In , "Randy" wrote:

snip
I thought that because the whine went away when I disconnected the coax that
the problem was not related to the power supply and one of those noise
filters would not be of much use.


You said the noise is not present on your broadcast radio, which tells me that
the noise isn't coming from the antenna. If the noise goes away when you
disconnect the coax then it must be being picked up by the coax shield. If the
coax shield were grounded then the CB would not hear the noise. Since the coax
shield is connected to the chassis of the CB, that means the CB isn't grounded
(by 'grounded' I mean an RF ground). The radio should be grounded by mounting it
directly to the metal chassis and using a very short negative power lead. The
noise filter helps prevent noise from any possible ground-loops or other RF
feedback paths.


My biggest obstacle is that this is a company truck. The CB, radio and TV
are all using these antennas thru some kind of combiner.


......yikes!


Running new coax
would mean drilling holes in the cab. I am not sure how my boss would feel
about this. If it were my truck I would rip it all out and start from
scratch but I must do the best I can with what I have.


Your boss wants you to deliver the payload in the shortest amount of time with
the least amount of hassles. To do your job well, local communication with a
good CB is -extremely- helpful, and almost essential for a long-haul driver.


The antennas are mirror mounts. I have been reading about grounding. I
thought that two antennas actually were better on the fiberglass vehicles
because they could create a ground plane between each other. My antennas use
a plastic insert to keep them from being grounded to the mirrors. If I
ground them would this short out the transmitter?


Dual antennas have no practical advantage over a single antenna in a mobile
installation. They do not create a ground plane between them, nor do they work
as a counterpoise to each other. They do look cool, but if I were you I would
just use one and avoid the hassle.

As for the antenna mount, the shield of the coax should be -well- connected to
the chassis (ground-plane), and the center conductor to the antenna. The plastic
insert is used to keep the two apart. If you disconnect the coax at the radio
and check it with an ohmmeter (center conductor to the shield), it should be
wide open; i.e, -not- shorted.


I appreciate your feedback Frank, I know that it is difficult to diagnose
something from a distance but I am willing to try anything except routing
new coax.


Don't spend -your- time or money -- convince your boss that you need a CB radio,
then get him to have his contracted radio shop do a proper installation. That's
what most trucking companies do, and I'm suprised your's doesn't.






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"Frank Gilliland" wrote in message
...
In , "Randy" wrote:

snip
I thought that because the whine went away when I disconnected the coax
that
the problem was not related to the power supply and one of those noise
filters would not be of much use.


You said the noise is not present on your broadcast radio, which tells me
that
the noise isn't coming from the antenna. If the noise goes away when you
disconnect the coax then it must be being picked up by the coax shield. If
the
coax shield were grounded then the CB would not hear the noise. Since the
coax
shield is connected to the chassis of the CB, that means the CB isn't
grounded
(by 'grounded' I mean an RF ground). The radio should be grounded by
mounting it
directly to the metal chassis and using a very short negative power lead.
The
noise filter helps prevent noise from any possible ground-loops or other
RF
feedback paths.


My biggest obstacle is that this is a company truck. The CB, radio and TV
are all using these antennas thru some kind of combiner.


.....yikes!


Running new coax
would mean drilling holes in the cab. I am not sure how my boss would
feel
about this. If it were my truck I would rip it all out and start from
scratch but I must do the best I can with what I have.


Your boss wants you to deliver the payload in the shortest amount of time
with
the least amount of hassles. To do your job well, local communication with
a
good CB is -extremely- helpful, and almost essential for a long-haul
driver.


The antennas are mirror mounts. I have been reading about grounding. I
thought that two antennas actually were better on the fiberglass vehicles
because they could create a ground plane between each other. My antennas
use
a plastic insert to keep them from being grounded to the mirrors. If I
ground them would this short out the transmitter?


Dual antennas have no practical advantage over a single antenna in a
mobile
installation. They do not create a ground plane between them, nor do they
work
as a counterpoise to each other. They do look cool, but if I were you I
would
just use one and avoid the hassle.

As for the antenna mount, the shield of the coax should be -well-
connected to
the chassis (ground-plane), and the center conductor to the antenna. The
plastic
insert is used to keep the two apart. If you disconnect the coax at the
radio
and check it with an ohmmeter (center conductor to the shield), it should
be
wide open; i.e, -not- shorted.


I appreciate your feedback Frank, I know that it is difficult to
diagnose
something from a distance but I am willing to try anything except routing
new coax.


Don't spend -your- time or money -- convince your boss that you need a CB
radio,
then get him to have his contracted radio shop do a proper installation.
That's
what most trucking companies do, and I'm suprised your's doesn't.




Just so I am clear about one thing .... In all of these articles that I
have been reading, when they talk about grounding the antenna, they are
referring to a RF ground (ground plane) and not a physical ground? If for
some reason the shield is not grounded would this be my problem?

My boss will not care that this unit has a whine. I am not sure he would
care whether it has a CB or not. I had to take the truck down to the shop
last week to get the steer tires balanced, I had to pay for everything. He
is not a bad guy ... just cheap!

The unit might not be grounded very good. It sits in an upper header
console, just strapped in not bolted. I will ground the unit and purchase a
noise filter then adjust my antennas.

I tried reading as many articles as I could but they all were saying the
same things and some of that I could not understand. I thank you for your
time. I will let you know if the problem persist after these changes.

Thanks again

You should be able to remove the plastic inserts where the antennas are
mounted. You may also have a problem with the splitter that allows the
stereo and TV to use the same antennas. Maybe you can use one antenna for
the CB and the other for everything else. As for the whine, I agree with
everyone else. Once the antennas are working properly, it may go away.

Chris
"Randy" wrote in message
...

"Frank Gilliland" wrote in message
...
In , "Randy" wrote:

snip
I thought that because the whine went away when I disconnected the coax
that
the problem was not related to the power supply and one of those noise
filters would not be of much use.


You said the noise is not present on your broadcast radio, which tells
me
that
the noise isn't coming from the antenna. If the noise goes away when you
disconnect the coax then it must be being picked up by the coax shield.
If
the
coax shield were grounded then the CB would not hear the noise. Since
the
coax
shield is connected to the chassis of the CB, that means the CB isn't
grounded
(by 'grounded' I mean an RF ground). The radio should be grounded by
mounting it
directly to the metal chassis and using a very short negative power
lead.
The
noise filter helps prevent noise from any possible ground-loops or other
RF
feedback paths.


My biggest obstacle is that this is a company truck. The CB, radio and
TV
are all using these antennas thru some kind of combiner.


.....yikes!


Running new coax
would mean drilling holes in the cab. I am not sure how my boss would
feel
about this. If it were my truck I would rip it all out and start from
scratch but I must do the best I can with what I have.


Your boss wants you to deliver the payload in the shortest amount of
time
with
the least amount of hassles. To do your job well, local communication
with
a
good CB is -extremely- helpful, and almost essential for a long-haul
driver.


The antennas are mirror mounts. I have been reading about grounding. I
thought that two antennas actually were better on the fiberglass
vehicles
because they could create a ground plane between each other. My
antennas
use
a plastic insert to keep them from being grounded to the mirrors. If I
ground them would this short out the transmitter?


Dual antennas have no practical advantage over a single antenna in a
mobile
installation. They do not create a ground plane between them, nor do
they
work
as a counterpoise to each other. They do look cool, but if I were you I
would
just use one and avoid the hassle.

As for the antenna mount, the shield of the coax should be -well-
connected to
the chassis (ground-plane), and the center conductor to the antenna. The
plastic
insert is used to keep the two apart. If you disconnect the coax at the
radio
and check it with an ohmmeter (center conductor to the shield), it
should
be
wide open; i.e, -not- shorted.


I appreciate your feedback Frank, I know that it is difficult to
diagnose
something from a distance but I am willing to try anything except
routing
new coax.


Don't spend -your- time or money -- convince your boss that you need a
CB
radio,
then get him to have his contracted radio shop do a proper installation.
That's
what most trucking companies do, and I'm suprised your's doesn't.




Just so I am clear about one thing .... In all of these articles that I
have been reading, when they talk about grounding the antenna, they are
referring to a RF ground (ground plane) and not a physical ground? If for
some reason the shield is not grounded would this be my problem?

My boss will not care that this unit has a whine. I am not sure he would
care whether it has a CB or not. I had to take the truck down to the shop
last week to get the steer tires balanced, I had to pay for everything. He
is not a bad guy ... just cheap!

The unit might not be grounded very good. It sits in an upper header
console, just strapped in not bolted. I will ground the unit and purchase
a
noise filter then adjust my antennas.

I tried reading as many articles as I could but they all were saying the
same things and some of that I could not understand. I thank you for your
time. I will let you know if the problem persist after these changes.

Thanks again

"Chris" wrote in message
nk.net...
You should be able to remove the plastic inserts where the antennas are
mounted. You may also have a problem with the splitter that allows the
stereo and TV to use the same antennas. Maybe you can use one antenna for
the CB and the other for everything else. As for the whine, I agree with
everyone else. Once the antennas are working properly, it may go away.

Chris

If I remove the plastic inserts from the antenna mount, will that create a
direct short when I am transmitting?

I believe the splitter could be the problem also, like I said earlier if
this my truck I would rip it all out and start from scratch. I did a little
work ... swr @ 2.1. I just transmitted 9 miles. Whine still there ...
might be louder.

I am still wondering what is actually causing the whine i.e. alternator,
fuel pump ....... maybe I need to look at the source of the whine rather
than the ability to filter it out?

The mounting bracket should be grounded to the truck and attached to the
coax sheild. There SHOULD be an insulator between the antenna and the
bracket so leave it there.

Chris
"Randy" wrote in message
...

"Chris" wrote in message
nk.net...
You should be able to remove the plastic inserts where the antennas are
mounted. You may also have a problem with the splitter that allows the
stereo and TV to use the same antennas. Maybe you can use one antenna
for
the CB and the other for everything else. As for the whine, I agree with
everyone else. Once the antennas are working properly, it may go away.

Chris

If I remove the plastic inserts from the antenna mount, will that create
a
direct short when I am transmitting?

I believe the splitter could be the problem also, like I said earlier if
this my truck I would rip it all out and start from scratch. I did a
little
work ... swr @ 2.1. I just transmitted 9 miles. Whine still there ...
might be louder.

I am still wondering what is actually causing the whine i.e. alternator,
fuel pump ....... maybe I need to look at the source of the whine rather
than the ability to filter it out?

In , "Randy" wrote:

snip

Just so I am clear about one thing .... In all of these articles that I
have been reading, when they talk about grounding the antenna, they are
referring to a RF ground (ground plane) and not a physical ground? If for
some reason the shield is not grounded would this be my problem?


Close. Whine is RF interference from the engine electrical system (and sometimes
other electrical devices like the fuel pump) and occurs on almost all vehicles.
The difference is that an engine compartment which is fully enclosed by metal
will shield the radio and coax from this noise (the noise can also pass through
the electrical system, but that doesn't seem to be your problem). If you have a
fiberglass hood, or if your coax passes through the engine compartment, the coax
must be grounded at the radio end or it will pick up this noise just like an
antenna.

An RF ground is both an electrical ground -and- a physical ground. It is a
low-impedance path for RF and is very dependent on the physical properties of
the connection. Usually, a good RF ground is any point where electricity can
easily take many different directions -- kinda like ****ing into a lake. Just
about any point on the chassis will be a good RF ground. A single wire to the
chassis is a better antenna than an RF ground. For example, if your radio is
grounded with a wire longer than just a few inches it will allow RF voltage to
develop on the radio chassis, and the radio effectively becomes part of your
antenna system. That makes it very suseptible to engine noise and other types of
RF interference that may be picked up by the coax shield (which is connected
directly to your radio chassis) or passed through the electrical system to your
power leads. So by RF grounding the radio (and therefore your coax) you are
shunting all that RF interference to ground so the radio doesn't have to deal
with it.

Not having a good RF ground at the antenna can screw up your SWR, but that's
about all. It's much more important to ground that radio!


My boss will not care that this unit has a whine. I am not sure he would
care whether it has a CB or not. I had to take the truck down to the shop
last week to get the steer tires balanced, I had to pay for everything. He
is not a bad guy ... just cheap!


If it's a business expense it should be paid for by the business.


The unit might not be grounded very good. It sits in an upper header
console, just strapped in not bolted. I will ground the unit and purchase a
noise filter then adjust my antennas.


The upper header console is a terrible ground if your roof is fiberglass. I
would recommend mounting it on the dash or the hump, close to the chassis. That
will require rerouting the coax, but at this point that seems unavoidable.


I tried reading as many articles as I could but they all were saying the
same things and some of that I could not understand. I thank you for your
time. I will let you know if the problem persist after these changes.

Thanks again





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"Frank Gilliland" wrote in message
...
In , "Randy" wrote:

snip

Just so I am clear about one thing .... In all of these articles that I
have been reading, when they talk about grounding the antenna, they are
referring to a RF ground (ground plane) and not a physical ground? If for
some reason the shield is not grounded would this be my problem?


Close. Whine is RF interference from the engine electrical system (and
sometimes
other electrical devices like the fuel pump) and occurs on almost all
vehicles.
The difference is that an engine compartment which is fully enclosed by
metal
will shield the radio and coax from this noise (the noise can also pass
through
the electrical system, but that doesn't seem to be your problem). If you
have a
fiberglass hood, or if your coax passes through the engine compartment,
the coax
must be grounded at the radio end or it will pick up this noise just like
an
antenna.

An RF ground is both an electrical ground -and- a physical ground. It is a
low-impedance path for RF and is very dependent on the physical properties
of
the connection. Usually, a good RF ground is any point where electricity
can
easily take many different directions -- kinda like ****ing into a lake.
Just
about any point on the chassis will be a good RF ground. A single wire to
the
chassis is a better antenna than an RF ground. For example, if your radio
is
grounded with a wire longer than just a few inches it will allow RF
voltage to
develop on the radio chassis, and the radio effectively becomes part of
your
antenna system. That makes it very suseptible to engine noise and other
types of
RF interference that may be picked up by the coax shield (which is
connected
directly to your radio chassis) or passed through the electrical system to
your
power leads. So by RF grounding the radio (and therefore your coax) you
are
shunting all that RF interference to ground so the radio doesn't have to
deal
with it.

Not having a good RF ground at the antenna can screw up your SWR, but
that's
about all. It's much more important to ground that radio!


My boss will not care that this unit has a whine. I am not sure he would
care whether it has a CB or not. I had to take the truck down to the shop
last week to get the steer tires balanced, I had to pay for everything.
He
is not a bad guy ... just cheap!


If it's a business expense it should be paid for by the business.


The unit might not be grounded very good. It sits in an upper header
console, just strapped in not bolted. I will ground the unit and purchase
a
noise filter then adjust my antennas.


The upper header console is a terrible ground if your roof is fiberglass.
I
would recommend mounting it on the dash or the hump, close to the chassis.
That
will require rerouting the coax, but at this point that seems unavoidable.


I tried reading as many articles as I could but they all were saying
the
same things and some of that I could not understand. I thank you for your
time. I will let you know if the problem persist after these changes.

Thanks again





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Actually the header is aluminum and part of the cab, not bolted or riveted.
After working with it today I feel the alternator is the primary problem.
Since I have no ignition and no whine with the key in the ON position (Fuel
Pump), the alternator seems to be the culprit. I have been reading about
installing a micro_farad capacitor between the alternator and ground in
order to steady the voltage thus reducing the whine. I understand the theory
but could use some feedback about the practical application.

I feel this might be my least time consuming and least expensive solution.

In , "Randy" wrote:

snip
Actually the header is aluminum and part of the cab, not bolted or riveted.


Then you might get a fairly good ground right there. Bolt the bracket right to
the aluminum and run the black power lead to one of the bracket bolts, cutting
the wire as short as possible (no longer than six inches should be fine).


After working with it today I feel the alternator is the primary problem.
Since I have no ignition and no whine with the key in the ON position (Fuel
Pump), the alternator seems to be the culprit. I have been reading about
installing a micro_farad capacitor between the alternator and ground in
order to steady the voltage thus reducing the whine. I understand the theory
but could use some feedback about the practical application.

I feel this might be my least time consuming and least expensive solution.


You could try that, too. Find yourself a 'motor run' (NOT a 'motor start')
capacitor of around 1 to 5 uF. They usually have tabs for terminals so you can
use crimp connectors, and they can be mounted just about anywhere with a cable
clamp. Mount it as close as possible to the alternator, or even right on the
alternator if possible. Run one wire to the output and the other to ground,
again keeping the wires as short as possible. The capacitor is not polarized so
it doesn't matter which terminal goes to ground.

But know that some regulators are messed up by putting a cap across the
alternator. If you screw up your engine, don't blame me.





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"Frank Gilliland" wrote in message
...
In , "Randy" wrote:

snip
Actually the header is aluminum and part of the cab, not bolted or
riveted.


Then you might get a fairly good ground right there. Bolt the bracket
right to
the aluminum and run the black power lead to one of the bracket bolts,
cutting
the wire as short as possible (no longer than six inches should be fine).


After working with it today I feel the alternator is the primary problem.
Since I have no ignition and no whine with the key in the ON position
(Fuel
Pump), the alternator seems to be the culprit. I have been reading about
installing a micro_farad capacitor between the alternator and ground in
order to steady the voltage thus reducing the whine. I understand the
theory
but could use some feedback about the practical application.

I feel this might be my least time consuming and least expensive
solution.


You could try that, too. Find yourself a 'motor run' (NOT a 'motor start')
capacitor of around 1 to 5 uF. They usually have tabs for terminals so you
can
use crimp connectors, and they can be mounted just about anywhere with a
cable
clamp. Mount it as close as possible to the alternator, or even right on
the
alternator if possible. Run one wire to the output and the other to
ground,
again keeping the wires as short as possible. The capacitor is not
polarized so
it doesn't matter which terminal goes to ground.

But know that some regulators are messed up by putting a cap across the
alternator. If you screw up your engine, don't blame me.





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-----== Over 100,000 Newsgroups - 19 Different Servers! =-----


Well I have learned a tremendous amount about whine in a CB in the last
week. I stopped by a shop today to purchase a capacitor that I was going to
place on the alternator and the tech said he could fix the problem for
twenty dollars. I watched him open the unit, desolder a capacitor and
resolder a larger one in its place, he then shorted a couple of connections,
probably tweaking the unit. I figure he was doing the same thing I was going
to do but he did it inside the unit. I can just barely hear the whine ...
well worth twenty dollars.

I want to thank everyone for taking time to help me ... I did learn a lot
and I might put it to use when I have more time.

P.S. You all leave poor old George alone. If you would quit fueling the
fire the fire would burn itself out. I do not know what started it but it is
very detrimental to this group.

"Randy" wrote in message
...

"Frank Gilliland" wrote in message
...
In , "Randy" wrote:

snip
Actually the header is aluminum and part of the cab, not bolted or
riveted.


Then you might get a fairly good ground right there. Bolt the bracket
right to
the aluminum and run the black power lead to one of the bracket bolts,
cutting
the wire as short as possible (no longer than six inches should be
fine).


After working with it today I feel the alternator is the primary
problem.
Since I have no ignition and no whine with the key in the ON position
(Fuel
Pump), the alternator seems to be the culprit. I have been reading
about
installing a micro_farad capacitor between the alternator and ground in
order to steady the voltage thus reducing the whine. I understand the
theory
but could use some feedback about the practical application.

I feel this might be my least time consuming and least expensive
solution.


You could try that, too. Find yourself a 'motor run' (NOT a 'motor
start')
capacitor of around 1 to 5 uF. They usually have tabs for terminals so
you
can
use crimp connectors, and they can be mounted just about anywhere with a
cable
clamp. Mount it as close as possible to the alternator, or even right on
the
alternator if possible. Run one wire to the output and the other to
ground,
again keeping the wires as short as possible. The capacitor is not
polarized so
it doesn't matter which terminal goes to ground.

But know that some regulators are messed up by putting a cap across the
alternator. If you screw up your engine, don't blame me.





-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----


Well I have learned a tremendous amount about whine in a CB

Not from Geo, but that's OK. He's useless, except for tax purposes.