Utility LFO Help

LetterBeacon · Joined: Mar 18, 2008 Posts: 454 Location: London, UK

I've finally managed to hook everything up on my Utility LFO, but unfortunately I have a few problems. Both LFO output the same waveform out of all the outputs. I have attached a picture of my oscilloscope.

The speed pot appears to work as the LEDs and the wave on the oscilloscope go faster, but nothing else does. The range mod doesn't seem to have any effect.

The wiring seems to be ok, and the ICs are all orientated the correct way. I've run out of ideas so if anyone can help that would be greatly appreciated!

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The output of the LFO.

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LetterBeacon · Joined: Mar 18, 2008 Posts: 454 Location: London, UK

I'm an idiot. I forgot to connect anything to the GND pads on the PCB. Whoops! It all works now apart from the Range mod but I'm sure that's just a wiring problem.

LetterBeacon · Joined: Mar 18, 2008 Posts: 454 Location: London, UK

I'm still having problems with the range switch. Here's a slightly grainy photo of the way I've got the capacitors hooked up to the on-off-on range switch. Can someone verify that what I've done here is the same as what's in the diagram?

Posted Image, might have been reduced in size. Click Image to view fullscreen.

Posted Image, might have been reduced in size. Click Image to view fullscreen.

The top cap is 470n, the middle one is 4.7n and the bottom one is 47n.

Here's the diagram:
http://modular.fonik.de/files/CGS_LFO_mod.jpg

blue hell · Posted: Mon Oct 05, 2009 11:19 am Post subject:

Looks like blue wire should go to middle contact on switch?

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LetterBeacon · Joined: Mar 18, 2008 Posts: 454 Location: London, UK

Ha! That was it - thank you very much!

blue hell · Posted: Mon Oct 05, 2009 1:24 pm Post subject:

You're welcome.