What elements make a good Radio Frequency
(RF) ground system in a yacht?

Bart Senior

A counterpoise.



"N1EE" wrote in message
om...
What elements make a good Radio Frequency
(RF) ground system in a yacht?

Bart Senior

Mostly, hydrogen, oxygen, sodium, chorine and copper. In the right
proportions and places of course.

Cheers

N1EE wrote:

What elements make a good Radio Frequency
(RF) ground system in a yacht?

Bart Senior

What is the best way to make a counterpoise for
a boat?

"Gay Sailor" wrote

A counterpoise.


"N1EE" wrote

What elements make a good Radio Frequency
(RF) ground system in a yacht?

The simplest is a variable series LC circuit that tunes the ground path for
the lowest impedance possible.
A caveat though, the voltage across either element is the circuit Q times
the applied voltage. If you drive a 12volt Vcc amplifier (voltage swing of
24 volts) into a circuit with a Q of 10, there is 240 volts across the
series inductor and 240 volts across the series capacitor. So for your 12
volt output driver one would be wise to use 500 volt capacitors and
inductors.

Why not just convert your backstay antenna into a sleeve dipole? No ground
is necessary for this antenna, the radiation pattern is good and the
bandwidth is ok. I ran some NEC simulations on a 35 foot sleeve dipole over
a seawater ground and found the patterns and SWR to be quite good. If I get
a round to it I'll post the plans for such an antenna on a website. Any
engineer worth the title can look up a sleeve dipole on the net and figure
out how to build one too.

Swishy tither boy gay sailor!


"N1EE" wrote in message
m...
What is the best way to make a counterpoise for
a boat?

"Gay Sailor" wrote

A counterpoise.


"N1EE" wrote

What elements make a good Radio Frequency
(RF) ground system in a yacht?

http://www.arising.com.au/people/Hol...ph/counter.htm



"N1EE" wrote in message
om...
What elements make a good Radio Frequency
(RF) ground system in a yacht?

Bart Senior

Gilligan, you're way too nerdy for most of these people...

"Gay Sailor" wrote in message
link.net...
The simplest is a variable series LC circuit that tunes the ground path
for
the lowest impedance possible.
A caveat though, the voltage across either element is the circuit Q times
the applied voltage. If you drive a 12volt Vcc amplifier (voltage swing
of
24 volts) into a circuit with a Q of 10, there is 240 volts across the
series inductor and 240 volts across the series capacitor. So for your 12
volt output driver one would be wise to use 500 volt capacitors and
inductors.

Why not just convert your backstay antenna into a sleeve dipole? No ground
is necessary for this antenna, the radiation pattern is good and the
bandwidth is ok. I ran some NEC simulations on a 35 foot sleeve dipole
over
a seawater ground and found the patterns and SWR to be quite good. If I
get
a round to it I'll post the plans for such an antenna on a website. Any
engineer worth the title can look up a sleeve dipole on the net and figure
out how to build one too.

Swishy tither boy gay sailor!


"N1EE" wrote in message
m...
What is the best way to make a counterpoise for
a boat?

"Gay Sailor" wrote

A counterpoise.


"N1EE" wrote

What elements make a good Radio Frequency
(RF) ground system in a yacht?

That would be interesting, please do it.

Cheers
Gay Sailor wrote:

The simplest is a variable series LC circuit that tunes the ground path for
the lowest impedance possible.
A caveat though, the voltage across either element is the circuit Q times
the applied voltage. If you drive a 12volt Vcc amplifier (voltage swing of
24 volts) into a circuit with a Q of 10, there is 240 volts across the
series inductor and 240 volts across the series capacitor. So for your 12
volt output driver one would be wise to use 500 volt capacitors and
inductors.

Why not just convert your backstay antenna into a sleeve dipole? No ground
is necessary for this antenna, the radiation pattern is good and the
bandwidth is ok. I ran some NEC simulations on a 35 foot sleeve dipole over
a seawater ground and found the patterns and SWR to be quite good. If I get
a round to it I'll post the plans for such an antenna on a website. Any
engineer worth the title can look up a sleeve dipole on the net and figure
out how to build one too.

Swishy tither boy gay sailor!


"N1EE" wrote in message
m...

What is the best way to make a counterpoise for
a boat?

"Gay Sailor" wrote


A counterpoise.

"N1EE" wrote

What elements make a good Radio Frequency
(RF) ground system in a yacht?

Gay Sailor wrote:

A caveat though, the voltage across either element is the circuit Q times
the applied voltage. If you drive a 12volt Vcc amplifier (voltage swing of
24 volts) into a circuit with a Q of 10, there is 240 volts across the
series inductor and 240 volts across the series capacitor. So for your 12
volt output driver one would be wise to use 500 volt capacitors and
inductors.


Can you explain this. I though that for a parallel LC the impedence went
to infinite at resonance (f=1/2pi sqrt(LC)) so that Vin=Vout.

What am I missing?

Cheers

Nav wrote:

Can you explain this. I though that for a parallel LC the impedence
went to infinite at resonance (f=1/2pi sqrt(LC)) so that Vin=Vout.

What am I missing?

Getting beyond my knowledge (or memory), but Gilly did say that the LC
circut is series - would that work better?


--
Wally
www.artbywally.com
www.wally.myby.co.uk/music