ORIGINAL: Disposable Hero
Yes it will work with any of the Heng Long boards. Then you will need two 9.6v packs(i run 600mah which should give you a couple hours of sound at least).As far as a speaker you'll need a 15watt 8 ohm speaker and your all set(welsh dragons sells a nice one in a nice sealed box for $50) thats small enough to fit into just about any tank..
I guess what confussed me was where it said any variable switchable power source between 4 & 10 volts would operate the "Relay".....? So I'll assume the relay is what gives the variable sound affect.........but does not have anything to do with the power that drives the sound unit itself thus why you need the two additional batterys for that.
$50.00 dollars seems awfull high priced for a small speaker............But then i don't really know very much about speakers,and in this case maybe you get what you pay for when it comes to the sound quality.??
BIGMIG
P.S. I thought this unit may work straight off a 12 volt acid battery like in a stuart tank,but maybe that is still not enough power to get the desired sound.?