I have a Hitec "Flash 5" transmitter which gives me bogus information about the battery voltage. It shows approx. 1 volt low, as I've tested the same battery with 2 different voltmeters, and for example, they show 10.3V where the tx voltmeter shows 9.3V. I was told that there's a way to adjust that in-unit voltmeter if I take the back off. Well, I took the back off, and I'll be dogged if I can find a hint of adjustment screws for anything electronic. Any suggestions as to what I can do?

Jackster,
Send it to Hitec for adjustment.
When you test the battery are you putting a load on it?
This may be causing the difference.
KW_Counter

Jackster00

KW_Counter's comment about applying a load is the key. You can not measure the voltage without a load and get the correct reading. When the Tx is on, the load is automatically applied. Either measure the voltage when the unit is on, or apply a load to the battery when it is checked.

If, on the other hand, you are checking it when the unit is on, then you do need to send it back.

KW and J_R are correct. I suspect you are comparing the transmitter readout (which is always transmitting, thus under load) with a voltmeter reading (battery removed, no load.)

If 9.3 is your fully charged number, however, I think it is a bit low. My Prism, fully charged, shows me about 10.1 or so. What charger do you use?

Good luck
Dave Olson

Yes, you are right about the no load condition when I'm testing with a voltmeter. However, when the battery is charged with the supplied small trickle charger for a day or longer, the max. reading I get on the readout is 11.2V. I also have a Hobbico Accu Cycle "Pro Series Plus" which I use to charge and/or cycle my batteries. It just seems like a very short time passes before the TX reading is down in the lower 9's.....only 3 or 4 10 min. flights. I might add that on that wall charger, I've put resistors in the leads for the TX and the RX, so it won't over-charge the battery if it's left connected for a considerable time as these cheap-o chargers are prone to do. It's been suggested to me to splice into the battey leads with an additional pair with which to check the voltage. That way I can check the battery under load with an outside voltmeter.

You may have a problem with the tx switch. I did. In my case all you had to do was push the switch just a little and the volts would go all over the place. Tx was sent to Hitec where they not only replaced the switch but the circuit board behind it as well. If that is the case with yours, I wouldn't think of using it until it was serviced. Just my .02