Boss guru’s.. dim LED when pedal is on..

[WillyW]

So my new to me 30+ year old Boss FT-2 has an extremely dim LED….

I reconfigured my board and now the LED is extremely dim. BUT the pedal otherwise functions properly.

the pedal is new to me and before I reconfigured the board I do not recall it being dim.

I have it by itself on a 100mah outlet now. I do not recall what outlet it was on prior, but it may have been daisy chained off the tuner with two other pedals off a 250 or 500mah outlet…

I have since tried 250mah and 500mah outlets with no change in the LED, and no change in function.

Is this something that can be fixed, and is it detrimental not to fix it?

and how do I fix it? I can wired up geetars with no problem but have no amp or pedal tinkering experience. (Well I fixed a cheapo comp once)

 

[HollowIdolEyes]

The FT-2 specifies a Boss ACA adapter, which supplies an unregulated 12V (as opposed to a PSA adapter, which supplies regulated 9V). Daisy chaining it with other PSA-spec pedals bypasses the ACA power requirement by virtue of a common ground--which is why it was functioning normally before. Putting it on an isolated 9V outlet by itself means it's now not getting nominal voltage, and it's the reason the LED is now dim.

Some Boss pedals work okay with the slightly lower voltage (e.g., BF-2), but the LED will be dim and they might have slightly lower headroom. Some won't work at all. If you want to restore the LED brightness while using an isolated 9V output, there is a diode and resistor you can remove and jumper that will essentially convert the pedal to PSA-spec. Otherwise, you'll need to keep it daisy chained with a PSA-spec pedal.

 

[WillyW]

The FT-2 specifies a Boss ACA adapter, which supplies an unregulated 12V (as opposed to a PSA adapter, which supplies regulated 9V). Daisy chaining it with other PSA-spec pedals bypasses the ACA power requirement by virtue of a common ground--which is why it was functioning normally before. Putting it on an isolated 9V outlet by itself means it's now not getting nominal voltage, and it's the reason the LED is now dim.

Some Boss pedals work okay with the slightly lower voltage (e.g., BF-2), but the LED will be dim and they might have slightly lower headroom. Some won't work at all. If you want to restore the LED brightness while using an isolated 9V output, there is a diode and resistor you can remove and jumper that will essentially convert the pedal to PSA-spec. Otherwise, you'll need to keep it daisy chained with a PSA-spec pedal.

awesome, thanks, I had not gone back to daisy chaining it.

I had heard tale of older pedals special power needs, I just didn’t realize I had one..

damn cool pedal….

I’ll remember to run it off the tuna from now on..

 

[WillyW]

I learned something new today… much appreciated @HollowIdolEyes

 

[BobKos]

I learned something new today… much appreciated @HollowIdolEyes

Me too! Thx!

 

[WillyW]

Found this… the video is no longer available, but lots of good info, I probably need to commit to memory since I seem to lika da boss peddles….

Correctly powering your old Boss pedal (ACA vs PSA simplified)

 

[WillyW]

Yeah baby!

daisy chained it with the oc-3 off of the tuna, and the light is back!

thanks again @HollowIdolEyes!

I still don’t understand the voodoo electronicle magic that made it work but I will make a sacrifice of buttered toast and jelly to chthulu to satiate his vengeance….

 

[tpaul]

I used to run those old Boss pedals off a 12v cordless phone power supply.

But yeah, running it from the tuner is the easiest solution.

 

[Mechayoshi]

I saw how old that was and immediately thought ‘ACA’. Personally so I avoid mixed voltage accidents I mod my vintage ones in a way that doesn’t remove/alter board components and is easy to reverse. (Look it up if unfamiliar, it bridges a yellow and blue wire essentially.)

Btw, lovely Boss collection!

 

[WillyW]

I used to run those old Boss pedals off a 12v cordless phone power supply.

But yeah, running it from the tuner is the easiest solution.

I am still running the tuna off a 250mah outlet, I usually run 2-3 pedals off it because I usually have more pedals than power supply outlets….

I saw how old that was and immediately thought ‘ACA’. Personally so I avoid mixed voltage accidents I mod my vintage ones in a way that doesn’t remove/alter board components and is easy to reverse. (Look it up if unfamiliar, it bridges a yellow and blue wire essentially.)

Btw, lovely Boss collection!

I’m going to research how to modify it, so far I have read it’s easy to do and reversible, I just haven’t found out how to actually do it…

I decided to go mostly Boss because I got tired of cutesy named pedals that don’t tell you what they actually do… “Monkey truck watermelon retread” doesn’t tell me what the pedal does…

AND I dislike those tiny silver buttons to turn the pedals on and off….

 

[WillyW]

Struck gold…

Modifying old Boss ACA pedals to PSA specs – stinkfoot.se

this one does not list the ft-2, but it lists another pedal that I own and sure enuff…

Convert Your Boss ACA Pedal to PSA - Stompbox Electronics

I think my habit of daisy chaining off the tuna saved me from discovering the aca conundrum sooner… -OR- it’s already modified…

FT-2 schematic

https://www.synthxl.com/wp-content/uploads/2020/04/Boss-FT-2-Schematic.pdf

OC-2 schematic

https://www.synthxl.com/wp-content/uploads/2020/04/BOSS-OC-2-Service-Notes.pdf

Now I just gotta learn how to read a schematic!

 

[WillyW]

 

[mmon77]

I decided to go mostly Boss because I got tired of cutesy named pedals that don’t tell you what they actually do… “Monkey truck watermelon retread” doesn’t tell me what the pedal does…

Truer words have never been spoken. And you gave me a good laugh, so thank you for that!

 

[WillyW]

I’m looking at methods of converting.

the best looks to be just jumping the diode and resistor WITHOUT removing them, from the back/bottom of the board, and it’s super easy to remove the jumper is desired… although I don’t see why it would need to be converted back to 12v….

I’m trying to figure out if my OC-2 is already converted… I’m not seeing the diode and resistor, so they may have been removed and jumpered, and I’m getting a bright light on 9v… Once I convert my ft-2 I think I’ll have a better understanding of what I’m looking at/for…

crap I hope I don’t start building my own pedals after this experience….

I decided I’ll make a label that says “converted to 9v PSA” but still retain the aca label just for coolness factor…

talk about shaging rabbit holes…

 

[WillyW]

D2 and R4 are sooper easy to identify on the FT-2, I’ll be done in a couple minutes once I assemble my soldering stuffs…


The OC-2 board will take a little more sleuthing…

R4 is the grayish under D2

 

[WillyW]

Ok the diode and resistor were well defined on the ft-2.

the diode on the oc-2 was defined but I had to follow the schematic (it was easier than I thought) to discern which was the correct resistor.

wildly different boards, but simple enuff…

I did jumper them from the back without removing the diode and resistor.

I tested the LED on a 9v power source and the ft-2 was brighter, and the oc-2 I don’t know if there was a real or imagined difference or none at all…

I’ll test function tomorrow…

I’ll still be daisy chaining as much as I usually do, this will just be one less thing to worry about…

OC-2 jumpered (right upper side)

FT-2 similar but different location….

 

[WillyW]

Both pedals tested, both pedals function perfectly.

There is a label maker at work and I’ll run off an amended power label for both.

By the way my power supply does have 12v capability, I just don’t want to have to remember which one to hook up where.

I will continue to daisy chain some pedals, but this will just eliminate any hassle…

the envelope filter does seem to function better overall, real or imagined….

I don’t detect any change in the oc-2’s normal awesomeness…

 

[WillyW]