HELP! Trouble with 12v landscape power supplies to power RGB dumb strings

[charlottedad]

HELP!!!   I installed some RGB dumb strings in my community public space and was planning to power them using the 12v landscaping power that was already there.  SURPRISE!!  It did not work.

 

I tested the power and it appears to have 13V but my multimeter reads it entirely different (READS 0 on the main display and 13.8V approx. on the small display at the top) than the power supply I used during testing and set-up (READS 12V on main display). 

 

The unit installed is a Vista Professional Outdoor lighting MT-600 that appears to have plenty of wattage but the RGB strings do not light properly and are very dim.  I hope I did not screw up the controllers!!

 

Any help would be greatly appreciated as I am nearly out of funds and I am supposed to have this up and running by Thanksgiving.

[charlottedad]

OK.  did a little more investigating and it looks like these "power supplies" are really just transformers that convert 120 VAC to 11-15VAC.

 

Therefore, does anyone have a suggestion on how to convert the 12VAC to 12VDC to use with these RGB Strings?

[dgtlpro]

Full bridge rectifier rated to handle the amps.

[scubado]

You'll be better off with one of these:http://www.amazon.com/Universal-Regulated-Switching-Computer-Project/dp/B00D7CWSCG/ref=sr_1_12?ie=UTF8&qid=1384648130&sr=8-12&keywords=12v+power+supply

 

The transformers you have may not be enough current.