PLEASE HELP...calling on anyone who's built the Aion Lab L5 preamp pedal

[jl2556]

Hey guys, 1st time posting here. (please be kind....lol). I took on the task of building the aion Lab L5 preamp pedal and am having issues from the start. My experience is novice with building pedals (built one from byoc a few yrs ago) but I'm good at following directions and was comfortable enough with a soldering iron to take on this project,though I had some issues with soldering the mini toggles as seen in the pics...lol). I figured if I took my time I could get through it......nope. I'm am having issues from the start. The only thing working is the bypass switch. I get no lights to any of the leds. When trying to engage the channels all I get is humming,though turning up the master makes the hum louder and messing with the multifilter knobs makes the phase/pitch/freq of the hum change. Out side of looking up a few of the symbols in the schematic,  I 'm a bit clueless on how how to read it or diagnose the issue. There is separate pwr section of the schematic in the documentation. 
Here's the link to the build with the pcb layout and schematics (the download link is at the top right):
https://aionelectronics.com/project/l5-preamp/

Things I've checked that are correct according to the schematic:
-orientation of all the electro caps, diodes and semiconductors and IC chips
-the tantalum cap at C40 is installed right...I caught the (+) symbol the 1st time
-continuity of all the wires to the pcb board from the input/output jacks, and all the wires from the 2 small pcbs at the bottom that have the foot switches mounted to.
-continuity of ground of the pedal box to the ground circuit
-continuity of the ground at the pwr jack and where it attaches to the pcb.

I'm wondering if my pwr supply is what the issue is. I bought a used presouns interface a few yrs ago that came with a sure mic pwr supply. It would light up but not function. Getting the right pwr supply fixed the issue. That's why I'm wondering if the pwr supply is my issue.....anyways, the directions say to use a AC pwr supply from Line 6 that was used in the DL-4, which was a PX-2 or PX-2g .
Here's the specs from the line 6 website.:
PX-2/PX-2g AC: Output: 9V AC, 2000mA. Plug Length: 10.5mm, Diameter: 5.5mm, Center Pin: 2.5mm.
On a pic from the sweetwater website for the older PX-2, on the adapter it says: input is is 120vac 60hz 40w 240 mA//output is 9vac 2000mA

To save $$ I bought a generic power supplythat says it works with the DL-4 (9V AC 2.1A), this is what I bought:
https://www.amazon.com/HQRP-Adapter-Stompbox-Modelers-98-030-0042-05/dp/B00HWTQH7W

I hope someone can help me as I got about $280+ in parts, including a nice box all done up from pedal parts plus as well.

Here's a few pics of my build:

[PRR]

Welcome.

> I 'm a bit clueless on how how to ...diagnose the issue.

https://www.diystompboxes.com/smfforum/index.php?topic=29816.0

That has you report "all" voltages. The L5 is insanely complex. Start with power supply voltages, TEST+ and TEST-. Move on to each chips' power pins, noting that each may be different pin numbers. Where you can decipher the "output" of a stage (such as pin 6 on '3080) report the DC voltage there. (But do NOT put a probe on pin 5 of '3080--- good way to blow it!)

Where did you get your '3080s? There are MANY fakes on the market.

[duck_arse]

also welcome.

at the very least, you need a ground wire on the jack on the right of your photos.

but, worse, this:


notice in the top right corner, the two voltage regulators are mounted with the metal tab [the "heatsink"] facing the free air above the board. your photos show them mounted .... different.

[bluebunny]

If I were to start a new secondary career in first-aid, then I'd probably not start with brain surgery!      But good on you for having a go, albeit at the very deep end.   

What's the deal with the wire link at the top of the board?  Also: judging by the pasty-looking solder joints on the switches, I'd say your iron isn't hot enough.  Which means you've had it sat on the joint for ages to get the solder to move at all.  Which means the pretty red resin stuff in the switches may have melted.  (We call this a "learning opportunity". )

Anyway, do what Paul says.  I'd personally remove the ICs before testing, although it could be a bit late to find they're in backwards (I don't think they are) or they've had the wrong voltages applied (possibly).  And check those regulators!

[jl2556]

Welcome.

> I 'm a bit clueless on how how to ...diagnose the issue.

https://www.diystompboxes.com/smfforum/index.php?topic=29816.0

That has you report "all" voltages. The L5 is insanely complex. Start with power supply voltages, TEST+ and TEST-. Move on to each chips' power pins, noting that each may be different pin numbers. Where you can decipher the "output" of a stage (such as pin 6 on '3080) report the DC voltage there. (But do NOT put a probe on pin 5 of '3080--- good way to blow it!)

Where did you get your '3080s? There are MANY fakes on the market.

Thanks for replying. Checking a powered circuit makes me nervous as that's where my being comfortable stops....though I know it needs to be done.
As far as the 3080s. They are lm3080n, the documentation said the lm would be o.k. I got them from surplus electronic sales:
http://www.surplus-electronics-sales.com/index.php?main_page=product_info&cPath=42&products_id=868

[jl2556]

also welcome.

at the very least, you need a ground wire on the jack on the right of your photos.

but, worse, this:


notice in the top right corner, the two voltage regulators are mounted with the metal tab [the "heatsink"] facing the free air above the board. your photos show them mounted .... different.

WOW!!! I installed them according to the pcb layout in the documentation, which shows the part #s on the top. I didn't know the difference. I never thought they would go in another way. I sometimes do some major body kit accessory installs on vettes and camaros etc at work and absolutely have to follow those directions to keep from messing up expensive rides so I'm used to doing only what the instructions say. Man I hope that's that simple as swapping the regulators and haven't tore up anything in the process.......

[jl2556]

If I were to start a new secondary career in first-aid, then I'd probably not start with brain surgery!   

LOL......I totally deserve that

What's the deal with the wire link at the top of the board?

Those 2 bare wires are for calibrating the distortion and compressor trim pots.

Also: judging by the pasty-looking solder joints on the switches, I'd say your iron isn't hot enough.  Which means you've had it sat on the joint for ages to get the solder to move at all.  Which means the pretty red resin stuff in the switches may have melted.  (We call this a "learning opportunity". )

All the switch holes were by far the hardest thing for me to get soldered. I have a weller wlc 100 40watt iron and it was set a little past the 3 position. I just didn't have the technique to fill those large gaps around the terminals nicely. I used the same small chisel tip I was using for everything else and only had the iron on there about 3 sec or so, added solder, and blew on the terminal for 5-6 seconds before I went in with more solder trying to keep from over heating the switches. IIRC, I checekd the continuity of the the switches afterwards to make sure I didn't tear one up, though I'll do it again to make sure.

Anyway, do what Paul says.  I'd personally remove the ICs before testing, although it could be a bit late to find they're in backwards (I don't think they are) or they've had the wrong voltages applied (possibly).  And check those regulators!

I'm near certain I got those installed right. I looked at pics from other builds and my dots on the top of the ICs are all up and to the left like theirs. I'll swap the regulators and cross my fingers. Being the regulators were installed backwards, is there a possibility I fried something else or would they just not work like what's going on now?

[basilisk]

WOW!!! I installed them according to the pcb layout in the documentation, which shows the part #s on the top. I didn't know the difference. I never thought they would go in another way.

Eh, we've all been there, overlooking something - some of us, myself included, more than once and definitely more than we would have liked! Once you flip the regulators and put them heat sink side up, measure the voltage between "+15/test" and "test/-15" pads near the regulators, you should get +15 and -15 volts, so you know you have correct voltage and you're on the right track. Good luck!

-B

[PRR]

> Checking a powered circuit makes me nervous

This rig is 50V 0.1 Amps. So not as bad as getting your wedding ring across a Camaro battery, or grabbing bare spark-wire on a hot Vette. It is laid out as +/-25V (raw) around ground. 24V is generally considered quite safe.

Yeah, you can do more damage blundering around inside with power on, but you may have blundered before power-on. We'll see.

I never heard of that surplus shop where you got '3080s. They may be reputable, but probably have no way to test, and the last decade the market has been flooded with unwanted/reject 8-pin chips re-painted as "3080". Small Bear Electronics seems to be the #1 reliable source. He has large customers relying on his '3080s being good. He works with Rochester El who is making new '3080s, but they aren't kind to small orders; the Bear is happy selling ones and twos. But let's get the power supply sorted first.

[bluebunny]

Man I hope that's that simple as swapping the regulators and haven't tore up anything in the process.......

TBF, the picture isn't perhaps 200% clear, but the clue is the square pad, which is usually pin 1 (the leftmost with the writing towards you).  The writing is intended to be just in terms of the layout: it's not supposed to mirror the writing on the regulator (which you shouldn't be able to see).  Another clue is "heatsink faces upward".  The heatsink is usually attached to the back of the package, i.e. the metal tab without the writing.  But it's easy to miss these details - been there, done that.      It hasn't killed you, so you must have learned something. 

Anyway, from what I can recall anecdotally, reversing the regulators may not have killed them.  There's only one way to find out...

BTW, definitely turn up your iron.  You should practise a little on some vero and aim to be in and out within two seconds.  If you can't get the solder flowing all over your joint in that time, it's not hot enough.  Same timing for big hairy things like switches, but because of the larger real-estate to warm up, raise the temp further.  This all comes with practice.  You'll get there.  Just try a nice simple one-transistor booster next time.   

[jl2556]

Anyway, from what I can recall anecdotally, reversing the regulators may not have killed them.  There's only one way to find out...

I got the regulators installed right. I made a little progress.

Things that are working now:
-all the pots
-hi/low input switch (not sure about the bright switches, volume too low to tell)
-the channel switch

Things not working:
-VERY low output
-engaging the compressor switch kills all the output on either channel

When engaging the channels, it has a VERY weak output and still no leds are lighting up. I accidentally left my multimeter on the last time I worked on it so I need to get a battery for it to test the -15/+15 voltage at the test point.
At this point I assume I tore up both or 1 of the regulators, though I know I still need to test them, I will tonight...

Hypothetically, if the regulators are good, what' should I check next? would have installing them backwards, killed a ic chip? If the regulators are bad, I assume they would they not be feeding the correct amount of current to make the pedal work BUT.... are feeding enough current to barely make it work, such as the extremely low output?

[jl2556]

I just wanna say thanks to all you guys for trying to help me, I know I took on a big project but really want to lean how to diagnose issues like this. I know I'm a noob and I might ask some questions that seem very elementary to you guys but just bear with me... all your help will not be for nothing

[bluebunny]

Good to see progress!      Next step is the sticky "Debugging" thread that Paul linked to in his first reply.

[jl2556]

O.K. guys, finally got some time to work on this again.
Things I've checked:
-put my meter on the DC 20V setting, put power to the pedal and got the -15.13/+14.97 at the test points
-using the same DC 20V setting, I checked all the IC chip voltage

I only got the Ic chips tested so far due to a bad choice on my part. The bad choice was trying to remove the
transistors to put in the transistor testing section of my multi meter, why didn't I test them 1st that way, I didn't know that's what that was as I've never had
to test a transistor. I got 2 out (QX1 & QX2 on the schematic). The 1st one I pulled up too hard and pulled one of the legs out of the transistor case.
Anyways, learning as I go......lol. Gonna re order all the transistors just in case and use sockets next time...

Again here's the doc link for the pedal so you can see where each Ic chip is on the layout.
https://aionelectronics.com/project/l5-preamp/

*** The LM741P that was required in IC positions 2 & 13, when looking at the chips with a magnifying glass, had LM741CN on them, I hope that's just a super seeded part # for the LM741P....


IC 1 (LF356N)        IC 2 (LM741P)             IC 4 (RC4558P)           IC 5 (RC4558P)           IC 6 (RC4558P)            IC 7 (RC4558P)      IC 8 (RC4558P)
p1: 0                    p1: -15.12                  p1: -.01                   p1: .02                     p1: -.03                      p1: -.03               p1: -.02
p2: 0                    p2: 0                         p2: 0                       p2: .02                     p2: 0                          p2: 0                   p2: 0
p3: 0                    p3: 0                         p3: 0                       p3: .02                     p3: 0                          p3: 0                   p3: 0
p4: -15.13             p4: -15.13                  p4: -15.13               p4: -15.13                 p4: -15.13                   p4: -15.13            p4:-15.13 
p5: 0                    p5: -15.13                  p5: 0                       p5: .01                     p5: 0                          p5: 0                   p5: 0
p6: 0                    p6: 0                         p6: 0                       p6: 0                        p6: 0                          p6: 0                   p6: 0
p7: 14.97              p7: 14.97                   p7: -.04                   p7:0                         p7:-.04                       p7: -.04               p7: -.04
p8: 0                    p8: 0                         p8: 14.97                 p8: 14.97                  p8: 14.98                    p8: 14.97             p8: 14.97




IC 9 (RC4558P)      IC 10 (LM3080)           IC11 (LM3080)           IC 12 (RC4558P)
p1: 0                   p1: 0                         p1: 0                       p1: -.01
p2: 0                   p2: 0                         p2: 0                       p2: 0
p3: 0                   p3: 0                         p3: 0                       p3: 0
p4: -15.13            p4: -15.13                 p4: -15.13                 p4: -15.13
p5: 0                   p5: -14.98                 p5: -14.59                 p5: 0
p6: 0                   p6: .72                      p6: .13                     p6: 0
p7: 0                   p7: 14.97                   p7: 14.97                 p7: 0         
p8: 14.97             p8: 0                         p8: 0                       p8: 14.97 

[jl2556]

Alright guys, I got the transistors in I tore up trying to get out. Here is the test results of the transistors & both of the zener diodes. I tested with the voltage setting at 20 Dc on my multimeter using the (test) hole on the board as my ground. Again, my readings from the pwr section test points +15/-15 are good. I'm also getting 14.98 V at the LED wire at the footswitch but the lights are not coming on??? Also, in the pwr section of the schematic to the rt of the test points, there's some sort of bracket that shows +V to all the 8s on the top row and -V to all the 4s on the bottom. What is that referring to?
(The links for the schematics are in my 1st post.)

Transistors:

Q1 (2N5457)
D-  14.98
S-  .88
G-  .51
-----------
Q2 (2N3906)
E-  0
B-  0
C-  -14.60
----------
Q3 (MPSA13)
E-  -15.13
B-  0
C-  0
----------
QX1 (2N5088)
E-  0
B-  0
C-  14.98
----------
QX2 (2N5088)
E-  14.98
B-  0
C-  0

Zener Diodes:

D4 (1N914)
A-  0
K-  14.14

D5 (1N914)
A-  0
K-  14.23


Here's the IC results again as well:
IC 1 (LF356N)        IC 2 (LM741P)             IC 4 (RC4558P)           IC 5 (RC4558P)           
p1: 0                    p1: -15.12                  p1: -.01                   p1: .02                   
p2: 0                    p2: 0                         p2: 0                       p2: .02                     
p3: 0                    p3: 0                         p3: 0                       p3: .02                   
p4: -15.13             p4: -15.13                  p4: -15.13               p4: -15.13                 
p5: 0                    p5: -15.13                  p5: 0                       p5: .01                     
p6: 0                    p6: 0                         p6: 0                       p6: 0                       
p7: 14.97              p7: 14.97                   p7: -.04                   p7:0                       
p8: 0                    p8: 0                         p8: 14.97                 p8: 14.97     
             

IC 6 (RC4558P)            IC 7 (RC4558P)      IC 8 (RC4558P)
p1: -.03                      p1: -.03              p1: -.02
p2: 0                          p2: 0                   p2: 0
p3: 0                          p3: 0                   p3: 0
p4: -15.13                   p4: -15.13            p4:-15.13
p5: 0                          p5: 0                   p5: 0
p6: 0                          p6: 0                   p6: 0
p7:-.04                       p7: -.04               p7: -.04
p8: 14.98                    p8: 14.97             p8: 14.97


IC 9 (RC4558P)      IC 10 (LM3080)           IC11 (LM3080)           IC 12 (RC4558P)
p1: 0                   p1: 0                         p1: 0                       p1: -.01
p2: 0                   p2: 0                         p2: 0                       p2: 0
p3: 0                   p3: 0                         p3: 0                       p3: 0
p4: -15.13            p4: -15.13                 p4: -15.13                 p4: -15.13
p5: 0                   p5: -14.98                 p5: -14.59                 p5: 0
p6: 0                   p6: .72                      p6: .13                     p6: 0
p7: 0                   p7: 14.97                   p7: 14.97                 p7: 0         
p8: 14.97             p8: 0                         p8: 0                       p8: 14.97