Music Electronics Forum

Go Back   Music Electronics Forum > Effectification > Guitar Effects

Reply

 

LinkBack Thread Tools Display Modes
Old 12-18-2006, 02:43 PM   #1
Senior Member
 
Join Date: Jun 2006
Posts: 170
BSIAB built...question on some strange voltages

I just built a BSIAB II using the PCB from General Guitar Gadgets. Schematic is here. The circuit works and sounds pretty good...the distortion comes on really quick but I used a linear taper 500K drive pot so that should explain that. All other values were per the layout/schematic except I used a 100ohm source resistor instead of 120ohm on Q3.

My question is on some slightly strange voltages on two of the trannies (based on the BSIAB II build instructions on the GGG site). Q3 has the exact same voltage on the source and drain (about 1/2 V+) with very low voltage on the gate. Q5 also has the same voltage on the source and drain (adjustable through the V+ range with the 100K trim-pot) with about 1.1v on the gate.

The unit doesn't sputter, it distorts pretty well...and a lot, tonality is good, it has plenty of drive and volume...plenty, and it decays well...no 'fizzing out' when a note decays.

Are these voltages anything to worry about? It does seem to work fine but I'd hate to not see the full potential because of some mistake/problem. Any help appreciated. Thanks.
Matt T. is offline   Reply With Quote
...and now, a word from our sponsor:
Old 12-18-2006, 03:59 PM   #2
Senior Member
 
Join Date: May 2006
Posts: 989
Probably best to ask that question at the diystompbox forum (http://www.diystompboxes.com/smfforu...php?board=2.0), where the overwhelming brunt of experienced BSIAB builders reside. They will be able to provide more assistance.
Mark Hammer is online now   Reply With Quote
Reply

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads

Thread Thread Starter Forum Replies Last Post
Traynor custom 40 low voltages Guitarist Maintenance, Troubleshooting & Repair 3 01-31-2007 11:14 AM
David Allen amps built for harp? hdawg Harp Amps 7 12-01-2006 11:48 AM
Strange output stokes Maintenance, Troubleshooting & Repair 8 11-23-2006 05:49 AM
Measured Zoom G9.2tt voltages Guitarist Theory & Design 0 11-04-2006 11:34 PM
Measuring voltages in a very high impedance circuit JC@ Theory & Design 4 07-04-2006 02:48 AM


All times are GMT +1. The time now is 08:00 PM.


Powered by vBulletin   Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO