*best* LDR for Mutron III / Neutron circuit

Looking for a particular component or hardware part and you just cannot find it? Got comoonents surplus and want to get rid of it? Post it all here... No sales of working pedals, put these in the 'Seen for sale' section please.

Re: *best* LDR for Mutron III / Neutron circuit

Postby digi2t » 02 Oct 2014, 11:20

Here is my tutorial for rolling your own Vactrol for the Mutron. I used a clear bright white LED, and two Waitrony KE-10720 LDR's.

http://www.diystompboxes.com/smfforum/index.php?topic=95269.0

The only thing I recommend is that you match the LDR's. I took a piece of wood, drilled two holes at the lead spacing of the LDR, and set it in a vice, underneath a light source that I could control the intensity. Pop an LDR into the jig, ensuring that it's sitting flat against the wood, and pointing directly at your light source. Connect you DMM to the LDR leads. Set your light source to an intensity where you get somewhere in the neighbourhood of a 10K reading from the LDR, it doesn't have to be exact. Write the reading down. Now, pull that LDR out, and insert another one in it's place. Connect the DMM, and take a reading. Compare the reading to the first one.

Keep going, until you get two LDR's that are within 100, to 200 ohms of each other. The Waitrony's are dirt cheap, so buying 10 or 20 of them won't break your bank. Definitely cheaper than VTL's. You'll be able to match up several sets.


Link
No matter how many times I cut it, it`s STILL too short!

For this message the author digi2t has received thanks:
aishabag23 (14 Mar 2017, 14:50)
digi2t
Degoop Doctor
 
Posts: 247
Joined: 09 Feb 2011, 16:10
Has thanked: 50 times
Have thanks: 330 times

Re: *best* LDR for Mutron III / Neutron circuit

Postby rrroo » 14 Mar 2017, 10:23

I built the madbean version of this pedal. made my own LED/LDR. everything seemed to work in UP mode but not in DOWN mode. I found out that the bias voltage at op amp, defined by R18 and R19 is not optimal. if you replace these with a trimmer working as a voltage divider, you can dial in just the right filter sounds and the choise of LED/LDR is not that crucial.
rrroo
 
Posts: 22
Joined: 03 Oct 2011, 10:47
Has thanked: 0 time
Have thanks: 0 time

Previous

Return to Parts Sourcing & Trading

Who is online

Users browsing this forum: No registered users and 2 guests