madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: ct88 on November 20, 2011, 02:45:26 AM

Title: ANOTHER Sunking topic xD
Post by: ct88 on November 20, 2011, 02:45:26 AM
Hello guys, i've just completed another Sunking pedal (clone of a Klon xD?!) but i'm having a lot of trouble :\
checked ICs voltage and seems to be all right, but the pedal lack in volume (@maximum seems to be @ the same lvl as off) and lowering the gain knob the lvl lower too, @minimum is dead off :S

any issues?!

thanks in advance

ct
Title: Re: ANOTHER Sunking topic xD
Post by: jkokura on November 20, 2011, 04:48:10 AM
Yes, that doesn't sound correct. You should take a look at the "rules for getting tech help" thread for some great starter help. If you need more, there's also some tips there on some info we'll need.

Usual problems include:

Wrong or backwards parts.
Incorrect wiring.
Poor soldering.

Ask any questions you need, we're here to help.

Jacob
Title: Re: ANOTHER Sunking topic xD
Post by: joe*211 on November 20, 2011, 06:56:33 PM
Hi, just finished mine this morning.

had a problem with no sound when the effect was engaged (bypass was fine/ I used true bypass)... Voltages were good, the input was getting grounded... Here's the sequence I used to troubleshoot

1- Voltages -OK
2- Use Audio probe = no sound on board input = bad
3- Use voltmeter - check continuity
3A--- Jack to switch - OK
3B--- Switch to board - OK
3C--- In to ground - no resistance = bad
4- I then checked for solder bridges around the jack/switch/input area with a magnifying lens= everything looked fine
5 - I unsoldered the following + used voltmeter to locate where the problem was
5A - Input jack = OK (no short on the jack -- because bypass worked this was almost a given)
5B - Board in = OK (this confirms that the switch was working correctly
5C - measured resistance across R1 (approx 10k) = good
5D - measured resistance across RTB (0) = BAD
5E - lifted RTB - resistance was (approx) 1M = good
6 - I then inspected the area around the board IN with a magnifier... and bingo the board had an manufacturing error... was not the same as the diagram. The ground plane was slightly connecting with the in board in (1st time I've had this type of problem with a madbean board, the board is great quality - this is a very unlikely thing). Instead of being rounded around the board in, it looked like a triangle connecting to the in. I used a small screwdriver to cut the connecting trace around the board in. Bingo. 

The pedal sounds great...
Title: Re: ANOTHER Sunking topic xD
Post by: bigmufffuzzwizz on November 20, 2011, 07:30:39 PM
I second what Jacob said..check solder joints and re-flow the sketchy looking ones. Double check your wiring. If you can't figure it out post some pictures.  :) It sounds like your most of the way there!

Joe- That is one of the most well explained troubleshoots I've read. That's something that would really leave a beginner so frustrated..Congrats!
Title: Re: ANOTHER Sunking topic xD
Post by: ct88 on November 21, 2011, 12:31:38 PM
thanks for the replies guys :D i've checked my board twice but in the same day, i'll try recheck all wiring and values tomorrow, resoldered every connection, and the voltage seems to be okay, i'll post it later for more checkup ;)

ct