This 6" long servo extension, is fabricated of twisted, 20AWG stranded copper wire, has silicone insulation, and gold-plated connectors. Weighing 4g, with an overall length of about 8", the 6" (150mm) nominal length
refers to the approximate length of wire length between the connectors. Terminated with male and female ABS plastic JR-type universal radio connectors,
the extensions have a silky feel because of the silicone
jacket, which remains supple even at low temperatures. The actual metal
pins are gold-plated to preclude tarnishing (and for minimal contact
EDU: Digital servo extensions are widely available on the
market in gauges ranging from 20-28AWG (20 gauge wire is thicker than 28
and is rated to carry more current). The extensions may be stranded or
twisted and the jacket material is usually PVC or silicone. Twisted
wires resists RFI better (radio frequency interference) than flat wires
(e.g. stray signals from GPS, telemetry, electronic ignitions, etc.)
and silicone is usually a bit heavier, but significantly more flexible
and relatively unaffected by cold.
The supplied ABS plastic connector bodies are JR-type (universal),
with spacing of 0.10" (2.54mm) as found in headers throughout the
electronic world. The male/female metal pin-connectors themselves may be
tin or gold-plated to resist corrosion with gold being the more
expensive. The rated 5A continuous current capability isn't a function
of the extension wire but of the pin-connectors themselves, so they're
the weakest link.
ProTip: if you don't have the ability to measure current
through the extension, using an inexpensive IR (infrared) temperature
gun to check the temperature at the connectors (to see if they're a lot
hotter than the wire extension itself) is a crude but practical and
useful way to help judge for danger of overloading the individual servo
More experienced modelers tend to use extensions thicker than the servo
leads because this minimizes the voltage drop due to the added length of
wire (the extension itself) between servo and receiver. If you'd like to learn more about digital servo extensions (to include
calculations for voltage drop), this brief article will help guide you through
the math involved regarding gauge selection complete with some practical
Summary: one gauge heavier than the servo lead is a
good rule of thumb. Also, 20AWG is about the heaviest you can install
within a standard servo connector - this makes the 20AWG heavy duty extension
something of a no brainer!
- Length: 6" (150mm)
- Overall length: 8"
- Weight: 4g
- Current (max): 5A continuous
- Conductor: stranded copper
- Gauge: 20AWG
- Jacket: silicone
- Connectors: JR-type (universal)
- Material: ABS
- Plating: gold
There are experienced modelers who prefer to eliminate connectors and make up their own extensions. They'll whip out a roll of bulk wire, a crimping tool and connectors (plus solder, an iron, and heat shrink tubing). They'll skillfully make extensions customized to their model in a matter of an afternoon. They'll have fun, gain satisfaction of a job well done, maybe save a little money, and it's called modeling for a reason!
Yes, ditching the extra connectors reduces resistance a tiny bit. Eliminating a few inches of wire here and there also adds up to less resistance. Can you measure it when the job is done? In theory, yes. In practice, it's reasonable to wonder; are there pilots who can feel the difference the slight reduction in resistance delivers? Perhaps amongst those who have been gifted by God himself are some who will say yes (maybe). As for the rest of us (mere mortals), only you know if you're in this class but we're reminded of what Callahan said as Dirty Harry in Magnum Force
"A man's got to know his limitations."
The point is, it's our opinion the exercise of minimizing connections and optimizing wire length is akin to mental masturbation. Why? If for no other reason than because in their quest to do the best possible installation (by soldering and manually crimping the connectors) there's added human error at each crimp and solder joint. And as we all know, only God is perfect. Anyway, we confidently offer these heavy duty 20AWG extensions as a quick and easy solution for placing a servo remotely with greatly reduced effort.