Cascadia Issues

[cajone5]

So I got this built up and it was relatively straightforward but I'm having a few issues. The diodes are all smallbear 1n695's as recommended and no substitutions except an added switch to parallel a resistor with R5 to make the second switch boost more based on some comments in the group buy thread.  The center setting eliminates the extra resistor and all the issues occur regardless of the setting.

1. The DPDT on-on "Bright" switch does not work in the "right" position.  It occasionally has a very faint flubby sound but it quickly fades and isn't really repeatable. Checked continuity on this switch and it appears to be working correctly.

2. The treble control appears to work in revers and has limited range.  It seems like it cuts treble when turned clockwise which seems wrong based on the way the other two controls work.

3. The overall sound of the pedal is very flubby and somewhat gated.  Definitely not as described in many build reports.

So that said, I am guessing I made an error.  Can anyone help diagnose it?  Without IC's other than the charge pump, I'm not sure where voltages would be helpful.  The charge pump IC has the following voltages

Power Jack: 9.35V

IC1:
1 - 1.332
2 - 4.116
3 - 0.002
4 - (-)4.925
5 - 0
6 - 2.522
7 - 1.441
8 - 9.29

Pics of it in the box... I'll pull it out if I need to, of course but hoping for a diagnosis without that.  Guessing it's a bad solder joint since gordo has similar issues...http://www.madbeanpedals.com/forum/index.php?topic=26726.15

[jubal81]

Thanks for posting voltages.

Pin 5 is the negative output, which should be more like -8.6v or something in that territory. Your electro caps look like they're oriented correctly, but I can't see the ones on the footswitch board.

Nothing else is jumping out.

I'd recommend double checking the orientation on the charge pump chip and the electro caps on the footswitch PCB and taking another look at solder joints. Also, check for shorts across the 100uf caps on the footswitch board.

[jubal81]

Also, R5 is the resistor in the far bottom left of the pic (horizontal). Wiring could connect there, but looks like it goes straight up from the switch to possibly the wrong resistor?

[cajone5]

Thanks for posting voltages.

Pin 5 is the negative output, which should be more like -8.6v or something in that territory. Your electro caps look like they're oriented correctly, but I can't see the ones on the footswitch board.

Nothing else is jumping out.

I'd recommend double checking the orientation on the charge pump chip and the electro caps on the footswitch PCB and taking another look at solder joints. Also, check for shorts across the 100uf caps on the footswitch board.

Charge pump and electros are oriented as shown in the build doc photos.

Pin 5 is still the same after reflowing everything on the footswitch PCB.  Here's a pic of the other side of that PCB...



I did check the strip at the top and get about -9v on the third from the right and +9.4v or so on the fourth, about 0.128v on 7 and 8 and the rest are zero.

Does that help?

Also, R5 is the resistor in the far bottom left of the pic (horizontal). Wiring could connect there, but looks like it goes straight up from the switch to possibly the wrong resistor?

Yep bottom right in the long row.  It just looks odd because I have the wire run up and over to look a bit cleaner.  I checked across R5 and with the switch in each position I have about...

450 ohm
2.4k ohm
1k ohm

That's what I was shooting for with my values (1.8k and 560 in parallel if I recall) so that "mod" seems to check out.

[cajone5]

Shoot -- just checked continuity and I'm getting continuity across one of the 100uf electros... swapping now...

Swapped and voltage is now abou -8.9v on pin 5 so that problem is fixed.

-- Bright switch still doesn't work when flipped to the right although if I crank every knob I get a faint well-below-unity clean tone coming out... guessing I have something in there that's the wrong value but unclear where to start looking

-- Treble control still works backwards which makes no sense to me unless I have a ottally wrong value somewhere (again).

Overall, it still sounds flubby and somewhat gated and that probably indicates an error in the tone control as I am guessing I've screwed something up and choked the high end?

Thanks for the great help so far!

[cajone5]

Backwards treble control would have to be an issue with C20/C22/C24/C25 -- without removing them they appear right... it's odd.

The switch could be an issue with C20 or C21 I'd guess but they look good too... I'm lost.  I'm not sure I'll get back to this until next week.  Heading out for a wedding tomorrow morning.  Oh well, hopefully I can sort it out when I get back.

[somnif]

Your diodes look very different from the 695's I ordered, were their Fv's in spec?

[jubal81]

Yeah, I think you're probably on the right track. Sounds like it could be that you got some values mixed up in the tone stack area.

Also, when you get a chance, check the voltages on the middle leg of the BC549Cs. That'll tell us if the gain stages are operating OK.

[jubal81]

Your diodes look very different from the 695's I ordered, were their Fv's in spec?

The 1N695s I got from Smallbear are gray like that, too. Mine checked out.

[cajone5]

Yes forward voltage around 0.3v for the smallbear 1n695s

For the transistors -- voltages on middle leg...

Power: 9.5v

Q2 - 3.675
Q4 - 4.222
Q6 - 2.775
Q9 - 1.155
Q11 - 0.901

[midwayfair]

Check the voltages on the transistors (all legs) on either side of the treble control *while you're turning it.* Do any of them change?

[jubal81]

Yes forward voltage around 0.3v for the smallbear 1n695s

For the transistors -- voltages on middle leg...

Power: 9.5v

Q2 - 3.675
Q4 - 4.222
Q6 - 2.775
Q9 - 1.155
Q11 - 0.901

Voltage on Q2 is good, the others are jacked, especially 6&11. Check to make sure the 10R resistors are actually 10R or those other Electro caps could be junk, too.

[cajone5]

Checked 10R resistors...

R7, R10, R15, R22, R30, R33, R41, R49, R51 all measure 10.2 - 10.5R

For the transistors, I think Q9 is nearest the tone stack but here are all the voltages on all legs with treble at minimum, around middle and maxed... Spoiler alert, no change in any reading regardless of treble setting...

             Min | Mid | Max (Treble pot setting)
Q2 C - 9.40 | 9.40 | 9.40
Q2 B - 3.68 | 3.68 | 3.68
Q2 E - 3.06 | 3.06 | 3.06

Q4 C - 9.42 | 9.42 | 9.42
Q4 B - 4.19 | 4.19 | 4.19
Q4 E - 3.60 | 3.60 | 3.60

Q6 C - 9.42 | 9.42 | 9.42
Q6 B - 2.74 | 2.74 | 2.74
Q6 E - 2.16 | 2.16 | 2.16

Q9 C - 9.42 | 9.42 | 9.42
Q9 B - 1.16 | 1.16 | 1.16
Q9 E - 0.55 | 0.55 | 0.55

Q11 C - 9.42 | 9.42 | 9.42
Q11 B - 0.90 | 0.90 | 0.90
Q11 E - 0.37 | 0.37 | 0.37

[jubal81]

Always best ideas in the shower ...

Looked at voltages, came back and checked and see that you don't have any 3K3 resistors in your build. Look like they could be 10K.

[somnif]

Good eye. Well 10k or 120 ohm, depending on their orientation.

3.3k is... Orange Orange Red Brown Brown for 1%'ers I think? Or Orange Orange Red Brown in 4-band speak? (Still waiting on mine to get here in the mail, bloody tricky value to find, annoyingly)