Here are some CHA47 layouts.

I don't think he's done it yet. He is just wondering if it is possible and if someone might be able to do it.

another view:

Here are a couple of pictures of the finished layout. I wouldn't usually post it, but I just wanted to show that the 4.7 KOhm resistors can straddle the jumpers near the ICs without a problem (which I was worried about myself.) Plus, it's just nice to see the actual thing:

I posted a photoshop layout of this protoboard for download, in case you want to use it. It's near the bottom of the page in the link. You can just use layers and slide the parts around to figure out how you want your layout. Link

Quote: First off, realize that this circuit needs to stay powered up all the time Oh yeah. That whole "standby mode" thing. I guess you could rig some mechanical connection to close when you plug the phones in, but that might be kludgy unless it was designed right. Possible, though.

Expect your gain to be pretty low. I had to adjust mine several times because I wanted to use more of the volume pot before it got very loud. I think that I went with a gain of about 2, maybe 3. As far as the output resistors, I don't know how it sounded without them, because I never tried. I...

That's interesting. Couldn't you also set it up so that the amp doesn't turn on until you plug in your headphones? To turn it off, you just unplug the headphones. That would be cool for a really small design or even if you don't want to fool with an on/off switch.

I hooked up a 10K pot and tested the levels. It's distorted throughout the range, but only at about 1/4 of a turn does it start to splat and cut out for half a second after every splat. As far as power goes. I think that a split supply woks best: Quote: And not even use the V-...

This is from the datasheet. - I couldn't find .05 uF so I'm using .1 uF. - RadioCrap was out of 220 uF so I'm using 2x100uF in parallel. I also tried a 470 uF, but same effect. - I don't have a pot hooked up, but I tried with and without 10K resistor, but no difference (well, louder w/out it...

This is the power supply with a 9-volt with the ground connected to everything else (input gnd, output gnd). I also tried the basic cmoy power supply, but that didn't seem to work either, so I'm trying this simple design.

It does exactly the same thing with headphones. Does that make a difference?

Thanks for your replies, I've now started testing this project with a breadboard and jumpers. Well, I'm fooling with the LM386 and I'm trying the design on the datasheet for the "amplifier with gain = 20." I. Problem: I can get very faint sounds, but if there is a bass or drum kick, it...

You should just have wires that hang out of your hammond. The wires should be bare throughout the length and they should have no connectors on the end. That way you can just carefully lay the wires against the 9volt terminals. Replacement is just a matter of sweeping the old batteries out of the...

Okay. For my next trick, I'm doing the CHA47 (or is it a CA47, or maybe it's an Apheared 47 now, could it be just A47?) Here is the layout. Let me know if there are any errors or if it can be done better. I left out the CS cap (in relation to the Buf634) because I couldn't hear any...