Ok, as we all know the HL sound is an excellent rendition of a bag of marbles being dropped onto a tin tray. There is no way to change that as the sound is hard coded onto a chip. It's either put up with the racket or turn the sound off.
So, what to do?
Beier cards will do the trick, they are programmable, quality but cost as much if not more than full blown tank boards, so not a cheap option by any means.
I took a look around the web, and there are gift card type sound cards that you can record messages onto. If messages can be recorded then so can tank sounds. We are not talking state of the art here, just something different to the HL sound. Even a random track squeak would be better, with no engine noise.
Alternatively, using something like Audacity, an engine sound could be merged with a track squeak, so even with only one channel, you could have two sounds.
The cards allow various lengths of recordings, but we would only need 5 - 10 seconds on a loop. The amplifier output on these is tiny, about 0.5 watts, but a cheap amp can be had/built for a few pounds.
The recording and playback isn't a problem, but activating the sound while the tank is moving is?
I had a scout around and there is a motion sensor switch that will activate a circuit when it is moving. So, if this was mounted on a spring inside the tank, as long as the tank was moving, the sensor would bounce around and start the playback on the card. When the tank stopped, so would the sound (this is my biggest issue, stopping the sound when the tank stops, rather than have it carry on playing an entire recorded track).
There are other slightly more expensive cards, about £20 that have a host of features, and allow usb downloads of sounds etc, however, the spec sheet of these confuses the hell out of me. I do wonder though whether one of these can be configured to activate from a channel on the rx, or maybe from the motor drive leads as they only have current when the tank is moving. If the smoke unit stops when the tank is stationary, maybe that would do it.
Power for a board could either be a seperate battery, or from the 7.2v battery as long as a resistor or regulator was in place.
Now, am I barking mad, or is there someone out there with an understanding of electronics who knows for certain whether this set up would work?
Here are a few links:
http://www.maplin.co.uk/p/miniature-tilt-switch-fe11m
https://learn.adafruit.com/downloads/pd ... -board.pdf
http://www.radioshack.com/9v-recording- ... HnTi493TtR
Please try and keep your replies on topic, I am only interested in whether this type of system would work.
RobG
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