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So full disclosure - I built the slurpee schematic but on a Veroboard layout. So I used the schematic from madbean and subbed part values and/or swapped in pots where appropriate on the tagboard layout.


http://tagboardeffects.blogspot.com/2013/06/ehx-bassballs.html

With this schematic:

http://www.madbeanpedals.com/EP/schematics/Slurpee.gif


Basically I get a filtered effect - the bass and treble pots work and the distortion switched in and out both work as well.  However, I get no auto-wah type effect.  The response control doesn't seem to do anything.  Here are voltages:

IC1 (1458):
1 - 4.3v
2 - 4.3v
3 - 4.2v
4 - 0v
5 - 0v
6 - 1.9v
7 - 2.1v
8 - 8.6v

IC2 (4558):
1 - 4.4v
2 - 4.3v
3 - 4.3v
4 - 0v
5 - 4.3v
6 - 4.3v
7 - 4.4v
8 - 8.6v

The two transistors in the tone circuit (the bottom two in the layout) measure:

C - 0v
B - 0.65v
E - 0v

The transistor following IC1 and the attack and decay controls (the one off to the right of the board in the layout) measures:

C - 8.6v
B - 8.6v
E - 8v

Any ideas?  I checked over and over again for solder bridges, cap and diode polarity, layout, etc.... I don't know the circuit well enough to understand why I would get the filter effect but no auto-wah.

So it looks like it was something with a broken trace. I had no continuity past the regulator and the cap, so I ran jumpers to the lamp and the next transistor. What's weird is that I had continuity to the lamp at one point and then it vanished. Either way I got it up and running, lamp pulsing (and with a full compliment of 2n5088s - I found a few) and its doing the vibe thing.

I've got a few other problems though. Theres a very low level whine or squeal in the background, but it's the kind I'm going to hope disappears after I trim the leads on the transistors and box it up.

Also, I get no sound when the DPDT is in the other position. But when the board flexes a bit as I switch it the sound cuts in. So I have a feeling it's another trace but I could easily be wrong. Interesting that the only other board I had these kinds of problems with was another thin board. I've done at least 10 other madbean boards that went together without a hitch (normal board thickness).

Thanks all for the help.

Since I had the lamp un-socketed, I took a jumper wire and hooked it into the socket and then connected it directly to the 15v leg on the 7815.  So I measured 15v on the socket of the lamp, but still nothing on the transistors.

This isn't making sense to me.  I should be getting the same voltage on everything connected to the 15v bus here shouldn't I?  Unless there's some continuity issue somewhere? 

I also have the lamp socketed.  I removed the lamp and Q11, Q12, Q13, and Q15 from the sockets and now I get 0v on all of them.  I still get 15v on the LM7815 and the positive side of the C34 cap.  Stumped.

How about just this instead:

https://drive.google.com/file/d/0B-VSm6ER7FEzVTlMcDFCRlVtcEE/view?usp=sharing

https://drive.google.com/file/d/0B-VSm6ER7FEzT0piZG9ydFZNTFk/view?usp=sharing

https://drive.google.com/file/d/0B-VSm6ER7FEzdDg5N2ZVMzB2VEk/view?usp=sharing

Crossing fingers that this works.  Let me know if you can't see the pictures:

Thanks.  Some notes about my build:

1) The power supply that I'm using actually kicks out 19vdc
2) I rely on a stock of 1/2W resistors for a lot of my pedals, so in the pictures you'll see that I have a number of them that are "standing up" on one side.  I'm very careful about making sure that the exposed leads don't touch anywhere and I've looked that over a number of times on this build.  I have six others that I did this weekend using the same process and they all checked out.  But it's obviously a bit crowded in spots. 
3) Q11, Q12, and Q13 are subbed out with 2n5089 instead of 88.  From the voltage readings below, I don't think that this is the source of any problems.  At least not right now anyway. 
4) All of the transistors and the indicator LED are socketed - yes, I know that I put the indicator LED on the wrong side of the board.  I'm a dummy.  They're all standing tall right now because I don't want to trim anything to length until it checks out. 
5) There's no 1054 chip (even though I wasted a socket on it) or any of the other parts for the charge pump as per the build instructions. 

Voltages - I think that they're all within reason, except of course for Q11, Q12, and Q13 not getting any voltage (and hence the lamp not pulsing):

LM7815: 18.8, 0, 14.8
Q1: 2.2, 1.5, 1.1
Q2: 4.7, 2.2, 1.6
Q3: 14.5, 4.7, 4.1
Q4: 18.8, 5.9, 5.6
Q5: 13.8, 5.6, 5.0
Q6: 18.8, 5.9, 5.6
Q7: 13.8, 5.6, 5.0
Q8: 18.8, 5.9, 5.6
Q9: 13.8, 5.6, 5.0
Q10: 18.8, 7.5, 7.0
Q11: basically 0s
Q12: basically 0s
Q13: basically 0s
Q14: 18.8, 0.5, 0

Pictures to follow

So I have a Harbinger One build on my hands (I got one of the thin boards on sale).  I wired it up for 18v power supply and I had to sub in 2n5089s for a couple of the 2n5088s (I ran out, but I'm going to order some more soon... all transistors are socketed). 

I'm getting the audio path through the effect, but the lamp is not pulsing.  I can adjust its brightness with the trimmers just fine, but the brightness never varies.  The speed control does nothing and the on board LED never lights up.  I did some research on the forum and by all accounts this seems to mean that I'm not getting voltage to the 15v side of the equation. 

So I took a look at the schematic and started troubleshooting... and here's where it gets a bit weird... or maybe not, someone who knows more than I do can tell me. 

I started taking voltage readings and found that I was getting 15v coming out of the LM7815 where it's supposed to and next on the one leg of the lamp.  Good.  But then as I followed the trace, I found that I wasn't getting 15v at Q11, Q12, Q15, R38 and R55.  I checked solder joints, etc...  Then I disconnected it from power and decided to test resistance.  Resistance between the LM7815 and the lamp is 0 as expected.  However, it turns out that I'm measuring about 36kohms between the lamp and Q11.  I've isolated it to this part of the trace.  Between Q11 and Q12, Q15, R38, and R55 I get no resistance.  It's just between the lamp and Q11.  The meter quickly gives me a low reading and then slowly starts climbing over the course of a couple of seconds up to about 36kohms. 

I can't figure a good reason for this.  According to the layout it's a straight run from the lamp to Q11 so I don't see why I should get resistance.  Unless there's a flaw in the board?  My thought was to run a jumper along this path on the solder side of the board, but I thought I'd check here first.  It feels like a hassle and something that I'd rather not do unless absolutely necessary.  Let me know what you guys think and thanks in advance. 

So I figured out why I wasn't getting my input signal - I hadn't jumpered the inputs in the effects loop. Duh.  I re-read the document and realized that one. 

However, I was still getting the oscillating signal.  Even though I see no solder bridges or other components making contact, I was able to get it to disappear intermittently by flexing the board a bit (I have one of the thin boards).  I fiddled around with some of the components on the board and I was able to get it to stop by jimmying with Q2 and R34.  Q2 is socketed.

Is there any reason that the oscillating signal would get into the sginal path at this point?  I ask because I'm not convinced that I fixed it for good and I'd like to put it to bed.  Note that the oscillating signal becomes a constant tone when I switch Filter to the other position. 

I wound up socketing the cap anyway and dropped a 47n in.

I finished assembling and hooked it up to my test rig.  I set the pots and trimmers as per the calibration steps.  When I fire it up, I get an oscillating tone and no audio signal.  I get no audio signal no matter where I touch the audio probe to, including directly to the IN clip on the test rig.  When I touch the audio probe to ground I still get the oscillating tone.  I measured about 1Mohm from IN to ground, which would make sense to me with the pulldown resistor.

Any thoughts?  I double and triple checked for solder bridges, diode polarity, electrolytic cap polarity, and IC orientation. 

Posted this in the wrong forum earlier. Apologies.

C1 in the Current Lover is listed as 39n. It's the filter cap right at the input. This can't be a critical value, right? Can I sub in 22n or 47n? Thanks

C1 in the Current Lover is listed as 39n. It's the filter cap right at the input. This can't be a critical value, right? Can I sub in 22n or 47n? Thanks.

Sure, I read the whole thing and figured it out. I just thought it was a little confusing is all. The section you referenced is about the LDRs and the lamp. The lamp is listed in the BOM, but not the LDRs. As someone who uses that BOM/shopping list section to answer the question "do I have all of the stuff I need to build this?", I just think it would be a little more clear to list the recommended LDRs in those sections.

Certainly not a big deal by any stretch. Maybe something to keep in mind for the next revision of the document.

Thanks, and I'm looking forward to building it!

I just wanted to point out that it looks like the 4 LDRs were missed in the BOM and shopping list in the document. Unless I'm missing something of course  (which is always possible, even likely depending on who you ask)

I'm looking at the Slurpee schematic and mods and I have some questions about the differences from the stock circuit. I'll list out all of the differences that I spotted - the firest few I think I understand, the others not so much...

1) R1 is just a pull down resistor not in the stock circuit
2) the led and r25 are just the indicator
3) d2, r26, and c15 are just enhancements or upgrades to the power supply to modernize it (as is the increase of c14 from 10uf to 100uf).
4) c3 is specified as tantalum in the Slurpee - any particular reason?
5) the attack, decay, bass, and treble pots (and additional series resistors associated with them) are mods
6) d1 is 1n914 in the slurpee as opposed to the stock 1n4148? Any reason?
7) d3 and d4 seem to be related to the Mark Hammer mods, although he didn't specify 1n4001 diodes. Why these diodes? And why not the additional change in the resistor value that he recommended?
c5 is 47n stock and 220n in the slurpee. Is this for more low end response?
9) c8 and r14 are 220n and 220k in the slurpee but 1uf and 47k stock. Is 1uf overkill in the stock version?
10) lastly, why is r9 in the slurpee circuit? There's no such resistor in the stock circuit. Does this have something to do with the bass/treble mod?