Icom A6 issues - shocks, interference

I recently bought an Icom A6 transceiver for use as a crew radio, and
have discovered several issues with it. Perhaps someone can make
suggestions for improving the situation:

Shocks

My wife was driving the motorhome while I was flying. After about an
hour that included a few transmissions and replies, she got some
tingling, then a shock from the A6. She put it down, and a bit later,
tried it again, with the same result except even stronger. There was
some lightning a few miles away, and some occasional light rain.

The A6 was connected to an external 3/4 wave Rainco antenna, but the
radio was operating on it's own battery and not plugged into the
motorhome battery power. Our previous radio never shocked her in 24
years, but was always plugged into the cigar lighter socket, so I
suspect that might have something to do with it. Has anyone else had
shocks from handheld radios used this way?

Interference

We discovered the some new fluorescent lights in the basement ("troffer"
style) cause a lot of static on the A6 when it's used with the external
whip antenna on top of the house. With the lights off, the squelch can
be set to 2; with the lights on, it must be set to 14 or 15 avoid the
static.

The radio is normally plugged into an Icom CP-20 Cigarette lighter
cable, which is plugged into a 12 volt output/120 VAC input bench style
power supply; however, the static and squelch settings are the same when
it's use on it's battery only.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz

On 8/9/11 5:07 PM, Eric Greenwell wrote:
I recently bought an Icom A6 transceiver for use as a crew radio, and
have discovered several issues with it. Perhaps someone can make
suggestions for improving the situation:

Shocks

My wife was driving the motorhome while I was flying. After about an
hour that included a few transmissions and replies, she got some
tingling, then a shock from the A6. She put it down, and a bit later,
tried it again, with the same result except even stronger. There was
some lightning a few miles away, and some occasional light rain.

The A6 was connected to an external 3/4 wave Rainco antenna, but the
radio was operating on it's own battery and not plugged into the
motorhome battery power. Our previous radio never shocked her in 24
years, but was always plugged into the cigar lighter socket, so I
suspect that might have something to do with it. Has anyone else had
shocks from handheld radios used this way?

Interference

We discovered the some new fluorescent lights in the basement ("troffer"
style) cause a lot of static on the A6 when it's used with the external
whip antenna on top of the house. With the lights off, the squelch can
be set to 2; with the lights on, it must be set to 14 or 15 avoid the
static.

The radio is normally plugged into an Icom CP-20 Cigarette lighter
cable, which is plugged into a 12 volt output/120 VAC input bench style
power supply; however, the static and squelch settings are the same when
it's use on it's battery only.


Interference from florescent lights is not necessarily a surprise. There
are great LED choices out there.

BTW at least for the house there is a bit more you can do for lightening
protection e.g. see http://www.arrl.org/lightning-protection

Its not clear what exactly is going on with your RV. But worth checking
that there is a good ground between the antenna signal ground and
chassis ground. yeas I know you can get a ground loop, but I'd want the
antenna really grounded to the chassis where its mounted, not say having
a ground plane float relative to the chassis.

Darryl




Darryl

On 8/9/11 5:07 PM, Eric Greenwell wrote:
I recently bought an Icom A6 transceiver for use as a crew radio, and
have discovered several issues with it. Perhaps someone can make
suggestions for improving the situation:

Shocks

My wife was driving the motorhome while I was flying. After about an
hour that included a few transmissions and replies, she got some
tingling, then a shock from the A6. She put it down, and a bit later,
tried it again, with the same result except even stronger. There was
some lightning a few miles away, and some occasional light rain.

The A6 was connected to an external 3/4 wave Rainco antenna, but the
radio was operating on it's own battery and not plugged into the
motorhome battery power. Our previous radio never shocked her in 24
years, but was always plugged into the cigar lighter socket, so I
suspect that might have something to do with it. Has anyone else had
shocks from handheld radios used this way?

Interference

We discovered the some new fluorescent lights in the basement ("troffer"
style) cause a lot of static on the A6 when it's used with the external
whip antenna on top of the house. With the lights off, the squelch can
be set to 2; with the lights on, it must be set to 14 or 15 avoid the
static.

The radio is normally plugged into an Icom CP-20 Cigarette lighter
cable, which is plugged into a 12 volt output/120 VAC input bench style
power supply; however, the static and squelch settings are the same when
it's use on it's battery only.


Oh and it sounds like the florescent ballast is coupling via the AC
power wiring. That is something every eclectic guitar owner know about.
You may wan to see if you can power the radio from a different
electrical circuit in the house or look at swapping the ballasts used in
the florescent lights. They likely have poor quality electronic
ballasts. You can get low-interference electronic ones or go for
magnetic ballasts. Or some combination of all of the above.

Darryl

On 8/9/2011 7:50 PM, Darryl Ramm wrote:
On 8/9/11 5:07 PM, Eric Greenwell wrote:
I recently bought an Icom A6 transceiver for use as a crew radio, and
have discovered several issues with it. Perhaps someone can make
suggestions for improving the situation:

Shocks

My wife was driving the motorhome while I was flying. After about an
hour that included a few transmissions and replies, she got some
tingling, then a shock from the A6. She put it down, and a bit later,
tried it again, with the same result except even stronger. There was
some lightning a few miles away, and some occasional light rain.

The A6 was connected to an external 3/4 wave Rainco antenna, but the
radio was operating on it's own battery and not plugged into the
motorhome battery power. Our previous radio never shocked her in 24
years, but was always plugged into the cigar lighter socket, so I
suspect that might have something to do with it. Has anyone else had
shocks from handheld radios used this way?

Interference

We discovered the some new fluorescent lights in the basement ("troffer"
style) cause a lot of static on the A6 when it's used with the external
whip antenna on top of the house. With the lights off, the squelch can
be set to 2; with the lights on, it must be set to 14 or 15 avoid the
static.

The radio is normally plugged into an Icom CP-20 Cigarette lighter
cable, which is plugged into a 12 volt output/120 VAC input bench style
power supply; however, the static and squelch settings are the same when
it's use on it's battery only.


Interference from florescent lights is not necessarily a surprise. There
are great LED choices out there.

These are 2' x 4', 3 bulb units (five fixtures total) that fit in a
suspended ceiling (aka "troffers"). None of the other 15 or so two tube,
4' and 8' fixtures in the house cause interference, so I'm wondering if
these new fixtures aren't working properly, or just happen to use very
noisy circuitry. If they are defective I can get them replaced;
otherwise, I'm hoping there is a fix for far less than the LED equivalent!

BTW at least for the house there is a bit more you can do for lightening
protection e.g. see http://www.arrl.org/lightning-protection

We haven't had any problems in the 30+ years we've had a crew radio in
the house, so it's probably not worth doing anything. We rarely have
lightning here, and none of the other glider pilots has reported any
lightning problems.

Its not clear what exactly is going on with your RV. But worth checking
that there is a good ground between the antenna signal ground and
chassis ground. yeas I know you can get a ground loop, but I'd want the
antenna really grounded to the chassis where its mounted, not say having
a ground plane float relative to the chassis.

The antenna is a end fed 3/4 wave (about 2' of 1.5" aluminum tubing, and
4' of whip) with no ground plane and no grounding requirement. It's only
connection is a BNC connector near the bottom of the aluminum tube. The
antenna is mounted on the side of a fiberglass/plywood/foam core
motorhome (no grounding at all, as required by the instructions for it),
using a spring mount to the base of the antenna. About 16' of coax goes
from the antenna BNC to the Icom BNC.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

In article Eric Greenwell writes:
I recently bought an Icom A6 transceiver for use as a crew radio, and
have discovered several issues with it. Perhaps someone can make
suggestions for improving the situation:

Shocks

My wife was driving the motorhome while I was flying. After about an
hour that included a few transmissions and replies, she got some
tingling, then a shock from the A6. She put it down, and a bit later,
tried it again, with the same result except even stronger. There was
some lightning a few miles away, and some occasional light rain.

The A6 was connected to an external 3/4 wave Rainco antenna, but the
radio was operating on it's own battery and not plugged into the
motorhome battery power. Our previous radio never shocked her in 24
years, but was always plugged into the cigar lighter socket, so I
suspect that might have something to do with it. Has anyone else had
shocks from handheld radios used this way?


As I recall from the description of the antenna, it is a variant of a
j-pole, where the first 1/4 wavelength of the length is actually a quarter
wave impedance transformer in the bottom tube.

As such, it does not need a ground plane or ground at the base to function
as an antenna.

HOWEVER, it does need a ground connection at the base of the antenna tube
to prevent static charge buildup and coupling down to the radio.


You are describing operating a radio connected to the wire coming down from
a lightning rod, where the point concentrates electric field at the top.
Even without lightning, air blowing past it can pick up a static charge
capable of startling a person. (There is also precipitation static in
rain...)

The base of the antenna should be clamped to the metal body of the vehicle,
preferably a solid point (not the sheet aluminum body of a motor home). Be
sure to have a good connection.

While at it, a provision to tip it down flat to not stick up above the
vehicle when lightning is possibly in the area.


Aside from making a mess of your radio, and probably your motor home,
people are killed by lightning.



Interference

We discovered the some new fluorescent lights in the basement ("troffer"
style) cause a lot of static on the A6 when it's used with the external
whip antenna on top of the house. With the lights off, the squelch can
be set to 2; with the lights on, it must be set to 14 or 15 avoid the
static.

The radio is normally plugged into an Icom CP-20 Cigarette lighter
cable, which is plugged into a 12 volt output/120 VAC input bench style
power supply; however, the static and squelch settings are the same when
it's use on it's battery only.

Grounds matter here, too. Be sure the frame of the fixture is well grounded
to the green wire of the circuit. Some modern fixtures won't work at all without
it, so they are leaking something out there.


Alan

On 8/9/2011 10:40 PM, Alan wrote:
In Eric writes:

As I recall from the description of the antenna, it is a variant of a
j-pole, where the first 1/4 wavelength of the length is actually a quarter
wave impedance transformer in the bottom tube.

As such, it does not need a ground plane or ground at the base to function
as an antenna.

HOWEVER, it does need a ground connection at the base of the antenna tube
to prevent static charge buildup and coupling down to the radio.


You are describing operating a radio connected to the wire coming down from
a lightning rod, where the point concentrates electric field at the top.
Even without lightning, air blowing past it can pick up a static charge
capable of startling a person. (There is also precipitation static in
rain...)

The base of the antenna should be clamped to the metal body of the vehicle,
preferably a solid point (not the sheet aluminum body of a motor home). Be
sure to have a good connection.

Our motorhome, like most motorhomes, does not have a metal skin body;
instead, the body is a metal framework encased in "sandwich" panels
composed of fiberglass/plywood/foam core/plywood. It would be possible
to find the closest metal rib and run a wire to it; however, I'm
wondering if the same effect could be achieved just by plugging the
radio into the 12 V power socket, rather than powering it just from it's
battery (thus, no connection to the motorhome frame).

While at it, a provision to tip it down flat to not stick up above the
vehicle when lightning is possibly in the area.

We can already do this, but we'd like a solution that let's her use the
radio and extended antenna when I'm flying, especially when I'm flying
to a distant airport and she's bringing the motorhome and trailer.

Aside from making a mess of your radio, and probably your motor home,
people are killed by lightning.

We want to eliminate this possibility, of course! It does seem possible,
as I've never heard of anyone getting shocked like she did. This makes
me suspect it is something specific we are doing and can easily correct.

Interference

We discovered the some new fluorescent lights in the basement ("troffer"
style) cause a lot of static on the A6 when it's used with the external
whip antenna on top of the house. With the lights off, the squelch can
be set to 2; with the lights on, it must be set to 14 or 15 avoid the
static.

The radio is normally plugged into an Icom CP-20 Cigarette lighter
cable, which is plugged into a 12 volt output/120 VAC input bench style
power supply; however, the static and squelch settings are the same when
it's use on it's battery only.

Grounds matter here, too. Be sure the frame of the fixture is well grounded
to the green wire of the circuit. Some modern fixtures won't work at all without
it, so they are leaking something out there.

I'll check the grounding.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

Not sure what to say about the lightning thing. Jan had to be pretty
surprised...

It seems like the newer electronic ballasts cause quite a bit of radio
interference. My first unpleasant encounter was after rebuilding the
panel in my new shop. Late into the night it's time for a radio test &
nothing but static. Couldn't stop it with the squelch, etc. Damn...
Was sure something was wired incorrectly until I tried it the next morning
with the lights off. Bingo! The florescent lights are nice new high
quality with the small energy saver tubes, etc. Biggest change is that
now most florescents use electronic ballasts.

Craig



On Tue, 09 Aug 2011 19:59:48 -0700, Darryl Ramm
wrote:

On 8/9/11 5:07 PM, Eric Greenwell wrote:
I recently bought an Icom A6 transceiver for use as a crew radio, and
have discovered several issues with it. Perhaps someone can make
suggestions for improving the situation:

Shocks

My wife was driving the motorhome while I was flying. After about an
hour that included a few transmissions and replies, she got some
tingling, then a shock from the A6. She put it down, and a bit later,
tried it again, with the same result except even stronger. There was
some lightning a few miles away, and some occasional light rain.

The A6 was connected to an external 3/4 wave Rainco antenna, but the
radio was operating on it's own battery and not plugged into the
motorhome battery power. Our previous radio never shocked her in 24
years, but was always plugged into the cigar lighter socket, so I
suspect that might have something to do with it. Has anyone else had
shocks from handheld radios used this way?

Interference

We discovered the some new fluorescent lights in the basement ("troffer"
style) cause a lot of static on the A6 when it's used with the external
whip antenna on top of the house. With the lights off, the squelch can
be set to 2; with the lights on, it must be set to 14 or 15 avoid the
static.

The radio is normally plugged into an Icom CP-20 Cigarette lighter
cable, which is plugged into a 12 volt output/120 VAC input bench style
power supply; however, the static and squelch settings are the same when
it's use on it's battery only.


Oh and it sounds like the florescent ballast is coupling via the AC
power wiring. That is something every eclectic guitar owner know about.
You may wan to see if you can power the radio from a different
electrical circuit in the house or look at swapping the ballasts used in
the florescent lights. They likely have poor quality electronic
ballasts. You can get low-interference electronic ones or go for
magnetic ballasts. Or some combination of all of the above.

Darryl


--
Using Opera's revolutionary email client: http://www.opera.com/mail/

On Aug 10, 10:07*am, "Craig Funston"
wrote:
Not sure what to say about the lightning thing. *Jan had to be pretty *
surprised...

It seems like the newer electronic ballasts cause quite a bit of radio *
interference. *My first unpleasant encounter was after rebuilding the *
panel in my new shop. *Late into the night it's time for a radio test & *
nothing but static. *Couldn't stop it with the squelch, etc. *Damn... * *
Was sure something was wired incorrectly until I tried it the next morning *
with the lights off. *Bingo! *The florescent lights are nice new high *
quality with the small energy saver tubes, etc. *Biggest change is that *
now most florescents use electronic ballasts.

Craig

On Tue, 09 Aug 2011 19:59:48 -0700, Darryl Ramm *
wrote:









On 8/9/11 5:07 PM, Eric Greenwell wrote:
I recently bought an Icom A6 transceiver for use as a crew radio, and
have discovered several issues with it. Perhaps someone can make
suggestions for improving the situation:

Shocks

My wife was driving the motorhome while I was flying. After about an
hour that included a few transmissions and replies, she got some
tingling, then a shock from the A6. She put it down, and a bit later,
tried it again, with the same result except even stronger. There was
some lightning a few miles away, and some occasional light rain.

The A6 was connected to an external 3/4 wave Rainco antenna, but the
radio was operating on it's own battery and not plugged into the
motorhome battery power. Our previous radio never shocked her in 24
years, but was always plugged into the cigar lighter socket, so I
suspect that might have something to do with it. Has anyone else had
shocks from handheld radios used this way?

Interference

We discovered the some new fluorescent lights in the basement ("troffer"
style) cause a lot of static on the A6 when it's used with the external
whip antenna on top of the house. With the lights off, the squelch can
be set to 2; with the lights on, it must be set to 14 or 15 avoid the
static.

The radio is normally plugged into an Icom CP-20 Cigarette lighter
cable, which is plugged into a 12 volt output/120 VAC input bench style
power supply; however, the static and squelch settings are the same when
it's use on it's battery only.

Oh and it sounds like the florescent ballast is coupling via the AC *
power wiring. That is something every eclectic guitar owner know about. *
You may wan to see if you can power the radio from a different *
electrical circuit in the house or look at swapping the ballasts used in *
the florescent lights. They likely have poor quality electronic *
ballasts. You can get low-interference electronic ones or go for *
magnetic ballasts. Or some combination of all of the above.

Darryl

--
Using Opera's revolutionary email client:http://www.opera.com/mail/

The tingling and mild electric shocks are caused by corona discharge
from the top of the antenna. Corona discharge is a pulsed electric
discharge from elevated conductors under the influence of high
atmospheric electric fields (typically 10kV/m). Such high fields
occur around shower clouds, especially thunderstorms. In extreme
conditions, the discharge will become visible as a glow (St. Elmo's
fire). Corona currents charging the capacitance of a coaxial cable
attached to an antenna can increase the amount of stored energy and
give a decent kick.

While not normally dangerous, the discharges involve high voltages
(you get sparking) and can damage sensitive electronics.

Antennas that are inherently grounded (such as the J-pole) are best
for these applications, but some designs use an ungrounded loading
coil that are more susceptible.

Mike

On 8/10/2011 10:07 AM, Craig Funston wrote:
Not sure what to say about the lightning thing. Jan had to be pretty
surprised...

It seems like the newer electronic ballasts cause quite a bit of radio
interference. My first unpleasant encounter was after rebuilding the
panel in my new shop. Late into the night it's time for a radio test &
nothing but static. Couldn't stop it with the squelch, etc. Damn... Was
sure something was wired incorrectly until I tried it the next morning
with the lights off. Bingo! The florescent lights are nice new high
quality with the small energy saver tubes, etc. Biggest change is that
now most florescents use electronic ballasts.

According to some industry publications, the T8 bulbs (the skinny ones)
are more energy efficient than the older T12 design, and some of that
comes from the high frequency (20 kHz to 60 kHz) electronic ballast they
use. The waveform is relatively noisy (20% or so total harmonic
distortion) compared the old style magnetic ballast, and even to the
electronic ballast used in some T12 fixtures.

Ballasts with improved waveforms and more filtering (less than 5% total
harmonic distortion) are available for facilities that need them, but at
a higher cost.

For my situation, it's no longer as interesting to my wife to be able to
hear my every word on the radio now that we're using Spot. If she wants
to talk to me, she'll turn off that set of lights (one wall switch),
reset the squelch, and then transmit.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz