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Old September 6th 05, 07:00 PM
Chris Mullins
 
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HU is head unit, or radio


"Richard Crowley" wrote in message
...
Frank wrote:
2) Should a "in-glass" rear winshield antenna be grounded to the car's
body? If so, from which end of the coax cable? (see Q 3)


Grounding an antenna completely defeats its purpose.
Is this also part of a defrosting heating element or such?

3) Does the expression "grounding the antena" (in the case of a glass
mounted antenna) be as simple as soldering a grounding wire from the
outside coax lead end that plugs into the HU to a metal ground of the
car? Or should it be done closer to the actual antena? SUch as at the
junction of the end of the coax and where the antenna starts...


The expression "grounding the antenna" is nonsense
in the absense of better colatteral information. If it is
just an antenna (and not part of a heater or something)
then "grounding the antenna" sounds stupid.

What/who/why is "HU"? If this is a part of the circuit
you are working on, you need to reveal the entire situation.
Otherwise, you will get misleading responses based on
guessing from thousands of miles away.

Here is more detail on my problem if this helps: inconsistent
FM reception ( static) with in-glass antenna where I use to get
crystal clear reception with old car.


In-glass antennas have never been noted for their good
performance. They are only popular because they are
easier for the auto manufacturers (and car washes). Many
people add a proper antenna after-market when they are
stuck with these things.

However, there is a twist to my problem: I noticed that the coax cable
(inner cable) from the HU is not truly connected to the antenna even if
it looks like it is. I tested it with a continuity tester and it is not.


If "HU" means Heating Unit or something, it seems likely
that the antenna lead is connected via a capacitor. The cap
would conduct RF voltage while appearing to be an open
circuit at DC (which is what your meter is using.)