Papa: You will probably not be able to use it with your transmitter since most radios contain a diode that protects it from having damage done to it someway through the charging jack, but I am not really sure about the specifics. For the receiver battery, I would really recommend going up to your LHS and purchasing an adapter for the receiver battery, and it will make your battery testing much much easier(this is assuming that the tester did not come with a special wire for the receiver, but if it did, just plug it into the charging jack of the receiver battery. If you want to try out the tester with the prong like wires that come with the Voltmeter, just try to insert the prongs into the charging terminal on your battery, but it might be hard to get a reading that way.