GhostriderBravo

Gentlemen. When my brother-in-law became disabled from strokes he gave me his airplane, flightbox and radio. The radio is a CIRRUS RC-7 EXCLL-7 Pulse Code Modulation radio. I bought a new Receiver and Transmitter batteries for the radio and plane because everything had been sitting up for some time. The engine was froze up. I have unfroze the engine and it runs great. it's a OS 46 MAX FX. Installed the two new batteries, all servos work great. Went to recharge both batteries with the charger, the Receiver battery charged but the Transmitter battery didn't charge. The battery was in the Transmitter and the charger was plugged into the Radio. The light on the charger was ON for the Receiver battery but not on for the transmitter battery. Anyone have any ideas why the Transmitter battery is not charging or who I can send the radio to and have it serviced.

larry@coyotenet

My Feedback: (21)

First check and see if the charger transmitter plug has voltage, if it is the phone jack type the wires can break inside the plug from bending. If you have voltage, which should be over 9.2 for most transmitter packs of that era, check and see if the internal jack on the transmitter has a broken connection. Also make sure the wiring to the battery has the correct polarity. Some transmitters had a diode in the charging circuit so they would not charge backwards, Futaba comes to mind. The charger should have the wires coded, usually the positive side has a white stripe, make sure your transmitter charge plug is wired similarly. On most systems the middle of the plug is positive, Futaba is reversed. If you are getting voltage to the charge jack of the transmitter and it is still not lighting the led on the charger it is possible the led is out and everything is still working. Most commonly the problem is a wire joint broken inside the insulation of the plugs. The way to see if that is the case is to pull on the plug and see if the wire stretches, if so it is broken inside the plastic and will have to have a new end installed on the wire.

GhostriderBravo

Thanks for the reply. The charger is a wall plug in type. It has 2 sets of wires. One set goes to the Transmitter plug. The other set of wires is a Black wire and a Black wire with a Red Stripe that goes to the Receiver. The other set of wires is also Black and the other wire is also Black but has a White stripe on it. I assume that it is the positive wire that connects to the inside of the plug and the Black wire is the ground wire and connects to the plug housing. This plug is round 3/8" long and plugs into the Radio Transmitter. My question is how do I check the voltage and the continuity of these wires. I will have to get back to you on the Radio transmitter plug and wiring tomorrow. I will have to pull the back off the radio to do see whats whats.

Stikum

Make sure the transmitter power switch is in the OFF position.