Little Gem Wiring Questions

[JT]

I am usually a PCB builder just put the board together for one of these using a RS board . I am using a radio Shack Plastic Project box to house it.......I have a few Newbie questions..please bear  with me as schematic reading is new to me....I am not sure how to wire the board as i am used to using layouts and PCBs and Metal Hammond boxes..In a plastic box how do i wire the grounds?  I Know the jacks in a metal box ground on contact so what if i am using a Plastic box? Do i just make sure all the ground are connected somewhere?  and since i am not using a switch at all how should i wire up the board to the Jacks and power?  This is what i am thinking.....From the input jack tip to the Input cap on the board . I am using a 25 ohm pot on the output  so i am thinking lug 2 goes to the output jack tip. All grounds connect  to the ground point on the board. Is this correct? Thanks in advance for any help!

[aron]

Do i just make sure all the ground are connected somewhere?

Yes, basically that's it. Connect the ground lugs of the two jacks to your ground on the circuit.

and since i am not using a switch at all how should i wire up the board to the Jacks and power?

Yes, input jack tip to input cap on the circuit. Output of circuit to pot etc.. then directly to output jack.

[JT]

Wow i got it right !  :shock:   Thanks  Aron!

[JT]

Well wired her up accordingly , plugged her into a 2x12 and no sound  i am using a Stereo input and mono output jack ..Can this be plugged directly into a 2x12 ?  any thoughts on how to debug or what voltages to check?  I do have 9V on the board in a bunch of spots....... I plugged it into a mini-amp and there was sound but at a lower volume than if i plugged straight into the amp .Thanks for any help or suggestions

[Gary]

First thing to check is pinout of the chip.  Make sure the pin numbers of your chips are going where the pin numbers on the schemtic say.

Second thing to check is the 220uF cap.  Make sure the + side is going to pin 5 of the chip.

Third thing to check is the input and ouput wiring.  Make sure your hot wires (connects to the tip of the cables) do not go to ground anywhere.  Check the pot wiring.  If you look at the pot from the bottom (shaft pointing away from you and lugs pointing down), the 220 cap - lead hooks to the far left lug, the ouput jack hooks to the center lug and the far right lug goes to circuit ground.

This should get you up and running.  Hope you enjoy our little simplified design.  you may be amazed at the volume.  I use the original prototype with a 16 Ohm 2X12 and I get requests to turn it down so the kid can watch cartoons in peace!  You may want to eventually convert this to an adapter fed circuit, as the 386 likes to use batteries pretty quickly.

Best regards,
Gary B.

[JT]

Hey thanks Gary!........looking forward to trying it out..will check over everything you pointed out and will report!