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Andy40
02-07-2017, 04:50 AM
This is where it starts. I've proved I can etch a board. Here I just bought one for about 9 bucks.https://uploads.tapatalk-cdn.com/20170701/a0d8b29758ca1679563305284e10d5dd.jpg
Instructions, check!
https://uploads.tapatalk-cdn.com/20170701/281b141bf0e0a301bea3a41b004c0144.jpg

Andy40
02-07-2017, 04:55 AM
Okay. Question for the pros. Still getting my head around caps. Greenbean instructions say I need 100n film caps. Does that translate to 0.1uf? If so, for the 120n film cap do I translate that to 0.12uf? Because I've only got 0.1uf caps

DrNomis_44
02-07-2017, 05:54 AM
Okay. Question for the pros. Still getting my head around caps. Greenbean instructions say I need 100n film caps. Does that translate to 0.1uf? If so, for the 120n film cap do I translate that to 0.12uf? Because I've only got 0.1uf caps


The shortest answer I can give you to both questions is....yes.

However, I'm going to elaborate on it a bit, a 100nF cap is equivalent to a .1uF cap, and a 120nF cap is equivalent to a .12uF cap, now, if you have a circuit that you want to build that needs a .12uF cap, or a 120nF cap and you only have some .1uF or 100nF caps, you can quite easily substitute a .1uF/100nF for a .12uF/120nF and the circuit should still operate perfectly, you can also substitute a .15uF/150nF cap for the .12uF/120nF too with no problem, most electronic circuits are actually not that critical.


The only thing you need to be mindful of is that the DC working voltage of the substitute cap is equal to, or greater, than the DC working voltage of the originally specified cap, so say the circuit needs a .12uF/50V cap and you happen to have a .15uF/100V cap, it will be perfectly okay to use it as a substitute.

Andy40
02-07-2017, 06:16 AM
Thanks Doc! that was a great explanation.

DrNomis_44
02-07-2017, 06:26 AM
No worries mate, there's another thing you can do if you're building a circuit and it calls for a cap value that you don't have, you can make up the cap value by putting two smaller value caps in parallel with each other for example, if you need a .1uF cap and you only have two .047uF caps, you can put them in parallel to make one .094uF cap which is close enough in value to a .1uF cap and will work fine.

Or, you can put two .22uF caps in series and you will get a .11uF cap, which is also close enough in value to a .1uF cap and should also work fine.

mjg
02-07-2017, 06:35 AM
As Doc says, it won't make much difference to substitute a 100nf for a 120nf.

In this particular case, if it is c5 you are talking about, that one is controlling the tone of the 'Fat' switch. So using a 100nf is fine, you will just not have quite as much change when you flick the Fat switch. You could also try a 150nf or 200nf in there too, to see what tone you like best.

WeirdBits
02-07-2017, 11:07 AM
Also, if your multimeter has the appropriate function, test the value of your caps before you use them. That way you start with a known entity and can swap it for another if it's a little too far out of spec and/or not giving the sound you expect.

DrNomis_44
02-07-2017, 11:23 AM
Most caps these days usually have a tolerance spec of anything from +/- 10-20% of the marked value on the cap.

Andy40
08-07-2017, 12:35 PM
Genius!https://uploads.tapatalk-cdn.com/20170708/73e01835e832c627eef20be4a9b66a21.jpg

Andy40
09-07-2017, 05:41 AM
removed post.....I read the schematic...its obvious:o

Andy40
09-07-2017, 08:45 AM
Arrrrggg. Nothing but static and squeal. I gotta put it down as I'm outta time. See if you can spot the problem. https://uploads.tapatalk-cdn.com/20170709/cf0776bede5c0bca9c36debbf2809b2f.jpg

Simon Barden
09-07-2017, 07:44 PM
I can see two capacitors that I think are the wrong value, C1 and C4. 4n7 (4.7nF) installed instead of 47nF.

WeirdBits
09-07-2017, 09:08 PM
According to the values written on the mag board, yep.

Simon Barden
10-07-2017, 06:40 AM
Apart from that, testing a gain pedal out of its grounded case might let a lot of noise pick-up in.

Also, if you've bought the parts yourself, double check that all the capacitor voltage ratings are 25v or higher. I checked over half of the resistor ratings and they looked OK, but you might as well double-check those.

However... looking further at the greenbean website diagram, I think I know what the problem is. The input jack has no direct ground connection and is reliant on the casing connecting the ground through from the output jack. Not surprising you just get noise as there's no complete circuit and the guitar is just acting like a noise aerial! Try linking the jack socket grounds together when testing without a case. You'll probably need to replace C1 and C4 to get the sound right but they probably won't stop it working.

Maddogm
10-07-2017, 11:18 AM
are some of those resistor solders (towards the bottom right) a bit dry? hard to be sure without seeing the other side of the pcb though

Andy40
10-07-2017, 12:02 PM
Thanks guys, I pulled those caps and replaced them. There was something wrong with how i wired that switch, it was a bit more than just the earthing issue.
Tested on the breadboard today with the new caps and bypassed the switch and she worked a charm!

This circuit really rocks!

Andy40
17-07-2017, 04:33 PM
Sufficiently rocked and boxed
https://uploads.tapatalk-cdn.com/20170717/36f6dd229623f24cf2a114efa4687b74.jpghttps://uploads.tapatalk-cdn.com/20170717/d7786ac6c96bedb3d47fefe2698df7b0.jpg
Time to decorate

Dedman
17-07-2017, 05:40 PM
congrats! No idea what any of the afore mentioned posts were about but I take it you got it working!