Langtronics - Bone Collector

moidphotos · Post by **moidphotos** » 07 Jun 2017, 23:40

Hello everyone

I'm a long time lurker that has learned many things about pedal building from this forum and now it's (hopefully) payback time. I got hold of a Langtronics Bone Collector a few years ago and wanted to work out how to mod it to get more control over the laser sounds it made and possibly install a mix between the dry and wet signal.. and looked inside it to discover the PCB and interior were covered in hot glue (glue gun glue? a white plastic) and gave up. Last weekend I opened it again and started to prise the glue off and have discovered that the glue becomes brittle with time and I was able to get most of it off the board without (I hope) damaging it. I've taken photos and made some drawings from the PCB (below) but here is where I need your help - I'm colour blind and cannot read the colours on the resistors (yes, it really sucks being interested in electronics yet being unable to tell one resistor from another, in case you wonder). Could someone here please help me with that? I can supply more photos of any part. I'd like to draw this up as a schematic so I can breadboard it and see if the circuit can be modified (Maybe the op amp can be used to generate a loud clean audio path as well as a wet one? I also want to get the trimpot to the outside of the box for more control. This is the first time I've tried to trace a circuit, so don't laugh at any beginner mistakes (but please point them out so I can learn)

Here is my drawing of the back of the PCB (trace side) with the components drawn on top (they are on the other side of the PCB)

This is my drawing of the copper trace with holes in white

Drawing of just the components (viewed from behind)

photo of the trace side of the PCB

photo of the front of the PCB

Flipped photo of the front of the PCB so it lines up with the drawings I've made (in terms of orientation)

Some of the components are confusing - the Vactrol is homemade and is a tube full of glue so I cannot tell what LED and LDR are inside it. I can't get the glue out of that part. Any suggestions you have for that part would be great. The Trimpot says 122 on the side of it, but I cannot find any trimpot with that size? Does it make sense to anyone here? There are numerous jumper cables on the top of the PCB - they are coloured green on the drawings. The back of the PCB was 'insulated?' with a sheet of white paper held on with glue gun glue (which explains why the pedal randomly shorts out when bashed with a foot...) and the entire PCB was glued into the enclosure... what a mess.

Thanks for any help, and do say if you need more pictures.

Edit: Sorry I don't know how to scale the pictures to fit - if you right click and choose View Image you can see the whole picture

dv8r601 · Post by **dv8r601** » 11 Jun 2017, 16:52

Thanks for the pics. I will check this out tomorrow. This looks like something I've seen before. Maybe on Beavis or somewhere like that. 386,555, and 072. Hmmmmmm

moidphotos · Post by **moidphotos** » 11 Jun 2017, 22:25

Great! If you find a schematic for this so I don't have to draw one I'll be really happy. I thought it might be based on something by Tim Escobedo, but I can't find anything in his schematics like this. I have been trying to draw a schematic from my diagram but that's pretty hard to do (for me at least) and I've discovered I made some mistakes in the images above that I need to fix. I've also had a go at using Photoshop to tell me the resistor colours, so maybe that will work... I'm still stumped as to the size of the trimpot though.

dv8r601 · Post by **dv8r601** » 11 Jun 2017, 23:47

Yeah that is what I was thinking, I know I've seen this setup before. The dual opamp and a 555 oscillator and the 386 for drive/ fuzz. In any case if I run back across A working schematic I'll pop it up. I can't help much on color codes until I get to A proper pc monitor, you can't measure them unless you desolder them. Also A 1.2k pot is a bit odd but I have seen stranger things. I have a ton of iskra 222(2.2k) pots but not 122. I'll bet the others here can look and tell you exactly what this is.

mirosol · Post by **mirosol** » 12 Jun 2017, 17:44

Not sure what the dual does here, but rest of it seems to be pretty much Escobedo's Ugly Face.
http://experimentalistsanonymous.com/di ... lyface.gif
+m

moidphotos · Post by **moidphotos** » 12 Jun 2017, 23:31

Thanks dv8r601 - I realised that trying to measure the colour values of the resistors under the orange light of artificial lighting was a bad idea, so I relit the board with white light and took more photos and used the colour picker in Photoshop to work out the band colours, then asked my wife to check a few for me... I think I now have a new way of checking resistors

I've redrawn part of the board (see below) in case that is of interest. I've tried to draw a schematic from this (which is damn hard!) and I'm attempting to breadboard it...

Thanks Mirosol, I think you're right - the circuit has a lot in common with an uglyface, and now I've listened to some demos of the uglyface I can say it sounds similar too. The main differences would be it lacks the gated sputtering out of the notes that the uglyface has (possibly this is what the extra op amp is for - to get more sustain?) and it's not as harsh sounding a fuzz; it's slightly smoother. I think I will try to breadboard it anyway and then maybe add in some of the mods from the uglyface to see what I can come up with