This unit converts a servo signal to a switched forward - stop - backward function. "Nothing new" you might say. True.
But this one is made especially for the ballast tank of a submarine. It has some special features that make it well suited for this application:

• The microprocessor uses very effective filtering techniques to achieve a high reduction of unstable signals.
• A failsafe will bring the sub to the surface when the contact to the transmitter is lost.
• This failsafe can be delayed so that the trim of the boat keeps untouched by small interruptions.
• A water detector prevents diving when the sub is wet inside.
• A undervoltage monitor lets it surface when the bateries are empty.

Size 48x45x20 mm,  49 gram, no package, 
connector Graupner/JR,
comes with manual
Price:  	
BTS	€ 44,-

This Variation of the BTS has a feedback input and is configured as servo amplifier. The ballast system becomes proportional, that means the ballst tank moves parallel to you tansmitter stick. This gies you the best possible precission and comfort when bringing your model to neutral boyancy.

Failsafe, undervoltage and water sensor are the same as with the standart version.

with 30mm feesback potentiometer and  2 trim pots 
€ 49,-

SMD Version for the friends of small models.
25x23x14mm small and 10g light it can switch up to 1Amp .
Failsafe and watersensor like the big one but no undervoltage monitor..

Cable Graupner/JR 
€ 30,- 
servo version € 35,-