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Projects => VFE Projects => Topic started by: Masochist on September 07, 2019, 12:17:26 AM

Title: Klein Bottle problem :(
Post by: Masochist on September 07, 2019, 12:17:26 AM
So I've just finished putting my Klein Bottle together but unfortunately I'm having some issues.

There's output when I plug the guitar into the input and the Master Volume pot is responsive but when I try to engage the footswitches the LEDs don't light up. I haven't got any pedals plugged into the in/outs but I don't think the input jacks are switching so I don't think that would be the issue. I put the LEDs Cathode into the square pad and the Anode into the circular pad, could I have installed them the wrong way?

I'm trying to decipher the schematic to attempt to trace the problem. Trying to work out where to start.. the power input is the top left of the schematic, right? I checked with a DMM to see if I'm getting 9V at the input and that seems fine.

If anyone has any tips on how I should go about tracing the problem I'd really appreciate it. Hopefully this could be a great learning experience in troubleshooting circuits! Anyway, looking forward to hearing back, thanks in advance :)
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 07, 2019, 12:40:56 AM
Might have prematurely posted.. I grabbed another similar LED and tried touching the Cathode to the circular pad and Anode to the square pad. When I pressed the footswitch it lit up!! So now I'm in the process of taking it apart so I can switch the LEDs around. Hopefully this is my only problem with this build!!
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 07, 2019, 02:51:57 AM
One more question.. I've removed the LEDs but I'm having trouble removing all the solder from the pads to I can install the LEDs back the 'correct' way. I've got a solder sucker thing and solder wick, but can't seem to remove some of the solder.

Does anyone have any tips to try to remove the stubborn solder? Should I try to use a higher temp or something?
Title: Re: Klein Bottle problem :(
Post by: EBK on September 07, 2019, 04:37:21 AM
I remove solder by holding the board up, dipping my soldering iron tip into some solder paste that I stole from Brian, heating the solder from underneath, and letting gravity do the work.
Title: Re: Klein Bottle problem :(
Post by: alanp on September 07, 2019, 04:58:39 AM
I use a stainless steel dentist's pick from Smallbear, for things like that.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 07, 2019, 05:38:45 AM
I use a stainless steel dentist's pick from Smallbear, for things like that.

Interesting! How does that work? Do you heat the pad up as much as possible then use the pick to push the solder through?
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 07, 2019, 08:50:30 AM
Ended up hitting em with the hot air gun and that seemed to do the trick! Was thinking I might have to macgyver up something like wrap a paperclip around my soldering iron tip!

Would still like to hear about this dental pick thing tho!! :)
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 07, 2019, 09:12:35 AM
I always had problems with cheap solder suckers. The engineer SS-02 solder sucker with the silicon tip has been a great improvement. A little spendy, but great results and no where near the expense of a real-deal desoldering station.
Title: Re: Klein Bottle problem :(
Post by: somnif on September 07, 2019, 12:01:08 PM
I use copper braid solder wick, with a little added flux. Braid on pad, iron on braid, rub rub rub.

Through-hole pads can take a moment, but the movement of the braid really helps it "suck" solder. Keep the iron stationary holding the braid in place, and wiggle the braid and forth so the strands move a bit (extra capillary action!)
Title: Re: Klein Bottle problem :(
Post by: Aentons on September 07, 2019, 01:44:09 PM
I use copper braid solder wick, with a little added flux. Braid on pad, iron on braid, rub rub rub.

Through-hole pads can take a moment, but the movement of the braid really helps it "suck" solder. Keep the iron stationary holding the braid in place, and wiggle the braid and forth so the strands move a bit (extra capillary action!)

I've never gotten the hang of the wick, the iron tip always goes right through the braid. I have a 40 year old pump action solder sucker with a tip  that's all eaten up that works like a charm (almost) every time.
Title: Re: Klein Bottle problem :(
Post by: diablochris6 on September 07, 2019, 09:48:28 PM
In a pinch, I have used a wooden toothpick to push through some stubborn solder. I hold my board with the thumb and middle fingers, and my index finger puts slight pressure on a toothpick against the blocked pad. On the other side of the board I apply heat with the iron. The toothpick slides right through until the taper of the point is too wide.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 08, 2019, 06:40:58 AM
That's a cool technique! Will keep that one in mind.

One more question, does anyone know where to source the knobs that are used on the retail KB?
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 08, 2019, 08:44:36 AM
One more question, does anyone know where to source the knobs that are used on the retail KB?

These are what came with the kit:
https://www.mammothelectronics.com/products/ka-15x13-series-aluminum-knurled-knob-15-x-13mm?_pos=1&_sid=2440c889f&_ss=r (https://www.mammothelectronics.com/products/ka-15x13-series-aluminum-knurled-knob-15-x-13mm?_pos=1&_sid=2440c889f&_ss=r)
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 08, 2019, 09:19:16 AM
Thank you kind sir!
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 08, 2019, 02:24:01 PM
Sure thing. By the way, did you see that Peter released modifications to help deal with signal bleed?
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 08, 2019, 04:10:27 PM
Yep how could I not notice that hulking cap haha!! I thought about doing the mods initially as when I saw Peters video I didn't even have the 9mm pots and switches soldered in yet, would have been the perfect time to do it really. But I figured that I didn't even know if the pedal worked yet! So yeah, I'll do some tests and make sure it all works and then I'll think about doing the mod.

Is the signal bleed etc really that bad? Cheers man.
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 08, 2019, 04:52:47 PM
I havenít placed a mouser order since the mod was announced, so I havenít done it yet. (Maybe EBK has.) The bleed is definitely there. Itís faint, but if youíre running some hot signals, itís high enough that it could mess with things. Itís not a dealbreaker on the unitóitís terrificóbut it is noticeable.
Title: Re: Klein Bottle problem :(
Post by: EBK on September 08, 2019, 05:09:41 PM
I view the mods as a fix of a defect rather than an improvement, if that makes sense.  It would bother me not to do the mods, but I haven't placed a parts order yet.
Title: Re: Klein Bottle problem :(
Post by: Aentons on September 08, 2019, 05:14:02 PM
I view the mods as a fix of a defect rather than an improvement, if that makes sense.  It would bother me not to do the mods, but I haven't placed a parts order yet.

Every Ibanez tube screamer that I've ever played has a bypass bleed issue. It's faint, but it's there. Crank the gain all the way up and take a listen with it off.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 08, 2019, 06:31:06 PM
Ok you've sold me! I will definitely do the mod :) I watched the video the day it came out and it's great that it can all be performed without having to remove the board. Opening that thing up again seems like a daunting task at this stage, so I think I'll give it a little while.

Good luck with your mods though, would love to hear how u guys get on!
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 08, 2019, 09:52:21 PM
I'm shopping for parts for this mod.. seeing as I really only need the 10000uf cap and due to Mouser's expensive shipping to Australia I'm trying to find an alternative on RS. I found this one..

https://au.rs-online.com/mobile/p/family-id/7442029/

It looks pretty similar in size, a little shorter in length and it's life is 2000 hours compared to the Mouser one having 10000 hours. What do you guys think?
Title: Re: Klein Bottle problem :(
Post by: EBK on September 09, 2019, 04:57:53 AM
Could also make an op amp buffer daughter board to create a buffered Vref.  I'm debating whether to do this instead of buying a BFC. 
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 09, 2019, 09:08:33 AM
Could also make an op amp buffer daughter board to create a buffered Vref.  I'm debating whether to do this instead of buying a BFC.

This sounds interesting although I have no idea what you're talking about! Could you explain what you mean? Are you thinking about making some kind of veroboard thing?

Do you think that cap I linked to matches the recommended one enough? I ended up just ordering it anyway. I think it cost me $6 inc postage so no big loss if I've made the wrong decision.
Title: Re: Klein Bottle problem :(
Post by: EBK on September 09, 2019, 09:41:37 AM
I need to look more closely at the mods and the schematic, but my understanding is that the bleedthrough is happening, at least partly, because the Vref is varying as the op amps draw current out of that node in proportion to the signals they are working on.  Peter's fix, that extraordinarily large cap, is a giant reservoir where that current can come from when the demand is high (and then the cap can be recharged as the current need swings the other way).  In this way, it basically filters the voltage fluctuation.  But, a more elegant way to do this (in my humble opinion) is to add a simple buffer to the Vref node.  I would consider doing this with a very tiny veroboard with a TL072 on it.  The op amp would take care of supplying the fluctuating current at a constant voltage.
 Smaller and possibly even cheaper than the Capacitor-of-Unusual-Size solution.  I have plenty of veroboard scraps around, and I always have a spare op amp, so I may give it test sometime and report back. 

But, again, I need to look more closely at it all first.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 09, 2019, 03:56:20 PM
Awesome!! Sounds plausible but then again I know very little. I too have many spare TL072's and veroboard scraps. Please do keep me up to date. Would love not to have to replace this hulking cap after 2000/10k hours!
Title: Re: Klein Bottle problem :(
Post by: EBK on September 10, 2019, 08:13:30 AM
Here is what I've sketched up.  This would probably make the other resistor value swaps unnecessary.  Haven't looked into that extra resistor Peter attaches to the transistor yet though.
(https://i.imgur.com/Bd5BXIt.jpg)
I've somewhat arbitrarily chosen 10k for my resistors in my schematic. Feel free to chose another value if you are low on those.

I haven't tested this, but I do plan to eventually.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 10, 2019, 09:19:52 AM
This is fantastic! Thanks so much for keeping me up to date! Can you tell me what the circle around one of the connections means at the bottom right of the vero drawing?
Title: Re: Klein Bottle problem :(
Post by: EBK on September 10, 2019, 09:22:19 AM
This is fantastic! Thanks so much for keeping me up to date! Can you tell me what the circle around one of the connections means at the bottom right of the vero drawing?
That's how I draw a resistor standing up vertically on the board.  Sorry for the confusion.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 10, 2019, 11:27:26 AM
Sorry I'm still a little confused.. I've attached a screenshot where I've circled the part in question. To the right of it I see the symbol for a resistor and to the right of the resistor I see the symbol for a bipolar cap but I thought a straight line meant simply a point to point connection with hookup wire? Sorry man I'm kinda new to all this, just trying to understand and hopefully learn something! :)
Title: Re: Klein Bottle problem :(
Post by: EBK on September 10, 2019, 11:36:05 AM
I may be the only person who draws it like this, so don't feel bad about being confused.  It is meant to graphically represent how this looks, with the circle being the resistor body viewed from above:
(https://i.imgur.com/hMAmesPl.jpg)

I've actually spent the past hour (more or less) building this board.  In my build, I opted to lay that resistor down flat, and I bent the leads a little funny.  The top lead of my ceramic cap is also moved up, but this is electrically the same (the rows are connected by the jumper to the left).
(https://i.imgur.com/5OPcGsml.jpg)
And, covered in some heat shrink:
(https://i.imgur.com/p8fuOYUl.jpg)
Title: Re: Klein Bottle problem :(
Post by: Govmnt_Lacky on September 10, 2019, 01:03:48 PM
...dipping my soldering iron tip into some solder paste that I stole from Brian

I don't know if anyone has mentioned this but, THIS is NOT a good idea. Solder paste is highly corrosive and will dramatically shorten your irons tip life.

Just my 2  ;)
Title: Re: Klein Bottle problem :(
Post by: EBK on September 10, 2019, 01:14:17 PM
...dipping my soldering iron tip into some solder paste that I stole from Brian

I don't know if anyone has mentioned this but, THIS is NOT a good idea. Solder paste is highly corrosive and will dramatically shorten your irons tip life.

Just my 2  ;)
My current tip has been going strong for over 4 years (since my soldering station was brand new).  The previous soldering iron tip I used also did not wear out from corrosion (I probably used it for 10 years or more, and it also came with the iron when it was new).  In fact, I have only once in my life replaced a tip due to corrosion (the crappy Radio Shack iron I learned to solder with).
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 10, 2019, 01:24:02 PM
Has anyone tried contacting Peter about the added buffer? He might have some good insight/be interested with changesóespecially if heís considering a rev 2 of the board.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 10, 2019, 04:28:32 PM
Very nice! Ok I think I get the layout now. Have you had a chance to test it with the KB? Really itching to know if this is viable! Great work regardless man.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 10, 2019, 04:31:56 PM
Has anyone tried contacting Peter about the added buffer? He might have some good insight/be interested with changesóespecially if heís considering a rev 2 of the board.

I was thinking about emailing him but I might leave that to the actual creator of this potentially excellent alternative.. EBK have you tried getting in touch with Peter?
Title: Re: Klein Bottle problem :(
Post by: EBK on September 10, 2019, 04:48:58 PM
I haven't even tested this yet. 

I don't mind anyone sharing the idea with Peter, and I don't mind him using it if he wants, but I don't need any credit for it.  It is a trick used in many many other circuits and not an idea I invented.  Peter may have already thought of it but opted for a simpler design for cost reasons.  My fix
requires many more solder joints and creating a new board.  His fix is suitable for his board layout with very minimal modification.

(In other words, I am humble and shy.  ;))
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 10, 2019, 04:58:59 PM
I haven't even tested this yet. 

I don't mind anyone sharing the idea with Peter, and I don't mind him using it if he wants, but I don't need any credit for it.  It is a trick used in many many other circuits and not an idea I invented.  Peter may have already thought of it but opted for a simpler design for cost reasons.  My fix
requires many more solder joints and creating a new board.  His fix is suitable for his board layout with very minimal modification.

(In other words, I am humble and shy.  ;))

Haha, Iíll leave it to you to email him. I encourage you to do so, though. I bet he didnít offer this as a solution because it requires a daughter board, but a board revision could totally implement it. Itís a four layer pcb that isnít exactly small...Iím sure thereíd be space.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 10, 2019, 09:45:05 PM
Nearly finished constructing the board. Is that a 100nf MLCC you list there? I don't think I have one of those bad boys.. I've got some 100nf film caps though, will they do the trick or should I go and source a 100nf MLCC?

Also, have you crossed out R68 and R69 on the diagram for connecting the board because you're saying to remove these resistors first? Thanks man :)
Title: Re: Klein Bottle problem :(
Post by: EBK on September 11, 2019, 05:56:17 AM
Nearly finished constructing the board. Is that a 100nf MLCC you list there? I don't think I have one of those bad boys.. I've got some 100nf film caps though, will they do the trick or should I go and source a 100nf MLCC?

Also, have you crossed out R68 and R69 on the diagram for connecting the board because you're saying to remove these resistors first? Thanks man :)
For something trivial like this, a 100nF film cap is probably ok.  It is just a decoupling cap.  Ceramic caps work better at shunting high frequency noise than most other types of caps.  Try to keep the wires going to the buffer board short though.

If you are going to use the buffer board, then, yes, omit R68 and R69.  The two resistors on the buffer board perform the voltage divider function instead.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 11, 2019, 06:34:27 AM
Great, thanks for your help with this!  I'll have it installed tomorrow morning at some stage once I receive my MLCC's and pick up some heat shrink tubing.

It doesn't matter what side I solder the leads to on the resistors, right? I'm just going to utilise the same technique Peter used and snip the existing resistors and solder the leads from the new daughter board to the original resistor leg nubs. Should be fine just to leave the board unsecured do you think? I'll just keep the leads as short as possible.
Title: Re: Klein Bottle problem :(
Post by: EBK on September 11, 2019, 07:03:43 AM
It doesn't matter what side I solder the leads to on the resistors, right?
I'm confused by this question.  Are you asking about which pads on the Klein Bottle PCB you should attach the buffer board to?

The buffer board wires must go to specific pads on the Klein Bottle board. 

The left side pad for R68 on the PCB is the V+ bus.  This must be connected to the V+ wire of the buffer board.

The right side pad for R68 on the PCB is the Klein Bottle's Vref bus.  This is connected by a trace on the PCB to the left side pad of R69.  The Vref wire of the buffer board must connect to one of these pads.

The right side pad of R69 is connected to the ground pour of the PCB.  The ground wire of the buffer board must connect here (or at least to another spot on the board that is also ground).

I will try to solder mine up tonight and show you what I mean.

If you insulate your board with sone heat shrink tubing like I did, then you can probably let the board float unsecured inside the enclosure.  You should probably secure it somewhere with some double stick foam tape or hot glue to help ensure that the wires wont break from mechanical fatigue eventually.
Title: Re: Klein Bottle problem :(
Post by: EBK on September 11, 2019, 03:53:09 PM
Actually, I want to test a few things before I solder in my mod board.

1.  I want to measure Vref in the stock version.

2.  I want to recreate the bleedthrough so I can tell if I've improved it after my mod.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 11, 2019, 04:57:54 PM
Sorry for the confusion, I obviously still have a lot to learn!! My thinking was that because it doesn't matter what way around you put a resistor, it might not matter which way around I install the wires for the buffer board. Thanks for straightening that out!

Ok, I'll wait until I hear the results from your tests before I install the board. Thanks again!
Title: Re: Klein Bottle problem :(
Post by: EBK on September 11, 2019, 07:59:29 PM
Test 1.  The voltages I got (with all 3 loops in bypass) were:
9.43V at DC jack
8.82V on V+ bus
4.27V on Vref bus

I was curious whether the DC value of Vref was being pulled significantly lower than half V+.  Peter wrote +12V and +5V on his PCB trace diagram, suggesting he expected Vref to be slightly less than half V+.  This test was also a sanity check to make sure my buffer can handle the load (it can).

A quick calculation shows that the DC load on Vref (the effective resistance to ground in parallel with R69) is about 15.2k, resulting in about 0.28mA DC flowing out of the Vref node from the voltage divider.

With all 3 loops on, the DC current out of the Vref node was about 0.16mA.  V+ was 8.78V, and Vref was 4.31V.  27k load on Vref.


I don't quickly see any place in the circuit where this minor discrepancy seems to matter though, so I'm going to stick with my resistor choices on my buffer board, so my Vref post-mod should be higher.


Masochist, you don't mind me hijacking your thread with my mod stuff, do you?   :-[
I don't want to seem rude, and I can start a new thread if you want.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 11, 2019, 09:58:41 PM
I donít mind at all man! Iím highly appreciative of your help and itís been awesome seeing this mod develop! Maybe it deserves its own thread though, as some KB owners might skim over this thread after the first page. What do you think?
Title: Re: Klein Bottle problem :(
Post by: EBK on September 13, 2019, 07:36:13 PM
I can't seem to reproduce the bleedthrough problem.  I'm not sure what the magical combination of settings is.  Any ideas?
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 13, 2019, 08:16:33 PM
I can't seem to reproduce the bleedthrough problem.  I'm not sure what the magical combination of settings is.  Any ideas?

Are you in sends or all mode? Whatís the dry signal level set to?

I think the bleed is most prominent in ALL mode and also with the dry signal turned all the way down.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 15, 2019, 04:31:33 PM
I can't seem to reproduce the bleedthrough problem.  I'm not sure what the magical combination of settings is.  Any ideas?

Did you have any luck mate?
Title: Re: Klein Bottle problem :(
Post by: EBK on September 15, 2019, 05:06:59 PM
Haven't been able to try again yet.  Been juggling a few family and work things.  Sorry to keep you hanging. 
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 15, 2019, 05:12:36 PM
Haven't been able to try again yet.  Been juggling a few family and work things.  Sorry to keep you hanging.

No that's fine man, you have a life! Looking forward to hearing from you though :)
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 18, 2019, 04:24:46 PM
Hey did anyone end up emailing Peter about this? If not, let me know and Iím happy to attempt to see what he thinks?
Title: Re: Klein Bottle problem :(
Post by: EBK on September 18, 2019, 05:40:11 PM
Hey did anyone end up emailing Peter about this? If not, let me know and Iím happy to attempt to see what he thinks?
Go for it.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 20, 2019, 05:29:47 AM
Ok, email sent. Will let you know what transpires. Any chance you might have some time this weekend to attempt the testing phase again? Hope all's well with you.
Title: Re: Klein Bottle problem :(
Post by: EBK on September 20, 2019, 05:34:23 AM
I might try testing today.  Will let you know.

I'm trying to find the original description of the bleedthrough problem.  I can't remember if it was in one of the videos or on the website, or in one of the docs.  I want to understand what I'm trying to hear.
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 20, 2019, 01:15:08 PM
I'm trying to find the original description of the bleedthrough problem.  I can't remember if it was in one of the videos or on the website, or in one of the docs.  I want to understand what I'm trying to hear.

I think he mentions it in the build video as well as the kickstarter video. This is taken from the KB page on the VFE site:

Quote
"Due to design constraints when building a low noise circuit that ran on an industry standard 9-18V power supply, the signal to each effect loop has some bleed in ALL mode. This is one aspect of the Klein Bottle that I continue to research, and if I find a simple solution, I will share it openly."

The DRY knob is never really out of the circuit. That particular bleed issue isn't what's addressed with the big honkin' capacitor (BHC) fix, though. Here's the information about that:

Quote
Due to design constraints when building a complex & compact circuit, the dry knob is technically still active when all 3 loops are in bypass. However, it has been shunted to ground with an optocoupler. Because an optocoupler can't reach zero ohms of resistance, a tiny amount of bleed comes from the dry path. You can hear it in bypass if you crank up the dry signal, but even then it just makes the bypass signal a bit louder.

EDIT: I finally got my BHC. I'm holding off until hearing more about this daughterboard strategy. It reminds me of an M80.
Title: Re: Klein Bottle problem :(
Post by: EBK on September 20, 2019, 02:21:03 PM
So, when in ALL mode, with a loudish effect hooked up to one channel loop, I should hear it a tiny bit when bypassed, right? It's not dependent on any of the feedback stuff then.  I will give it a go.
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 20, 2019, 02:28:33 PM
So, when in ALL mode, with a loudish effect hooked up to one channel loop, I should hear it a tiny bit when bypassed, right? It's not dependent on any of the feedback stuff then.  I will give it a go.

I don't think that the feedback controls are crucial here. The PRE and MIX knobs are the main ones (although the makeup gain trim would also have a role). The feedback controls will have an influence as well, though; since there's signal bleed to each effect loop, there will be bleed to other channels if you're routing from it. The most prominent occurrence (I think) would be with the effects loops themselves.
Title: Re: Klein Bottle problem :(
Post by: EBK on September 20, 2019, 02:37:55 PM
So, in ALL mode, I sent loop 1 through my theremin fuzz.  I had the mix knob maxed and the pre knob at noon.  Nothing connected to loops 2 and 3.

When I clicked off loop 1, I heard the normal trail, then silence. 

With loop 1 on, I dialed the Mix knob to zero.  Silence. 

Maybe I need to try plugging my guitar into the return jack of loop 1 instead of using a pedal....  The theremin fuzz is a gated effect and although it sometimes will oscillate slowly when in idle, maybe it was just dead silent this time.

Some of my pots seem loose, electrically.  I get some oscillation in parts of their sweep (dry knob and Ch 1 Mix are two I've notice this with).  Maybe I need to reflow those joints.
Title: Re: Klein Bottle problem :(
Post by: EBK on September 20, 2019, 02:50:53 PM
I think I've got all sorts of wrong things happening.  If I crank the 1-to-3 knob to max, loop 1 is muted. Multiple pots doing weird things.  I'm stopping my testing until I get this back to working order.  Once I fix it up, I will try it again.  I haven't changed anything since my initial testing (when I verified that every control worked), and I haven't dropped the pedal or anything like that.  Must be cold solder joints (from not heating the heavy copper board enough).  I hope it is just that, anyway.
Title: Re: Klein Bottle problem :(
Post by: benny_profane on September 20, 2019, 05:22:41 PM
I think I've got all sorts of wrong things happening.  If I crank the 1-to-3 knob to max, loop 1 is muted. Multiple pots doing weird things.  I'm stopping my testing until I get this back to working order.  Once I fix it up, I will try it again.  I haven't changed anything since my initial testing (when I verified that every control worked), and I haven't dropped the pedal or anything like that.  Must be cold solder joints (from not heating the heavy copper board enough).  I hope it is just that, anyway.

Huh, I wonder whatís going on. Is this happening with different pedals in the loops? And this is just now happening? Nothing in the time since initial testing till now?
Title: Re: Klein Bottle problem :(
Post by: EBK on September 21, 2019, 06:18:42 AM
Just happening now.  Doesn't matter what pedals I have in the loop.  I haven't touched anything since I initially completed the build. I've let the pedal sit unused on a shelf between the time of initial successful testing and now. 
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 21, 2019, 10:17:17 AM
Ok Iíve just received a reply from Peter..

ďMy original design did use a buffer for the bias voltage, but it had some major issues. It's been so long since I was at that part of the design phase, so I can't remember exactly what the problems were. I just remember that when I abandoned the buffered bias and went to a simple voltage divider using 1k resistors, it worked great.Ē
Title: Re: Klein Bottle problem :(
Post by: EBK on September 21, 2019, 03:24:33 PM
I'm still going to move forward with the buffer board.  As an engineer, it makes sense to me, and I cannot see a scenario where it would cause a problem.  Of course, I need to fix other things before I move forward.
Title: Re: Klein Bottle problem :(
Post by: Masochist on September 21, 2019, 04:12:10 PM
I like your attitude!! I too will sit it out and await your results.
Title: Re: Klein Bottle problem :(
Post by: Masochist on October 02, 2019, 10:13:38 AM
Howís the KB repair going man? Found the source of the problem yet? Hopefully itís something obvious/easy to identify!
Title: Re: Klein Bottle problem :(
Post by: EBK on October 02, 2019, 10:51:42 AM
Haven't cracked it open yet.  Maybe tonight I will reflow all of the pots and switches.  Hoping that's all I need to do.
Title: Re: Klein Bottle problem :(
Post by: benny_profane on October 02, 2019, 11:04:59 AM
Haven't cracked it open yet.  Maybe tonight I will reflow all of the pots and switches.  Hoping that's all I need to do.

For your sake, I'm hoping that's the case as well.
Title: Re: Klein Bottle problem :(
Post by: Masochist on October 02, 2019, 04:38:02 PM
Keeping all extremities crossed for you!! Best of luck.
Title: Re: Klein Bottle problem :(
Post by: Masochist on October 24, 2019, 06:24:52 AM
Any luck getting your KB functional again dude?
Title: Re: Klein Bottle problem :(
Post by: EBK on October 24, 2019, 06:30:38 AM
Haven't worked on it.  Focusing on a couple other projects at the moment.