans outside the laptop !
It'll be slow progress but then hey, it's a learning curve.
Again, if i find any solutions i'll post them here.
 

unaboomer

Joined Aug 4, 2013
1
I know this is an old thread, but for anyone seeking help-

I had a client bring me one of these to build for them and all the CA3080s were either not working or fake. Replacing all the OTAs fixed it. It had crazy filter issues like you have.

Then again there are a lot of other things that can cause what you described, but Id start there.

Also, you might want to make up your own wiring. The stuff supplied with it is weak and very thin. I remember thinking "if this is someone's first build, this is gonna frustrate the hell out of them!"

The seller has a serious lack of support with these kits. My customer lost his supplied USB key and the seller didnt even respond to offer help or even tell me to bug off. Thankfully Ive worked on these before and the circuit is very simple.

If youre retrofitting an old one, you'd might as well just fix it. The kit is just going to add grief.
 

Wendy

Joined Mar 24, 2008
23,415
Welcome to AAC.

Congratulations, you have practiced the arcane art of necromancy, the revival of a long dead thread. Likely the OP (Original Poster) has solved his problem, or thrown it away, or something.
 
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