DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: blooze_man on July 29, 2010, 06:26:16 PM

Title: Broken BF-2
Post by: blooze_man on July 29, 2010, 06:26:16 PM
I was hunting down circiut bends in my BF-2 (found a cool one) and for some reason my pedal no longer turns on, does not pass a bypassed signal and has a very audible ticking. I can only assume I shorted something while I was poking around with a wire. Any help is appreciated. Thanks.
Title: Re: Broken BF-2
Post by: RedHouse on August 12, 2010, 08:49:06 AM
Not to hijack this thread, but does anybody have the service file for the BF-2?

Not just the schematic (which I already have) but the other pages which show the setup of the trimmers and voltages?
Title: Re: Broken BF-2
Post by: Derringer on August 12, 2010, 09:56:33 AM
Quote from: RedHouse on August 12, 2010, 08:49:06 AM
Not to hijack this thread, but does anybody have the service file for the BF-2?

Not just the schematic (which I already have) but the other pages which show the setup of the trimmers and voltages?

this help?

"Adjustment procedure:

1.) Clock frequency adjustment:
Set MANUAL and DEPTH knobs to full counterclockwise. Connect an oscilloscope to TP-1 test point. Adjust VR7 for T=25us (40kHz). Rotate the MANUAL knob fully clockwise. T should be 2uS +/-20%.

2.) BBD bias:
Set DEPTH and RES. knobs full counterclockwise. Feed a 200Hz, sine wave, 0dBm signal into the INPUT jack. Connect the oscilloscope to Q3's emitter. While turning MANUAL across its entire rotation range, set VR6 for a clip-free waveform at the peaks.

3.) Resonance:
Set MANUAL, DEPTH knobs full counterclockwise and RES. knob full clockwise. Plug short circuit into INPUT jack. Connect OUTPUT jack to an amplifier and speaker. While touching a screwdriver to TP-2, set VR5 to the point where oscillation begins. "
Title: Re: Broken BF-2
Post by: Derringer on August 12, 2010, 09:58:15 AM
Quote from: blooze_man on July 29, 2010, 06:26:16 PM
I was hunting down circiut bends in my BF-2 (found a cool one) and for some reason my pedal no longer turns on, does not pass a bypassed signal and has a very audible ticking. I can only assume I shorted something while I was poking around with a wire. Any help is appreciated. Thanks.

the only advice I can give is to go back and check everything. Is the pedal modified now? Undo the modification and try to get it working stock again.

here's the info I used when I modded mine
http://www.hobby-hour.com/electronics/s/boss-bf2-flanger.php (http://www.hobby-hour.com/electronics/s/boss-bf2-flanger.php)
Title: Re: Broken BF-2
Post by: RedHouse on August 12, 2010, 10:02:09 AM
Quote from: Derringer on August 12, 2010, 09:56:33 AM
Quote from: RedHouse on August 12, 2010, 08:49:06 AM
Not to hijack this thread, but does anybody have the service file for the BF-2?

Not just the schematic (which I already have) but the other pages which show the setup of the trimmers and voltages?

this help?

"Adjustment procedure:

1.) Clock frequency adjustment:
Set MANUAL and DEPTH knobs to full counterclockwise. Connect an oscilloscope to TP-1 test point. Adjust VR7 for T=25us (40kHz). Rotate the MANUAL knob fully clockwise. T should be 2uS +/-20%.

2.) BBD bias:
Set DEPTH and RES. knobs full counterclockwise. Feed a 200Hz, sine wave, 0dBm signal into the INPUT jack. Connect the oscilloscope to Q3's emitter. While turning MANUAL across its entire rotation range, set VR6 for a clip-free waveform at the peaks.

3.) Resonance:
Set MANUAL, DEPTH knobs full counterclockwise and RES. knob full clockwise. Plug short circuit into INPUT jack. Connect OUTPUT jack to an amplifier and speaker. While touching a screwdriver to TP-2, set VR5 to the point where oscillation begins. "

Yes thanks. You wouldn't happen to have a scan of the doc would you?
(or that PDF that was going around on the internet a while back)
Title: Re: Broken BF-2
Post by: Derringer on August 12, 2010, 10:06:40 AM
I have two of these pedals, but bought them both used and neither came with the original papers

this is all I've got to go on

http://www.hobby-hour.com/electronics/s/boss-bf2-flanger.php (http://www.hobby-hour.com/electronics/s/boss-bf2-flanger.php)

but I see it shows where the test points are so you should be good

Title: Re: Broken BF-2
Post by: RedHouse on August 12, 2010, 10:13:55 AM
Quote from: Derringer on August 12, 2010, 10:06:40 AM
I have two of these pedals, but bought them both used and neither came with the original papers

this is all I've got to go on

http://www.hobby-hour.com/electronics/s/boss-bf2-flanger.php (http://www.hobby-hour.com/electronics/s/boss-bf2-flanger.php)

but I see it shows where the test points are so you should be good



That's perfect thanks, the diagram below the schem is from the other page of the service doc.

I used to have that doc up until a HD failure in my desktop PC (no backup of course), anyway thanks for the pointer.
Title: Re: Broken BF-2
Post by: Steve Newton on August 12, 2010, 01:11:01 PM
I have these 2 pages of the service manual. No idea if there are more and this is all i can find. But it does have details  of the calibration procedure on the second page.


  (http://img248.imagevenue.com/loc227/th_31123_bf2_service_pg1_122_227lo.jpg) (http://img248.imagevenue.com/img.php?image=31123_bf2_service_pg1_122_227lo.jpg)(http://img22.imagevenue.com/loc68/th_31130_bf2_service_pg2_122_68lo.jpg) (http://img22.imagevenue.com/img.php?image=31130_bf2_service_pg2_122_68lo.jpg)
     
Title: Re: Broken BF-2
Post by: RedHouse on August 12, 2010, 01:15:27 PM
Quote from: Steve Newton on August 12, 2010, 01:11:01 PM
I have these 2 pages of the service manual. No idea if there are more and this is all i can find. But it does have details  of the calibration procedure on the second page.


  (http://img248.imagevenue.com/loc227/th_31123_bf2_service_pg1_122_227lo.jpg) (http://img248.imagevenue.com/img.php?image=31123_bf2_service_pg1_122_227lo.jpg)(http://img22.imagevenue.com/loc68/th_31130_bf2_service_pg2_122_68lo.jpg) (http://img22.imagevenue.com/img.php?image=31130_bf2_service_pg2_122_68lo.jpg)
     

Very good Steve, thanks for that.