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Old August 18th 05, 11:04 AM
Stephen Parry
 
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Default Non-techie asks for help................

Hi folks, first let me apologise for not lurking, or even reading a
FAQ (I did look and did not find). I know that radio amateurs are a
helpful and friendly bunch, so here goes.
From the UK, for historical reasons, the BBC broadcasts programmes on
Long wave, specifically 1500 metres (198 Khz???). I drive a truck on
the continent of Europe, and would love to listen to this service
whilst on the road (for the cricket!). I know that the signal is
there, and of sufficient strength, as I can receive it OUTSIDE the
truck on an ancient "portable" Inside the steel box (cab) however, too
much noise/too little signal to be useful. The fitted radio has LW,
but again cannot be used for the noise. Could anyone please point me
to some answers to the following:
Antennae: Could I build (buy) some kind of antenna specifically to
receive this emission?
(My old radio has a socket labelled "AM antenna").
Could I build a receiver tuned only to this freq., with no need for a
speaker (run the sound in at headphone type power) that I could
hang/bolt outside the truck (on the roof?), with its own battery and
aerial? If so could someone point me to a diagram of such a beastie?
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Old August 18th 05, 12:59 PM
J. Mc Laughlin
 
Posts: n/a
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Dear Mr. Stephen Parry:
It is possible that the truck (it is one truck?) produces too much noise
at 198 kHz. An important test is to note if your portable radio tuned to
198 kHz receives a satisfactory signal-to-noise ratio when the truck is
running all of its equipment. Try placing the portable radio next to the
truck in places where one might attach an antenna.

The fitted radio, which has LW, must have an outside antenna. Is that
antenna in good condition?

Your solution might be to reduce the noise produced by the truck.
Antennas for LW suitable for mounting on a truck do exist, however they will
not help if they receive too much noise.

Let the group know the results of your testing. Tell us more about the
truck. Regards, Mac

--
J. Mc Laughlin; Michigan U.S.A.
Home:
"Stephen Parry" wrote in message
...
Hi folks, first let me apologise for not lurking, or even reading a
FAQ (I did look and did not find). I know that radio amateurs are a
helpful and friendly bunch, so here goes.
From the UK, for historical reasons, the BBC broadcasts programmes on
Long wave, specifically 1500 metres (198 Khz???). I drive a truck on
the continent of Europe, and would love to listen to this service
whilst on the road (for the cricket!). I know that the signal is
there, and of sufficient strength, as I can receive it OUTSIDE the
truck on an ancient "portable" Inside the steel box (cab) however, too
much noise/too little signal to be useful. The fitted radio has LW,
but again cannot be used for the noise. Could anyone please point me
to some answers to the following:
Antennae: Could I build (buy) some kind of antenna specifically to
receive this emission?
(My old radio has a socket labelled "AM antenna").
Could I build a receiver tuned only to this freq., with no need for a
speaker (run the sound in at headphone type power) that I could
hang/bolt outside the truck (on the roof?), with its own battery and
aerial? If so could someone point me to a diagram of such a beastie?



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Old August 18th 05, 04:54 PM
Richard Harrison
 
Posts: n/a
Default

Stephen Parry wrote:
"I drive a truck on the continent of Europe, and would love to listen to
this service on the road for cricket."

The Blau Punkt in my Karman Ghia got such signals all over the
continent, and I`m just one of millions.

Mr Parry did not say if his truck is Diesel powered as most European
trucks are. If so, he is free of his own ignition noise, usually the
hardest to suppress. He still may have alternator whine (perhaps a bad
diode) and he may have static discharges from things which rotate. Some
are under the hood, and their radiation should be kept under the hood by
the metal surrounding them. All such metal pieces should be bonded
together to keep the trap they form closed.

All conductors coming through or under the firewall should be well
grounded or bypassed with capacitors at the firewall. The exhausr pipe
may need bonding here also.

Maybe there is a gasoline powered rerfrigeration compressor generating
ignition noise. Standard resistance wires, capacitors, and bondibg
should silence that.

Springs can be used in wheel hubs to ground out static.

All the metal parts of the truck may have to be bonded together.

My Blau Punkt was equipped with a good sized choke coil in its battery
lead. It also had an internal "spark-plate" capacitor, and these rid the
power source of radio noise.

The telescoping antenna (about 50 years ago) could be extended to about
100 inches, which made the Karman Ghia quite a sight, but it worked. The
antenna cable was the standard high-impedance small inner-wire coaxial
type. This must be intact and perfect to keep the signal on track and
the noise out. Though German, it used Motorola connectors.

Radio frequencies decline very rapidly near their source. This is your
friend when the source causes interference. Keep the antenna away from
and shielded from sources of interferebce.

In 1935, Alfred A, Ghirardi (E.E.) wrote:
"---an aerial must be installed in (or on) the roof, under the running
boards or chassis of the car, or in some other locations.
---Considerable attention must be given to the ignition and other
electrical wiring of the car in order to eliminate all electrical
interference which it produces in the receiver."

Noise problems are more often caused by the vehicle than by the receiver
but some receivers may not be shielded and filtered well enough. If the
truck cab has its pieces bonded together and all pass-through conductors
are well bonded or bypassed, it should be electrically quiet. You should
be able to use a portable radio in there with proper placement or an
outside antenna.

Ghirardi devotes an entire chapter to automobile radio installation in
"Modern Radio Servicing". Car radios are hot in the summer months while
home radios are not.

Best regards, Richard Harrison, KB5WZI

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Old August 18th 05, 05:38 PM
Fred W4JLE
 
Posts: n/a
Default

Richard, can one drive far enough in Europe that the drive time would allow
listening to an entire cricket match? I mean here in the states it might be
possibe, say from New York to Texas etc...

"Richard Harrison" wrote in message
...
Stephen Parry wrote:
"I drive a truck on the continent of Europe, and would love to listen to
this service on the road for cricket."



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Old August 19th 05, 12:34 PM
Stephen Parry
 
Posts: n/a
Default


London - Vienna return more than enough!


On Thu, 18 Aug 2005 12:38:44 -0400, "Fred W4JLE"
wrote:

Richard, can one drive far enough in Europe that the drive time would allow
listening to an entire cricket match? I mean here in the states it might be
possibe, say from New York to Texas etc...

"Richard Harrison" wrote in message
...
Stephen Parry wrote:
"I drive a truck on the continent of Europe, and would love to listen to
this service on the road for cricket."




  #6   Report Post  
Old August 18th 05, 05:41 PM
Fred W4JLE
 
Posts: n/a
Default

As most modern big trucks are fiberglass, the bonding is moot.

"Richard Harrison" wrote in message
...
are under the hood, and their radiation should be kept under the hood by
the metal surrounding them. All such metal pieces should be bonded
together to keep the trap they form closed.

All conductors coming through or under the firewall should be well
grounded or bypassed with capacitors at the firewall. The exhausr pipe



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Old August 18th 05, 06:51 PM
Richard Harrison
 
Posts: n/a
Default

Fred, W4JLE raised a number of intresting points. DC to DC converters
are switching types to get high efficiency and this can generate many
harmonics. If not suppressed, as many converters are, this causes much
noise. The solution is to use the proper converter if required.

Yes England can be well received all over the European continent. The
transmissions are powerful and decline only about 6 dB every time
distance from the transmitter is doubled after the first 1.5 km from the
200 KHz transmitter.

The questioner referred to his truck cab as a "steel box". I accept his
word. However, I once had a Corvette with a fiberglass body. The
ignition system came well shielded and bypassed. The underside of the
hood was equipped with a fibergaass blanket for heat control and the
blanket was faced with aluminum foil for radio frequency control. It was
grounded. Trucks must use something similar if they have spark ignition
systems.

The Corvette`s Delco radio only had medium wave AM and VHF FM reception.
Both were satisfactorily quiet. Screams during acceleration and sudden
stops were the only disconcerting noises.

Best regatrds, Richard Harrison, KB5WZI

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Old August 19th 05, 04:29 AM
Crazy George
 
Posts: n/a
Default

Richard:

You should be advised that modern semiconductor driven diesel injectors are noisier than Kettering ignition systems.
DIN and the rest of the European regulatory bunch have really clamped down on spark fired ignition noise, but apparently
Diesels have escaped their attention.

--
Crazy George
The attglobal.net address is a SPAM trap. Please change that part to: attdotbiz properly formatted.
"Richard Harrison" wrote in message ...
Fred, W4JLE raised a number of intresting points. DC to DC converters
are switching types to get high efficiency and this can generate many
harmonics. If not suppressed, as many converters are, this causes much
noise. The solution is to use the proper converter if required.

Yes England can be well received all over the European continent. The
transmissions are powerful and decline only about 6 dB every time
distance from the transmitter is doubled after the first 1.5 km from the
200 KHz transmitter.

The questioner referred to his truck cab as a "steel box". I accept his
word. However, I once had a Corvette with a fiberglass body. The
ignition system came well shielded and bypassed. The underside of the
hood was equipped with a fibergaass blanket for heat control and the
blanket was faced with aluminum foil for radio frequency control. It was
grounded. Trucks must use something similar if they have spark ignition
systems.

The Corvette`s Delco radio only had medium wave AM and VHF FM reception.
Both were satisfactorily quiet. Screams during acceleration and sudden
stops were the only disconcerting noises.

Best regatrds, Richard Harrison, KB5WZI



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Old August 19th 05, 12:29 PM
Stephen Parry
 
Posts: n/a
Default

On Thu, 18 Aug 2005 10:54:21 -0500, (Richard
Harrison) wrote:
Thank-you Richard for the prompt reply, which I am afraid I understood
little of (! my fault not yours)


Stephen Parry wrote:
"I drive a truck on the continent of Europe, and would love to listen to
this service on the road for cricket."

The Blau Punkt in my Karman Ghia got such signals all over the
continent, and I`m just one of millions.

Mr Parry did not say if his truck is Diesel powered as most European
trucks are.

Yes Diesel power, so no HT coil, plugs, distributor etc
If so, he is free of his own ignition noise, usually the
hardest to suppress.

Ok.
He still may have alternator whine (perhaps a bad
diode)

Yes I think I do have alternator noise could you explain what I might
do ?
and he may have static discharges from things which rotate. Some
are under the hood, and their radiation should be kept under the hood by
the metal surrounding them. All such metal pieces should be bonded
together to keep the trap they form closed.

All conductors coming through or under the firewall should be well
grounded or bypassed with capacitors at the firewall. The exhausr pipe
may need bonding here also.

I think we might have been divided by our common language! My truck
has no "hood" as such
http://www.duet-duda.mojagielda.pl/?9

Maybe there is a gasoline powered rerfrigeration compressor generating
ignition noise. Standard resistance wires, capacitors, and bondibg
should silence that.

No 'fridge
Springs can be used in wheel hubs to ground out static.

I did not understand this part

All the metal parts of the truck may have to be bonded together.

Or this

My Blau Punkt was equipped with a good sized choke coil in its battery
lead. It also had an internal "spark-plate" capacitor, and these rid the
power source of radio noise.

Or this

The telescoping antenna (about 50 years ago) could be extended to about
100 inches, which made the Karman Ghia quite a sight, but it worked. The
antenna cable was the standard high-impedance small inner-wire coaxial
type. This must be intact and perfect to keep the signal on track and
the noise out. Though German, it used Motorola connectors.

Radio frequencies decline very rapidly near their source. This is your
friend when the source causes interference.

Sorry, this too!
Keep the antenna away from
and shielded from sources of interferebce.

When you say "bonding" I am guessing this means a clean earth return
to battery?

In 1935, Alfred A, Ghirardi (E.E.) wrote:
"---an aerial must be installed in (or on) the roof, under the running
boards or chassis of the car, or in some other locations.
---Considerable attention must be given to the ignition and other
electrical wiring of the car in order to eliminate all electrical
interference which it produces in the receiver."

Noise problems are more often caused by the vehicle than by the receiver
but some receivers may not be shielded and filtered well enough. If the
truck cab has its pieces bonded together and all pass-through conductors
are well bonded or bypassed, it should be electrically quiet. You should
be able to use a portable radio in there with proper placement or an
outside antenna.

Ghirardi devotes an entire chapter to automobile radio installation in
"Modern Radio Servicing". Car radios are hot in the summer months while
home radios are not.

Best regards, Richard Harrison, KB5WZI



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