Power to TX from charger during play (no battery) - powering the tx from an adapter

[DennisDarby]

Howdy!
We have the serial port interface working for us and now were wondering if there were any issues with running the transmitter from a charger or another DC power adapter during play instead of relying on the batteries. We are worried it might cook something internally and just want a second opinion. Thank you for your advice!

Dennis and Jon Darby

[gregg3]

don't quote me here, but when i looked at my tx.
a futaba skysports t4vf.

it looked to me as though the on/off switch.
when in the on position, directed the power from the battery to the tx and open circuit the charger jack to the battery.

when in the off position, the switch directed the power from the charger jack to the battery but open circuited the tx.

so assuming i am correct, you either power up the battery from the jack.

or you power the tx from the battery. NOT both at once!

basically what i am saying is it doesnt look good.

a minor modification would overcome this issue but i'm not about to go into that.

perhaps just soldering the wires from your dc supply to the pins or terminals that the batteries go to may do the job.

i hear a 9.6v dc supply will do the job.
and ensure crystals are removed from tx as usual.

no responsibilty taken for advise given, if anyone can confirm or deny the above info please do so, gregg

[Mike Roberts]

Hi

I would not power a transmitter from a charger without batteries installed. The charger output has to be higher to drive current into the batteries.

Power from a regulated source would be fine. Please check powers supplies. Some nominal 9v supplies will push out 14v when on low load. The key is to look for a regulated supply. A 9v unit would be my preference. 8v would almost certainly work also (this is dropped to 5v internally and 3v is required for some regulators).

A further comment - If you operate your transmitter with the output stage disabled the current drain is likely to be 20-30ma and dry/rechargeable batteries will give many hours use.

I hope this helps.

Mike

[gregg3]

yes i would have to totally agree with mike.
do not use a charger as such.
find a good quality regulated power supply.

i just gave my tx and cable to an enthusiastic new modeller.
who will now not have to go thru the pain, time and money of the initial learning curve.
if only it was around when i didnt even know what CG was.
(why is my plane going up,down,up,down???haha)

this has to be the greatest little program i have come across.