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Vintage threads from the first ten years

Power question?

12/26/1999 1:54 PM
Joe	Power question? I have a older Boss Analog delay on my board. I've powered it with an a/c adapter(9v dc) & always had a little extra noise that I just lived with. Never realy understanding why Boss made different a/c adapters for different fx that all run on a single 9v battery. Well this morning I got gutsy & decided to track down the culptrit. After finding that it was with the delay, I took it apart & found that there was a ground loop type of thing going on. The a/c adapter jack had a different ground than the battery & signal ground, I eliminated the a/c by using a battery. & no noise! So I removed everything else from the chain & the LED was very dim with the adapter. So I realized that the a/c was for 12v. (I tracked a resistor & diode etc. in it's path & the ground from the signal path was allowing the led to light properly as long as another fx box was in the chain) Bottom line- I unsoldered the wire from the a/c jack & added a wire that goes to the 'other' ground & no noise. I've been learning this stuff on my own & with the help from folks here, & other sites. So why did Boss require a 12v for the a/c adapter. Thanks, Joe

12/26/1999 1:54 PM

Joe

Power question?

I have a older Boss Analog delay on
my board. I've powered it with an a/c
adapter(9v dc) & always had a little extra
noise that I just lived with. Never realy
understanding why Boss made different
a/c adapters for different fx that
all run on a single 9v battery.
Well this morning I got gutsy & decided
to track down the culptrit. After finding
that it was with the delay, I took it
apart & found that there was a ground loop
type of thing going on.
The a/c adapter jack had a different
ground than the battery & signal ground,
I eliminated the a/c by using a battery.
& no noise! So I removed everything else
from the chain & the LED was very dim with the adapter.
So I realized that the a/c was for 12v.
(I tracked a resistor & diode etc. in it's path & the
ground from the signal path was allowing the led to light
properly as long as another fx box was in the chain)
Bottom line- I unsoldered the wire
from the a/c jack & added a wire that
goes to the 'other' ground & no noise.
I've been learning this stuff on my own
& with the help from folks here, & other
sites.
So why did Boss require a 12v for the
a/c adapter.
Thanks,
Joe