A receiver pack which won’t let you down 

Receiver packs are often the last component most people worry about despite being the vital link in maintaining control of an expensive model  

A couple of things you should know about Nickel based rechargeables: 

·         New rechargeable cells don’t work  well on the first charge

·         Rechargeables loose up to a third of their potential if you charge the night before

·         As current demand (servo torque) rises voltage (servo speed) and capacity falls i.e. increasing the likelihood of glitching

·         Rechargeables perform better if you charge & discharge to .9v per cell using a light bulb every six months or so

·         Rechargeables should be discharged and then charged to 40% before storing for a month 

A new pack:  go for high discharge avoid unnecessary weight. 

·         5 cells rather than 4 cells will ensure you get significantly high voltage longer and under load and your servos will be faster with better torque 

·         Modern digital servos use a lot of amps. Choose high discharge cells rather than high capacity   

·         For competition an IB 1400 is a small high discharge cell. It weighs just 21 grams and packs 30 minutes of runtime to 4 large servos doing 3D. High discharge cells put out huge power before loss in capacity or voltage, are cheaper and charge in 30 minutes and top up in 10 

·         On a 4 kg 3D aircraft a 4 cell pack of IB1400s will give you a constant 5.2 volts and a 5 cell pack 6.4v over 20 minutes of flight 

·         For sport add a second pack of IB1400s or use GP2200’s. Full size sub c’s are simply lead in the saddlebags.      

·         A small field charger will let you charge in 30 minutes and top up in 10 from a  car battery 

·         In preparation for use charge and discharge the pack twice. This maximises pack voltage and capacity 

·         For ultra smooth power add a 5 or 6v output BEC like the Medusa units which will give you the exact voltage from go to wow without radio interference.  You can also tailor power output eg in a heli a 6.5v pack can run a 5v BEC feeding a gyro/servo while the other components benefit from the higher pack voltage or a 6v output BEC 

Using the pack:  

·         Charge as close to use as possible and top up between runs. A  field charger will charge IB1400 in 30 minutes and let you top up from a car battery in the time it takes to refuel.

·         Throw away radio on-off switches and use banana plugs on radio packs. These allow you to charge and discharge the pack in situ and make for ultra reliable pack connections and de facto on off switch.

·         When you finish for the day discharge the pack to .9v per cell  (eg 5 cells 5*.9 = 4.5v) using tail light bulb. Recharge the pack to approx 40% of capacity i.e. 15 minutes and store.

·         Charge and discharge (cycle) the pack every 6 months or so to maintain cell balance

When you go out next you will have a pack which will give ultra reliable performance and control for the life of the model.