David,
Perhaps it is best to check the following in this order for a field
check:
First check and ohm out your radio connections and coax attachment to
your antenna. Check out the coax that the center wire and outer shield
have no continuity.
If the antenna is buried in the rear, do the following:
Build a 10 foot coax cable jumper. Install your coax jumper lead to the
radio back.
Beg, borrow or buy a standard VHF metal antenna with a ground plane, or
make a ground plane from aluminum and bolt it too the antenna and
connect to the ground. Place the antenna on a bench
near the aircraft. OR
I have an Advanced Aircraft Electronics VHF - 5T spare in my shop for
this purpose.
The coax connector attached to this antenna needs no ground plane and is
made from carbon fiber and wire. It is just like the tape antenna in
principal, but I have yet to find a better easier to install antenna,
but that is an opinion, because all properly built and installed
antennas should be nearly equal.
To best test your integrity of the com system.
If the intercom is loud and clear then the intercom to jacks are OK.
The newer radios have transmit key indicators as does a separate
intercom which may also be in your system. Press the mic button and
look. If the transmit indicator appears, the hookup is OK as the mic hi
position is connecting to ground for the transmit signal. If the ground
used for the mic button is hooked up outside the back of the radio, you
may have a poor and noisy ground or ground loop.
Please check your electrical continuity and circuit output using the
temporary antenna by pushing the com and giving a test count and
observe the power meter then check your primary antenna. If you don't
have a power meter, don't despair. compare the output transmission using
a handheld or other nearby radio.
If it is the antenna, it is time to go shopping.
Again if the antenna is the problem, the fastest, easiest to install,
high performance antenna is the VHF 5T available through Aircraft
Spruce.
An excellent position if you have no access to the tail, is to install
it just behind the baggage bay as close to vertical as possible. Works
great even with a little curve.
As for the short antenna, that is most likely your Transponder antenna.
Again, test its continuity and ground plane as the short antenna has a
ground plane requirement for the whip antenna of about an eight inch
disk. Your ground plane may not have been installed.
Again Advanced Aircraft Electronics has an antenna if yours does not
work.
The small box may be a radio switching box. It may have been used for
Nav and Glide slope switching if there is a horizontal antenna or a com
switcher if the ELT antenna was also hooked to the com antenna. Hard to
tell without tracing out your com and reading the part number on the
box.
Regards,
Bud Yerly
Custom Flight Creations, Inc.
www.customflightcreations.com<http://www.customflightcreations.com/>
(813) 653-4989
----- Original Message -----
From: David Lewendon<mailto:davidlewendon@me.com>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Saturday, May 28, 2011 3:54 AM
Subject: Europa-List: Filser Radio problems
<davidlewendon@me.com<mailto:davidlewendon@me.com>>
I have a Filser ATR 600 VHF Com plus a separate Filser Mode S
Transponder. I am experiencing difficulties in transmitting and
although I can hear various ATC centers from a reasonable distance of
20 to 30 miles out I cannot get them to hear me until I am only 6 or 7
miles away.
My Europa does not have an external antenna and having looked in the
rear fuselage section there appear to be two coax type cables. One
goes to a black metal box approximately 4 inches long and 3/4 of an
inch square that is fixed to the upper side of the fuselage (about the
ten o clock position). The other cable disappears into the tail
section.
There is a small unpainted metal antenna about 2 inches long
protruding from the lower fuselage but this must be too short for a
VHF radio and does not have the small ball on the end like a
transponder aerial would have.
BTW, I have not checked the transmit button yet for a good connection.
Any clues pleas?
Thanks
David
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avigator?Europa-List>
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