Sorry to disappoint you John.

Nobody has ever made a significant improvement using aligator clips,
lengths of wire and baluns on a portable whip receiver. Except, if
lucky, merely by chance on one band at the expense of the others.

You may, however, hear a bunch of claims, e.g., by CB-ers and
plagiarising old-wives, based on imagination and wishful thinking.

Signal to noise ratio is what matters. And that's an uncontrollable
function of the incoming signals and noise. the ionosphere, and of the
receiver itself.

However, it's quite interesting to experiment with longer antennas.
Obtain a circuit diagram of the receiver and try to predict what will
happen - if anything.

A most elementary circuit analysis is all that's needed. Otherwise you
will be working entirely in the dark.

Clear your head and forget about a balun. You must have been reading
the wrong magazines articles. You are dealing with an
unbalanced-to-unbalanced, very high impedance-to-high impedance
situation.

Consider a ground conection to the receiver chassis. This lowers the
impedance to more predictable values. OK if you are located
conveniently near to a domestic plumbing system. But even a short rod
in good soil will have some effect for either better or worse.

If you insist, signal to noise ratio MIGHT be improved by using a
single adjustable LC tuned circuit as a pre-selector in conjunction
with a length of wire and a ground connection of some sort. But it
might have an adverse effect.

My guess is that you will end up with a new, Japanese, very expensive,
battery-operated, communications-grade receiver at the end of a
100-feet length of 18-gauge magnet wire. Even if the wire is just
strewn on the ground.

Wait a bit and Chinese, equally good, 1/2-price versions may become
available.

Economics provide the foundations of all engineering. If you don't
understand economics then you don't understand anything. Not even SWR
or the portion of a dipole from which most of the radiation is
supposed to occur.
----
Regards, Reg.

Aye Reg--economics rules the world... except my very own bench... and then it is my wallet and "tight a$$ nature"... I am little better than those buggers who want to keep all the money for themselves! grin

And, you are right again, I have been reduced to the humble L-tuner in the past... and it does work ok...

For the radio gnd, in the past, I used a modified plug into the "record" jack which is available, and use its gnd connection(from the gnd on that plug--which "seems" to actually be hooked to circuit board ground, special screws hold the back on the radio which I do not have a tool to remove (similar to an "allen wrench"--but different)--and never looked hard for one--or machined one,for the L-Tuner, however, a modest gain in performance seems to be realized by using a real earth ground, even to the point of being able to pull the radio ground while still realizing the benefit, and a modest adjustment of the L-tuner--I expect EXTREME impedance at the whip--even touching the whip degrades signal reception drastically--when other ant is hooked....

I simply measured the gnd I get from the "ground plug" I am using to the neg of the batteries, they are at the same level, and I decided to call that close enough to call gnd...

Warmest regards,
John
"Reg Edwards" wrote in message ...
Sorry to disappoint you John.

Nobody has ever made a significant improvement using aligator clips,
lengths of wire and baluns on a portable whip receiver. Except, if
lucky, merely by chance on one band at the expense of the others.

You may, however, hear a bunch of claims, e.g., by CB-ers and
plagiarising old-wives, based on imagination and wishful thinking.

Signal to noise ratio is what matters. And that's an uncontrollable
function of the incoming signals and noise. the ionosphere, and of the
receiver itself.

However, it's quite interesting to experiment with longer antennas.
Obtain a circuit diagram of the receiver and try to predict what will
happen - if anything.

A most elementary circuit analysis is all that's needed. Otherwise you
will be working entirely in the dark.

Clear your head and forget about a balun. You must have been reading
the wrong magazines articles. You are dealing with an
unbalanced-to-unbalanced, very high impedance-to-high impedance
situation.

Consider a ground conection to the receiver chassis. This lowers the
impedance to more predictable values. OK if you are located
conveniently near to a domestic plumbing system. But even a short rod
in good soil will have some effect for either better or worse.

If you insist, signal to noise ratio MIGHT be improved by using a
single adjustable LC tuned circuit as a pre-selector in conjunction
with a length of wire and a ground connection of some sort. But it
might have an adverse effect.

My guess is that you will end up with a new, Japanese, very expensive,
battery-operated, communications-grade receiver at the end of a
100-feet length of 18-gauge magnet wire. Even if the wire is just
strewn on the ground.

Wait a bit and Chinese, equally good, 1/2-price versions may become
available.

Economics provide the foundations of all engineering. If you don't
understand economics then you don't understand anything. Not even SWR
or the portion of a dipole from which most of the radiation is
supposed to occur.
----
Regards, Reg.

.... when other ant is hooked...
--should have been--
....when NO other ant is hooked...

John
"John Smith" wrote in message ...
Aye Reg--economics rules the world... except my very own bench... and then it is my wallet and "tight a$$ nature"... I am little better than those buggers who want to keep all the money for themselves! grin

And, you are right again, I have been reduced to the humble L-tuner in the past... and it does work ok...

For the radio gnd, in the past, I used a modified plug into the "record" jack which is available, and use its gnd connection(from the gnd on that plug--which "seems" to actually be hooked to circuit board ground, special screws hold the back on the radio which I do not have a tool to remove (similar to an "allen wrench"--but different)--and never looked hard for one--or machined one,for the L-Tuner, however, a modest gain in performance seems to be realized by using a real earth ground, even to the point of being able to pull the radio ground while still realizing the benefit, and a modest adjustment of the L-tuner--I expect EXTREME impedance at the whip--even touching the whip degrades signal reception drastically--when other ant is hooked....

I simply measured the gnd I get from the "ground plug" I am using to the neg of the batteries, they are at the same level, and I decided to call that close enough to call gnd...

Warmest regards,
John
"Reg Edwards" wrote in message ...
Sorry to disappoint you John.

Nobody has ever made a significant improvement using aligator clips,
lengths of wire and baluns on a portable whip receiver. Except, if
lucky, merely by chance on one band at the expense of the others.

You may, however, hear a bunch of claims, e.g., by CB-ers and
plagiarising old-wives, based on imagination and wishful thinking.

Signal to noise ratio is what matters. And that's an uncontrollable
function of the incoming signals and noise. the ionosphere, and of the
receiver itself.

However, it's quite interesting to experiment with longer antennas.
Obtain a circuit diagram of the receiver and try to predict what will
happen - if anything.

A most elementary circuit analysis is all that's needed. Otherwise you
will be working entirely in the dark.

Clear your head and forget about a balun. You must have been reading
the wrong magazines articles. You are dealing with an
unbalanced-to-unbalanced, very high impedance-to-high impedance
situation.

Consider a ground conection to the receiver chassis. This lowers the
impedance to more predictable values. OK if you are located
conveniently near to a domestic plumbing system. But even a short rod
in good soil will have some effect for either better or worse.

If you insist, signal to noise ratio MIGHT be improved by using a
single adjustable LC tuned circuit as a pre-selector in conjunction
with a length of wire and a ground connection of some sort. But it
might have an adverse effect.

My guess is that you will end up with a new, Japanese, very expensive,
battery-operated, communications-grade receiver at the end of a
100-feet length of 18-gauge magnet wire. Even if the wire is just
strewn on the ground.

Wait a bit and Chinese, equally good, 1/2-price versions may become
available.

Economics provide the foundations of all engineering. If you don't
understand economics then you don't understand anything. Not even SWR
or the portion of a dipole from which most of the radiation is
supposed to occur.
----
Regards, Reg.

JS,

Without a ground connected to a battery-operated portable receiver,
for example via the earphone socket, the input impedance at the
antenna socket is umpteen thousand ohms.

So it doesn't matter very much what you do about the whip.

But you knew that before you asked the question. So why ask it? ;o)

I would guess, in your younger days, you were a gifted, over-active
little boy who asked questions with a motive always different from the
obvious one.

It is indeed a very useful technique for gaining information about
which the subject may be reluctant to divulge. Perhaps you should have
been employed as a WMD inspector to discover that none existed years
before Saddam confessed that he never had any and had never possessed
the facilities to manufacture them.

But it's a dangerous occupation. The senior British WMD Inspector
committed suicide shortly after blowing the whistle - or so the story
goes. ;o) ;o) ;o) ;o)

Whilst on the subject of whip antennas you may be interested to run
program WHIP_1 which analyses performance, from transmitter to
receiver input, of a typical vehicle-mounted whip + un-un transformer
+ coax line + receiver.
----
.................................................. ..........
Regards from Reg, G4FGQ
For Free Radio Design Software go to
http://www.btinternet.com/~g4fgq.regp
.................................................. ..........

JS,