BOSS PEDALS.....is this a circuitry bug?

[markv]

Some of my boss pedals; namely boss dd-3 & sd-1, turned on immediately once an adaptor was plugged. (while input jack has guitar cable plugged)
I believe that it should only turn on once you 'stepped' on the switch.


Help please..   

Is there a way to fix this issue?

thanks in advance! 

[JasonG]

Well
My guess would be that your using the wrong adaptor and you burnt out a diode. The power supply would be the only thing they both share. Measure the power supply. I once picked up a universal power supply. Used it for about a year. I was going to use it as the PS for my bread board. I took a dmm to it every setting gave me 13 V!

[markv]

no sir, i'm using boss adaptor & sometimes the gator psu.

On batteries.....it still does the same thing! 

[JasonG]

Well there are two boss adaptors ASA and PSA. The ASA was the first adaptor they made its higher voltage. I screwed up my Boss RV3 with that one . The salesman a local guitar store didn't know anything  and sold me the wrong adaptor .   
I would measure the adapters anyway. Like I said you could have gotten a bad one. You wouldn't know unless you measured it.
If you know the PS is good. Crack them open do a visual inspection if all is well , get out the dmm.

[markv]

i'm using a PSA boss adaptor. 

i just notice that this problem is common to all boss stompboxes (pedal automatically turns on via plug of adaptor)....a lot of guitarists i know are having this issue as well.


Is there a solution to this? 

[5thumbs]

Just to +1 on this issue...my DS-1 pedals turn on automatically when I plug in a PSA adapter while plugged into the input.  My other BOSS pedals (MT-2, SD-1, TU-2) do not do this, but both of my DS-1 pedals display the behavior that Mark is describing.  They also do this when using the Danelectro 9V adapters, so it doesn't appear to be just the PSA causing the issue.

FWIW, My DS-1 pedals are both post-1994 DS-1 pedals that were produced years apart (one gnarly, old one bought used and one bought new by me), so it isn't likely that a flaky batch of components caused this behavior in a subset of DS-1 pedals out there.  I've never investigated as to why this happens, so I don't have any suggestions or explanations as to why it occurs.

Miqbal has developed a near-exact copy of the DS-1 layout in his quest for a DIY DS-1.  It will be interesting to see if his layout using stock components (minus the SIP8 dual op amp...using DIP8 dual op amp) has the same problem.  If its a design-level problem, then his copy of a DS-1 should exhibit the same behavior.

[bonkdav]

i was at a friends show and he was jumping around on stage which caused the power supply to cut out (on beat) then kick in on beat with the next jump and when his boss delay turns on its on reverse delay mode every time so it gave a crazy effect and no one knew what was going on because he was several feet away from his board when it happened.

this is the only time i think this problem could be cool though, and its probably not good on the amp or possible to recreate.

[Rob Strand]

If you look at the boss circuits there is a flip flop made from transistors doing the switching.   In its ideal form the circuit is symmetrical and has two outputs.  The only reason why one side will power up on instead of other is part tolerances there is nothing specific in the circuit which forces one side to power up first.   If you want to force the issue you have to change one of the resistors so there  is  asymmetry.  Play with the base resistors, say  go up or down a value, or the load resistors.

[joegagan]

i have noticed this behavior with almost all pedals that have flipflop switching. i just assumed that was part of the design.

[The Tone God]

Is there a solution to this? 

Check out the "Lost In State" article at my site.

Andrew

[amz-fx]

As Rob said, the random selection of component values will make the flip-flop go one way or the other at startup.  There is a way to add a capacitor to give it a blip when you plug in the power and force it to always go "OFF".  I'll look into it.

regards, Jack