You can use the accessory receiver and mount it in the loco... they don't have very good range, about 30 foot max, and only work on track 1, frequency 1, but they will work. There are 2 outputs you could use to trigger the Dallee.
I went thorough several attempts to control the sound functions of various sound systems using an onboard accessory RX with a TE with only marginal results and gave that up over 10 years ago. Went to DCC instead.
The on board receivers designed for motor control do a better job than the on board accy RX does.
George, as you know the black art of radio control can be frustrating! Here are two power cars built with similar components.
The Evans power boxcar had a reliable and responsive radio range of 135 feet. The radio range of the 40 foot boxcar was very poor. I can only assume the placement of the antenna over the battery pack in the 40 foot car was the reason for its lack of range.
Back to gentlemen’s question, could he activate the Dallee sound board with reed switches and magnets?
I put the accessory receiver in my battery Mallet. Works pretty good. I usually run it on "Frequency 1, channel 9." Doesn't work on any frequency but 1, annoyingly.
Had awful range with the antenna stretched along the top of the boiler (inside), but when I wound it around a piece of card and stood it near the back, the range improved drastically. Now I can trigger the whistle (or moan on a Mallet) from quite a ways away.
Since my tender is full of batteries and receiver, I put it inside the boiler. I wonder what creative uses I can find for these other outputs.
See the soda straws inside the boiler? I ran the antenna through these, down to the cab, back to the smokebox, and back to the center. Didn't work at all. I wound it around an old credit card and stood it against the inside of the firebox, and it will respond some distance away. The steam dome fell off once, and just as I was about to glue it back on, I thought, "This might come in handy!" So I can lift the dome off and reach the volume control and program button.
Dallee makes an "automatic" version that will work off reed switches and track magnets. I've not seen one of those but the Dallee guy didn't think that it would sell.... but it does.
If the original poster wants to PLAY the whistle, then DON'T get an automatic version. In that case, some sort of remote control is needed
Dallee does make a remote control box and interface that inserts some kind of signal on the rails and allows the functions to be played. I know next to nothing about it though. He needs to contact Dallee with his questions on this system.
I have the dallee board made to work with the reed switches 'cause I wanted to play the whistle and bell. Changing it to Phoenix. Liked the small scale board better than the dallee, though it plays whistle and bell itself, not by control.