Post your Silicon Chip/Jaycar kit questions here!

No problem at all.
My own Jaycar/SC is currently being modded and seriously "pimped" so my readings may differ from yours.

It's nearly finished, so if you can wait a week, I'll take readings then for you.

That said, if you are in a hurry, mine is making noises and you are welcome to test your chip in my circuit.
Am quite sure Jason could pass my contact details on if you want to try this. Thats fine by me.
The more Theremin players in London the better, actually the more Theremin players the better!

Jason, did you get to think about having the Pimp my Theremin gallery? If so can I send some photos?


Regards

MarkT

It works now:-) I replaced that chip and it sprung into life. After a few days of fiddling think we'll have a go at some mods probably. Perhaps we should learn to play it first, for now we've just been trying to make some Sci-Fi sound effects...

Thanks for the help. Hope your mods work out.

Mark

Hooray! Another Theremin is born!
Fantastic news that you got it to work now.

Good idea to play about with it first before adding mods.

Regarding the mods too, read everything and then read it again. One drawback with with this model is the size of the case, movement around the pitch rod can interfere with the volume, but you'll find this out yourself.

That said, the kit is a good place to start with electronics and Theremins.

Enjoy your new instrument.

MarkT

Hi!

I'm from Finland and I'd like to buy one of these Jaycar theremin kits. Does anyone here know how I can order it directly here? Or do I have to order it to UK and then ship to Finland? In their website there are only options to ship to UK or somewhere else, but no European shipping possibility. Which shipping possibility do I choose? Please help me.

-Sami

Hi Sami

The kits actually come from Australia, but you probably know that.
I would suggest sending them an email asking for a price to ship to Finland. They can only say no.

If they do say no and you're still interested, I'll order one for you and send it on.

There is also a MK2 version from SC/Jaycar, think its been discontinued but is still around in the hobby shops of Australia for now. Again I can get one sent to you.
How does that sound?

Regards

MarkT

Hi! Thank you for the offer Mark. My friends friend sent me the kit and it arrived today. I haven't been on the computer for a week because it was in repair.

But now i got the kit and I'm starting to build it tomorrow. Should I add all the Max's mods or just some of them? I went to a local electronics shop to buy the parts for all the mods. Anyone know how big cabinet should I make for it to have space to play properly?

Now I'm going sleep and start the building tomorrow.

-Sami

Has anyone got good picture of the modified ready (with the components on it) circuit board? It would be nice. Send me pictures by e-mail qahwi@hotmail.com. I would appreciate it.

Hi all. Finally got a chance to put together the Jaycar theremin kit I bought a few months ago. All wired up - NO SOUND!

I'm decent with a soldering iron, having wired up a number of guitars and even swapped components on PCBs before, but I'm not that expert on circuitry. So, while I think I did a good job on the board, maybe there's something wrong I can't see. Judging from other comments here, it sounds like there might be a short circuit somewhere, but I can't find anything.

On taking the PCB out of the kitbox I discovered I can get sound IF I touch certain parts of the circuit, especially the connection between the center lug of VR1 and IC3. IF I'm touching this, the sound becomes loud, but the thing still doesn't seem very tunable. There's a tiny range on T3 where the sound is generated, and once it's there, turning the other adjustments (T1, T2, T4, VR2) don't seem to do much.

I don't have a multimeter, and I'm not sure what the numbering sequence is for the IC pins even if I had one, so I have no idea on the voltages.

So, does anyone have any ideas what I might be doing wrong? I'm starting to feel like an idiot, or if this is far more complicated than it's advertized to be.

I really appreciate any and all advice!

Mel

Mel

So you are at least getting power to the curcuit, thats good.
Am currently in an email conversation with Sami from Finland who is also getting no sound, but will, so don't give up!

Its probably a good idea to invest in a multimeter at this point, you can't do much more without one and setting up the thing will require it. It'll come in handy for your next project too.

ICs/chips ALWAYS have the same pinout, that is, at one end, there is a notch, look at the chip so that the notch is at the top.
On the left hand side, the top pin is number 1, the one underneath it is 2 and the one underneath that is 3 and so on. When you have run out of pins on the left, the numbering continues from the bottom of the right hand side
to the top. Google will tell you this.

Have you read and followed the setting up section of the instructions?


Regards

MarkT

MarkT,

Thank you very much for your help. I got a multimeter, and using the 20VDC setting, I get the following readings: from T2 case to IC2 pin 8: 2.82V. T2 case to IC3 pin 6: 2.86V. It's consistent regardless which transformer coil case I measure from. Also, I did measure 5.69V on IC3 pin 7, the pin that's connected to the VR1 middle leg.

So, what should I be looking for next to isolate the problem?

I really appreciate your help!

Mel