Futaba 6D, 6DN - Manual (Page 9)

NI-CAD BATTERIES AND RE-CHARGING
FP-4DN, FP-5DN, FP-6DN and FP-5 Transmitters are equipped with eight (8) pen-light type Ni-Cad batteries.
For the Receiver & Servos, Four (4) Ni-Cad batteries are provided in the set.
Prior to each usage Ni-Cad batteries should be charged for 12 to 15 hours. If they have not been in use for some
time, the batteries should be charged for about 20 hours before use. There is no harm if the charging time is
slightly exceeded.
When Ni-Cad batteries are completely charged, you can ordinarily expect about 100 minutes of use during a given
day, about 10 control sessions of 10 minutes each.
Normally Ni-Cad batteries will hold an average voltage however, after this given time period of use, the voltage
will drop suddenly so it is recommended that following 7 or 8 control sessions of use, a voltage check be made
without fail.
For charging the Ni-Cad batteries, connections should be made as shown in the Diagram.
8
For charging either TRANSMITTER only or RECEIVER, both 'A' & 'B' plugs must be plugged into Transmitter bottom as
shown in the above diagram.