Robert Leclercq wrote:

Was looking into coax of that size yesterday for an industrial

application. It doesn't go much higher than 2-3KV in breakdown
voltage. Not what you want. Robert

Try type N coax.

PauLamar

Is that a silicone insulated coax people? Otherwise the electrical
requirements may be met while the stuff melts in side the cowl.
Bill Jepson

I think you get it with teflon. Not exactly flexible :)

Paul Lamar

Matt Prather wrote:

The purpose of coax has been to convey high frequency signal power
between two RF devices.  The most important features are the matching
of impedance (for best power transfer), and picking a dielectric
media that reduces frequency dispersion (allowing higher frequency
content - bandwidth).

Yes, ideal ignition wires efficiently convey high power, but if high
frequency content is filtered out, all the better - the spark plugs
won't know the difference.  And it's this high frequency content which
gets into our AM VHF comm radios and strikefinders (if you are lucky
enough to have such a thing).  The filtering of high frequency content
from the ignition system is the reason for the helical wound wires.

As anecdotal evidence, if coax was better for horsepower, you would
see car's like Corvettes and RX8s with it.  Instead, they have gone
the smarter route and used very short sections of high tension wire
running from coil-per-plug ignition.  This is the best bet for custom
built aircraft too.  The shorter the wire, the less there is for
losses.

As further anecdotal data, I run MSD CDI igntion on my O-200 with fairly
long wires between the coils and the plugs.  I use Moroso helical wound
wire I bought at the local Schucks.  It works great, and makes less
ignition noise (by far) than the Bendix mag that runs the other set of plugs.

I'd say, save your neat-o, high dollar coax for running radios - use
RG400 for that.

Regards,

Matt-
VE N34RD, C150 N714BK

 
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