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How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 3:32 pm
by stripes
I'm troubleshooting a build and I suspect that the switch may be dead... I took it from an old build and when I was soldering on it, one of the lugs started to wiggle out of space a little. I know you can check if a switch is dead but I don't know how. Plz help
Re: How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 5:30 pm
by Moustache_Bash
Set your digital multimeter/vom/whatever to continuity check, in case you don't know what that is, it is the setting that beeps when you touch the probes together. when it beeps that means current can flow between the two paths.
123
456
789
*click* 1 and 4 will have continuity. 2 and 5 will have continuity. 3 and 6 will have continuity.
*click* 7 and 4 will have continuity. 8 and 5 will have continuity. 9 and 6 will have continuity.
Re: How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 5:31 pm
by Moustache_Bash
The click is the switch being stomped, haha.
Re: How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 6:56 pm
by stripes
i have a cheap multimeter from radioshack that doesn't beep... in the ohm setting, does continuity mean that the meter reads -0.00? Also does the pedal need to be powered when i do this?
Re: How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 6:59 pm
by Moustache_Bash
No, the switch doesn't need to be powered.
0 ohms will mean there's a connection. OL (overload) or a very very high resistance reading will indicate an open/no connection.
Re: How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 7:05 pm
by stripes
Okay... and if there are wires soldered to the lugs connected to jacks, the board, etc.. will this effect the reading?
Re: How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 7:10 pm
by Moustache_Bash
If those wires eventually connect together at the same point, yeah. You'll have to use your wits.
3PDT are kind of delicate. When I first started out, I messed up a few of them. You can't really be heating them up excessively.
Re: How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 7:55 pm
by stripes
Yeah.. I've had some problems with them before... and every time I feel like I'm holding the iron on a lug for too long I get all paranoid from that point on. I'm going to take apart all the off-board wiring, test the switch, and try again. i use the diagram from tagboard effects for offboard, but every time i seem to have some kind of problem with grounding or switch wiring. Is there a fool-proof method that you have and always use?
Re: How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 8:51 pm
by Moustache_Bash
It depends on how many ground connections I can get on the board, but I often follow:
http://www.generalguitargadgets.com/pdf ... tb_dcj.pdfI used Beavis' to start out:
http://www.beavisaudio.com/techpages/StompboxWiring/^^^ Thing is with that one, on the output jack he has it graphically wrong which fucked me up over and over till I actually decided to learn what was going on with wiring rather than just following pictures. What's wrong with the beavis one, though, is the output jack is labeled wrong. On a mono jack the inner tab is connected to the sleeve, and the outer tab is the tip. However, it still stands that the sleeve is always grounded and the tip will go to the 3pdt. The tip carries the signal. Sorry if I come off as condescending ever, I don't know how much you know and am just trying to be very detailed.
Also, don't ever get too disheartened. DIYing is a total learning process. It takes forever to get it right, and once you finally do you'll still goof all the time (at least I do).

Re: How to check if a 3PDT is dead?
Posted: Sun Jul 07, 2013 10:36 pm
by stripes
Thanks for the info! I started building about a few months shy of a year ago... not serious, just occasionally for fun. I've made maybe 5 or 6 pedal so far. All from tagboard layouts except for two kits. Oh, and I did a Madbean tremolo.. I think that was the only one that worked on the first try. After continuously running into problems and every time having to look up something new on a forum or ask someone, I think I'm going to start reading up on the stuff and getting an understanding beyond looking at pictures. I want to really know what I'm doing... but every project I get a greater understanding. Thanks again for your help.
