ElectroDynamics Inc
Electronics and MORE for the Discerning Modeler!
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    EDR-103 Glow Drivers
      Single Cylinders & Twins
    EDR-105 Battery Monitor
    EDR-106 Pro Servo Reverser
EDR-107ADP Kill Switch
    EDR-108 Pow'R Back'R
    EDR-111 Pow'r Bus Pro
    EDR-117 LiteSys
    EDR-122+ Servo-Slo Plus
    EDR-124 BatMon Lite
    EDR-125 Gear Mg'R
    EDR-126 Gear Saver
    EDR-201 Current Probe
    EDR-203 ServoCiser
    EDR-206 Turbine Driver
    EDR-207L NanoTest
      Buffer-Amplifier Interface

    EDR-102 One-Clik
    EDR-103P Glowlite II
    EDR-107ADP Kill Switch
    SANYO eneloop Packs
    EDR-207L NanoTest
      A123 Tester

Ultra Switch II

    ED-Nano A123 Packs
    SANYO eneloop Packs
    Receiver Packs
    Transmitter Packs


    Switch Harnesses
    Amplifying Buffers
    Charge Cords

Festo Fittings


Heat Shrink Tubing

Ultra Precision Valves

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Tech Talk

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EDR-108 Pow'R Back'R

Double your SAFETY
Double your FUN
No Hassles!

The EDR-108 Pow'R Back'R uses two 6V Battery Packs and two Heavy-Duty Double-Pole Switches to provide Dual-Redundant security to your airborne system, just like in full-size aircraft.

With the EDR-108 Pow'R Back'R, you can tolerate a single failure (open-circuit, short-circuit, low voltage) in either battery pack, or switch, or battery wiring, without losing radio control.

The EDR-108 Pow'R Back'R continually monitors both battery packs and switches for the one with the higher voltage, and routes that to your Rx and servos.

You may combine different size packs. In practice, with two good packs, the EDR-108 draws power equally from both packs, adding their individual capacities.
I.e., if Battery #1 is a 6V/600mAH pack, and Battery #2 is a 6V/1200mAH pack, you will have an 1800mAH power supply onboard, with at least 600mAH to fly on, in case of a failure.  

Pow'R Back'R

Tech Note:

Our EDR-108 Pow'R Back'R is STILL the ONLY Redundant Battery system currently on the market that offers TRUE "ground isolation" between the two batteries. 

This means that you can safely use any multi-output charger, or, two DC field chargers connected to the same 12V field box battery, to charge your two redundant batteries thru the switch harnesses, hassle-free

Without this feature exclusive to the EDR-108, your chargers may become confused by the "common ground" between the batteries, and the batteries may end up being improperly charged.  We all know what THAT means!

Without our EDR-108?  The only safe way to charge those two batteries is to unplug one of them from the switch harness...  or, use two separate, single-output AC chargers.  What a hassle!


How much current can the EDR-108 handle?

The EDR-108 is capable of handling up to 6 Amps continuous DC, and 20 Amps pulse (20ms ON / 40ms OFF).  That's more than RC system wiring and connectors can handle.  RC connectors are rated to handle a max. of 3 Amps.

Doesn't the single output of the EDR-108 limit its maximum current?

Most RC receivers have only one battery port, so the standard EDR-108 has one output cable.  This does limit the total current that the RC system (receiver/servos) can handle.  If is possible, in most receivers, to supply power thru more than one port, e.g., thru the battery port plus an unused servo channel, since battery power in the receiver is internally routed (paralleled) to all servo outputs.

To take advantage of this, by popular request, we now offer a dual-output option, our EDR-108T, in all our packages, which allows the Pow'R Back'R to supply a full 6 Amps to the receiver/servos.

Just select Dual-Output EDR-108T in the ordering options below:


Pow'r Back'R with Standard switches


Pow'r Back'R with Standard Switches
Battery Monitor


Pow'r Back'R with Ultra Switches


Pow'R Back'R with Ultra Switches
Battery Monitor


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Orders: 1-800-337-1638; Info: (734) 422-5420; Fax: (734) 422-5338
31091 Schoolcraft Road; GAZ Commercial Center; Livonia, MI 48150