Boss HM-2 Power Problem

[Nocturno]

Hello,

my Boss HM-2 Pedal has a problem with the AC adaptor jack .  When using a Batterie everything works fine as it should do , but when I want  to use the AC jack with an adaptor , the status LED only lights up very weak and it seems that there isn't coming enough current through  to the circuit . The adaptor is OK !
What can be the prob ??

Stefan

[George Giblet]

I think what you are seeing is a typical problem on the older Boss effects.

The older boss effects are designed for the unregulated Boss ACA power supply which puts out about 12V - Boss allowed for this by the way.  When you use a regulated 9V supply the actual voltage getting to the circuit is somewhat lower than 9V.

The later Boss effects use the regulated 9V supply, the Boss PSA power supply.

One trick is to put another effect (anything but another Boss ACA type)  before , or after, the HM-2 and run both effects from the same supply.


[fixed ACA/PSA reversal]

[Nocturno]

Thanks for help.  How can i mod it  to accept  a normal , regulated 9v supply ?

[George Giblet]

See recent thread,

http://www.diystompboxes.com/smfforum/index.php?topic=49501.0

[Nocturno]

thanks ,  it  works !!   

I also  put a 1n4001 on the ac jack and connected the blue wire to it  for  polarity protection .
Sounds much better on  12 Volts as  on 9 i  think.

[343 Salty Beans]

Sounds much better on  12 Volts as  on 9 i  think.

Despite all the crazy notions of starving your pedals to get gnarly noises, most effects do