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I have a bunch, 8 pin DINs.  Lemme know if you can't find one reasonably priced.

I used some GL5537 LDRs I got off eBay, tested the lot and chose four that has the closest values.  I've built two Doubel Gangers with them and they both sound great.

Perhaps others will also share their experience with their chosen LDRs.

Thanks- Great to feel the strong support around here!

Wow- I really like the color and design you did.  Quite impressive!

I'm starting to build one of these and wondering how you did the artwork layout.  Might you be able to point me to an example or template?  Especially for the waveshape and multipliers- seems like this is tricker than other designs I've done.

Wow- I really like the color and design you did.  Quite impressive!

I'm starting to build one of these and wondering how you did the artwork layout.  Might you be able to point me to an example or template?  Especially for the waveshape and multipliers- seems like this is tricker than other designs I've done.

Exactly, solder bridge underneath some flux residue I couldn't see.  I'm not 100% sure where it was but I suspect it was between R26 and R27.  After looking at the layout diagram again, this would make sense given the low voltages I was reading on IC1 pins 5-9.

Flick us a photo of both sides?

Derp... scrub a dub dub with some lacquer thinner and a toothbrush then alcohol.  It's working fine now!

Amazing how much tiny crud comes off with a good cleaning.  I'm surprised I missed it after inspecting with my USB microscope.  Need to make sure to add "cleaning" to my list of debug steps when I get stuck. 

Back to building, and thanks again!

Hello great folks of Madbean!  I've been lurking awhile and with all the great knowledge on this forum, have built up several Madbean projects.  Thanks to you all, I've learned a TON over the last year from basic electronics, to enclosure design and finishes. 

Currently, I'm stumped with my Doppelgagner build and really hoping you guys can help me sort it out.  (this is the v2.1d board).

I've been trying to debug the problem through the usual means (recheck component values, reflow solder joints, check for bridges/shorts) but no luck.  I've also quadruple checked the wiring to the 3PDT switches as well as checked the switches themselves.  I'm using B2K for the Spans.

From looking at some prior posts such as this one (http://www.madbeanpedals.com/forum/index.php?topic=17032.15) I can see I have some voltage issues on IC1 (pins 5-9), but I can't find the root cause.  I've swapped out IC1 with another (known working) TL074CN but that did not help.   

Some other odd behavior that may be a clue is that when I first plug in the 9V, D9, D10 and the HF LED light up briefly, but then fade out.  If I short IC pins 4/5 or 5/6 they also light up.

Here are my voltages:

Source: 9.41V 
IC1 (TL074):
1-3: 4.33 
4: 8.66
5: 1.6
6: 1.56
7: 1.56
8: 1.6 
9: 1.6
10: 1.6
11: 0 
12: 4-4.8
13: 4.2-4.8 
14: 3.5-5.2

IC2 (TL072)
1: 3.7-3.9
2: 4.0-4.2
3: 4.2-4.7
4: 0 
5: 4.2-4.7 
6: 4.2-4.7
7: 4.2-4.7 
8: 8.66

IC3 (TL074)
1-3:4.1 
4: 8.1 
5: 4.1 
6: 4.2 
7: 4.1 
8: 4.1 
9: 4.2 
10: 4.1 
11: 0 
12: 4.1 
13: 4.6 
14: 4.5 

IC4 (TL072)
1: 4.1 
2: 4.1
3: 3.3 
4: 0 
5: 4.1 
6: 4.1 
7: 4.2 
8: 8.1 

Any input is greatly appreciated!

Machined aluminum, an object of beauty, makes you feel all warm a fuzzy. Reasonably priced to boot.

dave

I also have the Engineer solder sucker and agree that it works well, being small and powerful.  The silicon tube tip works great to get a seal on the component/pad and has a good spring/suction force for a small unit.

The thing I don't get about it is it the solder it pulls gets stuck in the silicon tubing and doesn't make it into the chamber (perhaps the silicon tubing cools it down too quickly?).  Therefore, the tubing needs to be cleared out manually after each use, often requiring a dental pick or other implement.

I'm fortunate to have recently picked up a used Hakko FR-300 from Pryde which is great for tasks to desolder multiple components in one go, or other tough removal tasks.