Nology

[jsg at donet.com]

| 	If Nology wires are not properly grounded, then you get get "excessive
| RFI". By proper grounding, I don't mean just bolting the ground straps to
| the most convienent point, but ensuring continuity as well. Was the
| installation even checked for continuity to ground? For some cars, Nology

properly grounded with braids... RF shielding simple doesn't work
that way. 

| They were all grounded at a single point on the head, and resistance from
| the braids to anywhere on the block, frame etc, never exceeded 0.05 ohms
| with a 4 lead sensing ohmmeter.
| As an experiment after the PCM was replaced, I placed an oscilloscope on
| the power antenna lead from my stereo.  With the stock wires, I had a clean

You can not measure RF impedance at DC as you found out. A shorted
transmission line 1/4 wavelength long will have an infinite
impedance. If you didn't know that, you would be surprised at what one
can do with a few ferrite cores and some coax. Also, keep in mind
that a slot in a large sheet of metal is an excellent radiator (a
complementary antenna). The techniques that you use to test (and
ground) at DC have little to no value at RF frequencies.

Two weeks ago, I tested an antenna for an impulse radar (3-4nS at 15kV
into 50 ohms) that I'm designing. That was able to make the display of
a digital camera flicker and crash a laptop. High power energy weapons
generally do not destroy electronics by the energy they radiate, but
rather by placing them into a state by which they destroy themselves;
i.e., turning on both transistors of a complementary transistor output
pair. Something like this could have easily ruined your car's ECM.

I've said too much (sorry) as neither this Nology nor the Spiralmax
topics are within the charter of this mailing list. I hope we can
quickly bring them both to a close.

john