MFOS Weird Sound Generator Questions

Hello,

So I’m currently putting all the components for breadboarding the MFOS WSG into an order with Rapid Electronics here in the UK. I’m not sure about a couple of thing though.

On the website, there are mods for adding Channel A & B Zany Frequency Indicator LEDs. There’s no mention of what kind of LED to use though and I don’t have enough knowledge to work it out. What sort of forward voltage should the LEDs have for the 9V powered WSG…? Or does it not really matter, as it’s all controlled by the value of the resistor that’s in series?

I was thinking of buying some of the Kosmo Minis to help with mounting pots and jacks. The link to the 2x12 pin headers leads to a discontinued product. Maybe I’m just being blind, but there doesn’t appear to be anything similar on the Rapid website. Does anyone have a link to some…?

Turns out my old digital multimeter hasn’t survived being kept in a metal box in my shed for a couple of decades. Can anyone recommend a budget beginner model?

Many thanks,

Boab

(1) Any old cheap LEDs will likely work, you might want to use a different resistor if you don’t like the brightness.

(2) You can buy longer (e.g. 2x40) headers and cut them to length.

(3) Multimeter recommendation

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Thanks for the link to the Multimeter recommendation thread, should of searched for that. Looks like it touches on oscilloscopes too, which is handy.

Thanks!

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The resistor controls the current through the LED, and the 1k resistors used there will limit the current to a range that pretty much any standard LED can handle (roughly (9−2)/1k = 7 mA for a typical red LED, a bit lower for other colors).

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I realised shortly after posting that I’d confused my voltage and current, I’m really out of practice.

Thanks!

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