Peizo+Condenser preamp

Inventor · Posted: Sun May 20, 2012 3:36 pm Post subject:

Cool Uncle, how about some photos and sound clips of these harps?

Les

Uncle Krunkus · Posted: Sun May 20, 2012 5:00 pm Post subject:

Yeah, sorry bout that.
I've been meaning to take some photos of stuff for a while.
I'll try to get onto it this week. Laughing

Danno Gee Ray · Joined: Sep 25, 2005 Posts: 1351 Location: Telford, PA USA

how about a set of updated schematics?

Uncle Krunkus · Posted: Mon May 21, 2012 1:00 am Post subject:

Yes, they need to happen soon too.

Uncle Krunkus · Posted: Mon May 21, 2012 3:14 am Post subject:

Here is the latest stripboard layout.
Schem coming soon.

Piezo + Condenser Pre-amp 21-5-12.JPG

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Piezo + Condenser Pre-amp CS 21-5-12.JPG

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Uncle Krunkus · Posted: Mon May 21, 2012 3:29 am Post subject:

Sorry I haven't got any decent image software installed yet.
Here's the schem.

Harp Pre-amp schem 21-5-12.JPG

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Uncle Krunkus · Posted: Mon May 21, 2012 3:34 am Post subject:

I have found that the 500KLog volume pot only has about 20-30 degrees of functional travel. I'm not sure how to do the calculations for the pot ratios. Blend is working quite well, with a slight dip in the centre.

Inventor · Posted: Fri May 25, 2012 10:38 pm Post subject:

I'd try a linear pot there, Uncle. I've not worked with log pots, but I believe they would have a lower practical range.

Les