Author Topic: Powering LEDs externally (Read 182 times)

neyman · « **on:** June 19, 2009, 02:51:13 PM »

Can anyone give me a tip on how I can rig up a battery box to run the LEDs on my Series II (without a power supply, that is).

The plan is to run the pickup with the onboard batteries (2 9v), and run the LEDs through the 5 pin jack via external batteries. The problem I'm having is which pin powers the LEDs. Pin 4, 5, or both?

Or can this even be done?

Bradley Young · « **Reply #1 on:** June 22, 2009, 03:58:15 PM »

http://club.alembic.com/Images/449/8450.html

Has more info, but I don't know if the LEDs are powered off of the positive or negative or both side(s).

mica · « **Reply #2 on:** June 22, 2009, 05:43:33 PM »

Here's the response from Ron via the Helpdesk inquiry of the same:

On the DS5 diagram posted on the Forum, pis 4 and 5 are labeled as +V and -V respectively. Does the 5 pin power the LEDs and the 4 pin the pickups?

no. power is balanced rail type. the instrument will operate from + 9V on pin 4 and - 9V on pin 5, since the op-amps can adjust over wide voltage ranges.

but the LED's are connected in series and require higher voltage, and for an external battery pack, + 18V on pin 4 and - 18 V on pin 5 will operate fine.

the DS5 power supply give around + 22V on pin 4 and - 22V on pin 5, but the four batteries work great for both LED and the op-amps.

Do I run the battery pack (4 9v batteries in series) to pins 4 and 5? Or run 2 9v (series) to pin 4 and 2 9v (series) to pin 5?

hook 2 9V batteries in series with the negative grounded (to pin 1) and the positive lead to pin 4.

hook another 2 9V batteries in series with the positive grounded (to pin 1) and the negative lead to pin 5.

neyman · « **Reply #3 on:** June 23, 2009, 08:03:16 AM »

Thanks so much! This will get me through those long, dark nights on stage until I can get a power supply.