Posted by Ian Carter 2 on 13/04/2018 19:11:58:
Malcom,
The equipment is for my Thames sailing barge, will be fitted with a sail winch and servo for the rudder. Surely you need a battery for the power supply.
As said earlier, in the boat it just needs the 4 or 5 cell AA pack and a switch harness.
Using AA NiMH, both transmitter and receiver batteries will want to charge at the same (low) rate, but if the transmitter has 8 cells and receiver 4 or 5, obviously they are different voltages. If using one charger to do both at the same time, it will need to be a bit special. At least having a way of preventing the two batteries "seeing" each other.
Having spent much of my working life messing with electric bits, I had a tendency to knock my own together. I used a cheap battery eliminator from one of the cheapo chains with a current limiting high wattage resistor inserted into one of its leads. Add an appropriate connector, repeat with another eliminator for the other battery, result two overnight chargers. I can't be very specific, because I did them over 15 years ago and the memory has fogged and it just sits there and works. Low cost chargers often say quote their voltage and say something like "300mA". They rarely say whether they have a circuit built in to limit them to that maximum, or whether the components inside start to overheat at that point. Quite often, they are the £1.99 eliminator with a different label and higher price.
A write-up on the NX 83 (sounds rather more classy than the £1.99 eliminator) here – https://www.logicrc.com/reviews/OFSNX83_RCMW_052011.pdf – One battery at a time, overnight charging. One at a time should not be a problem – the transmitter, when charged, should last for several sessions.