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Laurie
Double Platinum Member
Canada
4854 Posts |
 Posted - 08/05/2008 : 23:21:13
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Just want to summarise what we know...
1) The pedal is completely dead - no light, no clean sound, no effected sound.
2) It does not matter how many times the switch is pressed, nothing changes.
3) The power source used is a known-good battery.
4) The wires on the input jack (the lug with the yellow wire) have been repaired and are known good.
Questions:
a) Is it also dead on an adapter? (PSA/ACA preferably)
b) If you plug an input lead into the pedal and do not power it up (no battery or adapter), what is the resistance reading between the lug on the input jack with the yellow wire and the metal pedal housing? It should be "0 ohms" (a short circuit).
c) Again with no power, what is the resistance between the "big" connector on the battery snap (positive) and "terminal 10" on the board? It should be "0 ohms" (a short circuit).
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Kurt
Copper Member
8 Posts |
Posted - 08/06/2008 : 02:46:18
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Laurie, first let me repeat again how much I appreciate your help.
Yes to all you summarized to date, and regarding your new questions:
a) Yes, also dead on an adapter, using a Boss PSA
b) If you plug an input lead into the pedal and do not power it up (no battery or adapter), what is the resistance reading between the lug on the input jack with the yellow wire and the metal pedal housing?
My multimeter is showing 1 ohm, but perhaps it needs to be adjusted.
c) Again with no power, what is the resistance between the "big" connector on the battery snap (positive) and "terminal 10" on the board?
Again showing 1 ohm, but I suspect it is really 0 ohms.
Andrew - yeah, the plugs (assuming you mean guitar cables/patch cables) are good to go. |
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Laurie
Double Platinum Member
Canada
4854 Posts |
Posted - 08/06/2008 : 04:05:02
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1 Ohm is fine - it's connected 
OK... one more initial test (forgot to add it in the last post) - if you plug an input lead into the pedal and do not power it up (no battery or adapter), what is the resistance between the "little" connector on the battery snap (negative) and "terminal 8" on the board? It should be "0 ohms" (a short circuit).
Assuming it is zero ohms...
1) what is the resistance across D4 - positive lead of the multi-meter to the stripe side of D4?
2) What is the resistance between the "stripe" side of D4 and pin 13 of IC2 (the NE570)?
3) What is the resistance between terminal 8 and pin 4 of IC1 (the 4558)
4) Plug a lead into the output and do not power it up (no battery or adapter), what is the resistance between "tip' of the lead you just plugged in and "terminal 5" on the board?
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Edited by - Laurie on 08/06/2008 04:09:11 |
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andrewb
Copper Member
Australia
19 Posts |
Posted - 08/06/2008 : 18:30:09
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i soldered in new red/white/unshielded wires in mine and got it working today
maybe you want to have a look at that? you never know... the plastic melted a lil even for the second i had my iron on it while desoldering...
my LED still wont come on.... but it works so im happy 
good luck with yours Kurt... |
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Kurt
Copper Member
8 Posts |
Posted - 08/07/2008 : 03:51:31
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Laurie,
OK, the last initial test (negative/small battery snap to terminal #8) reads 1 ohm, but I really have to wiggle the battery connector around to get the needle on my multimeter to jump over the right-hand side of the scale.
With (and without, I tried both ways just in case) input lead still in pedal:
resistance across D4 - positive lead of the multi-meter to the stripe side of D4 = 4 ohms
*the resistance between the "stripe" side of D4 and pin 13 of IC2 (the NE570) = 7 ohms
*the resistance between terminal 8 and pin 4 of IC1 (the 4558) = 1 ohm
*the resistance between "tip" of the lead in the output jack and "terminal 5" on the board? - nothing, can't get the needle to budge from the left side of the scale on my multimeter.
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Andrew - congrats on your working pedal!
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Laurie
Double Platinum Member
Canada
4854 Posts |
Posted - 08/07/2008 : 04:46:01
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quote:
Originally posted by Kurt
OK, the last initial test (negative/small battery snap to terminal #8) reads 1 ohm, but I really have to wiggle the battery connector around to get the needle on my multimeter to jump over the right-hand side of the scale.
Sounds like you need a new battery snap for sure. This won't affect the pedal working off the PSA adapter.
quote:
Originally posted by Kurt
*the resistance between "tip" of the lead in the output jack and "terminal 5" on the board? - nothing, can't get the needle to budge from the left side of the scale on my multimeter.
OK... nothing = open circuit. There's at least part of the problem. Trace the wire from the output jack (there is only one) and confirm it goes to "terminal 5". It should be a short circuit from the tip of the output lead to terminal 5 (the board output). This being broken (no reading) means no sound (at all) to the output jack.
It might be the output jack itself - I've had a few recently where the jack looks OK but has cracked underneath and allowed the contact tension to reduce (= very poor contact/no signal).
Doesn't explain why the LED doesn't light, but lets tackle that later.
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Edited by - Laurie on 08/07/2008 05:04:54 |
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Kurt
Copper Member
8 Posts |
Posted - 08/08/2008 : 22:12:00
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OK, so I went back and checked the resistance again between the output tip and terminal #5, and this time got 1 ohm. So thinking that was another dead end, I decided to replace the battery connector (happened to have a few new ones from another pedal project) and...
IT WORKS!!! SUCCESS!!!
Working just fine now, LED lit up nice and bright, all is good. Can't thank you guys enough for your help troubleshooting, you have made a new fan of this site forever.
I will be sticking around, having just picked up a SD-1 that might need some tweaking.
Thanks again Laurie and everybody else - you rock!
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Laurie
Double Platinum Member
Canada
4854 Posts |
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andrewb
Copper Member
Australia
19 Posts |
Posted - 08/10/2008 : 11:10:13
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good to hear kurt  |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 08/10/2008 : 16:18:54
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Hi Kurt
That's really great news...
Regards Dr. Bob |
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Topic |
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another (!!) dead DM-2
