Probably a stupid question...
 

Is there a fairly quick answer to the question of what is involved with
matching an RF amplifier to a whip antenna? I have built an active, tunable
antenna to assist my shortwave receiver, and it works wonderfully on the
110' random-wire antenna up on the roof, but only picks up the strong
stations with the whip. Those that it picks up come in great, but there are
others that it is able to detect but not lock on to and make intelligable,
IE BBC Africa, 7160 kHz around 0400/0500 UTC (and I am on the Gulf Coast of
Texas).

Just wondering,

Thanks for any feedback or input.

Dave

Probably a stupid question...
 

On Sat, 10 Nov 2007 01:04:00 -0600, "Dave" wrote:

Is there a fairly quick answer to the question of what is involved with
matching an RF amplifier to a whip antenna? I have built an active, tunable
antenna to assist my shortwave receiver, and it works wonderfully on the
110' random-wire antenna up on the roof, but only picks up the strong
stations with the whip. Those that it picks up come in great, but there are
others that it is able to detect but not lock on to and make intelligable,
IE BBC Africa, 7160 kHz around 0400/0500 UTC (and I am on the Gulf Coast of
Texas).

Just wondering,

Thanks for any feedback or input.

Dave


is the whip some sort of reduced size antenna?

The smaller an antenna is, the worse is the performance.

w.

Probably a stupid question...
 

"Helmut Wabnig" hwabnig@ .- --- -. DOT .- t wrote in message
...
On Sat, 10 Nov 2007 01:04:00 -0600, "Dave" wrote:

Is there a fairly quick answer to the question of what is involved with
matching an RF amplifier to a whip antenna? I have built an active,
tunable
antenna to assist my shortwave receiver, and it works wonderfully on the
110' random-wire antenna up on the roof, but only picks up the strong
stations with the whip. Those that it picks up come in great, but there
are
others that it is able to detect but not lock on to and make intelligable,
IE BBC Africa, 7160 kHz around 0400/0500 UTC (and I am on the Gulf Coast
of
Texas).

Just wondering,

Thanks for any feedback or input.

Dave


is the whip some sort of reduced size antenna?

The smaller an antenna is, the worse is the performance.

w.

It's a 43 inch collapsable antenna (7 segments.) Maybe I just need more
amplification...

Thanks,

Dave

Probably a stupid question...
 

On Sat, 10 Nov 2007 01:58:28 -0600, Dave wrote:
"Helmut Wabnig" hwabnig@ .- --- -. DOT .- t wrote:
On Sat, 10 Nov 2007 01:04:00 -0600, "Dave" wrote:

Is there a fairly quick answer to the question of what is involved with
matching an RF amplifier to a whip antenna? I have built an active, tunable
antenna to assist my shortwave receiver, and it works wonderfully on the
110' random-wire antenna up on the roof, but only picks up the strong
stations with the whip. Those that it picks up come in great, but there are
others that it is able to detect but not lock on to and make intelligable,
IE BBC Africa, 7160 kHz around 0400/0500 UTC (and I am on the Gulf Coast
of Texas).

is the whip some sort of reduced size antenna?

The smaller an antenna is, the worse is the performance.

It's a 43 inch collapsable antenna (7 segments.) Maybe I just need more
amplification...

No. You need more antenna.

If you add amplification to a marginally performing antenna, you will
also amplify all the nearby interference: power line noise, dimmer
lights, electrical motors, poorly shielded TVs, etc. usw.

Sure, the desired signal(s) may come up in strength by adding more
amplification to a poor antenna, but everything you _don't_ want to hear
will be stronger, too.

Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
38.24N 104.55W | @ config.com | Jonesy | OS/2
*** Killfiling google posts: http://jonz.net/ng.htm

Probably a stupid question...
 

On Sat, 10 Nov 2007 01:58:28 -0600, "Dave" wrote:

It's a 43 inch collapsable antenna (7 segments.) Maybe I just need more
amplification...

Hi Dave,

You need more antenna...
... but not much more.

When I was in Africa with a Radio Shack $40 SW receiver, the whip was
a dummy load that let me hear the internal microprocessor clock that
was driving the digital display. I attached 20 feet of wire-wrap wire
to the whip, threw the wire end (weighted with a Rand) up onto the
reed roof of the lodge I was in and I got more signals than I could
handle with only about 4 meters of height. The bands from 2.3 MHz to
16 MHz played all day/night long.

73's
Richard Clark, KB7QHC

Probably a stupid question...
 

Dave wrote:
It's a 43 inch collapsable antenna (7 segments.) Maybe I just need more
amplification...

For maximum power transfer from the antenna to the
receiving load, you need a matching network, i.e.
a low-loss antenna tuner. What is the dynamic gain
range of the receiving load device?
--
73, Cecil http://www.w5dxp.com

Probably a stupid question...
 

Hello Cecil,

Thank you for the interest, and the question. Last time I had the RF
amplier on the scope and sig generator, it was giving me approximately 100
mV output with something that *looked* like a millivolt or two input
(possibly at much as 5 mV but no more), at 5 and again at 10 MHz. Now, I am
enough of an RF newbie that I *think* this is what you are asking, but if
not then please enlighten me. I think I understand the need for a low-loss
antenna tuner, which I am trying to improvise with a 25 ohm wire-wound pot
acting as an autotransformer, ala The Miracle Whip (QST, July 2001 PP
32-35.) And it seems to be working to some extent, just not in the ideal
way I need. I am able to pick up Radio Nederlands on 6145 kHz (I *think*
that's the frequency) off of the whip, but not BBC Africa on 7160 kHz, even
if the radio stops there and seems to realize that there is something going
on, but just can't pull it out of the mud. I am able to pull in BBC Africa
on 7160 kHz with the external 110' random-wire antenna, and that with a bare
minumun of noise. The whip however, just gives me the noise. I am about to
do some more experimenting with different WW pots to see if I can get
anything better. If all of this sounds totally bat-****, please forgive.
It does seem to work at least half as good as I need however, and I am
hoping to tease out the rest.

Please let me know if I am headed up the wrong creek with my answers. Hate
to say it, but am honestly making this up as I go along (obviously).

Thanks again,

Dave

"Cecil Moore" wrote in message
...
Dave wrote:
It's a 43 inch collapsable antenna (7 segments.) Maybe I just need more
amplification...

For maximum power transfer from the antenna to the
receiving load, you need a matching network, i.e.
a low-loss antenna tuner. What is the dynamic gain
range of the receiving load device?
--
73, Cecil http://www.w5dxp.com

Probably a stupid question...
 

Update: replaced the 25 ohm WW pot with a 1 ohm 4 watt WW potentiometer,
with surprisingly good results. Am now able to pull in BBC Africa on 7160
kHz, although there is a somewhat faint high-pitch whine behind it. Still,
it is definetly intelligable. At least 1000% better than it was. When
attached to the external antenna, it is downright incredible. The only
thing I have trouble picking up with the whip is WWV at 5 MHz (and 2.5 MHz
is out of the question). With the external antenna however, these come
through like gangbusters. The acid test will come at 1300 UTC when I try
to pick up Voice of Korea. If I can pull that out of the noise, I will be
ecstatic. That is what I have been working towards since I started this
project. Oh, and it helps if all your wires are connected, and the one
carrying the RF to the input of the first amplifier stage is not hanging
loose, near it's intended connectionpoint, due to a broken solder joint.
Found that while installing the 1 ohm pot and had to go back and see how the
25 ohm pot performed once the wire was reconnected. Better, but still not
ideal by any means. Then installed the 1 ohm pot, and got surprised. If
you want to see the schematic, I can post it to
alt.binaries.schematics.electronic.

Hoping to hear from you again on how to improve reception further.

Thanks,

Dave

"Dave" wrote in message
...
Hello Cecil,

Thank you for the interest, and the question. Last time I had the RF
amplier on the scope and sig generator, it was giving me approximately 100
mV output with something that *looked* like a millivolt or two input
(possibly at much as 5 mV but no more), at 5 and again at 10 MHz. Now, I
am enough of an RF newbie that I *think* this is what you are asking, but
if not then please enlighten me. I think I understand the need for a
low-loss antenna tuner, which I am trying to improvise with a 25 ohm
wire-wound pot acting as an autotransformer, ala The Miracle Whip (QST,
July 2001 PP 32-35.) And it seems to be working to some extent, just not
in the ideal way I need. I am able to pick up Radio Nederlands on 6145
kHz (I *think* that's the frequency) off of the whip, but not BBC Africa
on 7160 kHz, even if the radio stops there and seems to realize that there
is something going on, but just can't pull it out of the mud. I am able
to pull in BBC Africa on 7160 kHz with the external 110' random-wire
antenna, and that with a bare minumun of noise. The whip however, just
gives me the noise. I am about to do some more experimenting with
different WW pots to see if I can get anything better. If all of this
sounds totally bat-****, please forgive. It does seem to work at least
half as good as I need however, and I am hoping to tease out the rest.

Please let me know if I am headed up the wrong creek with my answers.
Hate to say it, but am honestly making this up as I go along (obviously).

Thanks again,

Dave

"Cecil Moore" wrote in message
...
Dave wrote:
It's a 43 inch collapsable antenna (7 segments.) Maybe I just need more
amplification...

For maximum power transfer from the antenna to the
receiving load, you need a matching network, i.e.
a low-loss antenna tuner. What is the dynamic gain
range of the receiving load device?
--
73, Cecil http://www.w5dxp.com

Probably a stupid question...
 

Dave,
In a nut-shell, a larger antenna will tend to be more 'receptive'
at lower frequencies. Then you can think about matching the
impedances of the antenna system and receiver.
Larger antennas have the 'problem' of being 'larger', as in where
do you put the thing? Reducing the size of an antenna can be more
practical mechanically, but tends to be less practical electrically
(noise, less 'receptive', etc, etc.). Your 'best' bet would be to
find a reasonable compromise between the two kinds of 'practical'
thingys (mechanical/electrical). Usually easier if you can make it
bigger, sort of.
- 'Doc

(all puns intended, even the ones I didn't intend)

Probably a stupid question...
 

Hey Doc,

Thanks for the input. I overslept for the 1300 UTC broadcast of VOK, but
did pick up the 1500 broadcast. Unfortunately the RF amp offers nothing
over the whip that comes with (and already attached to) my Sony 7600GR
portable. More work to be done. Need to tease out the secrets of impedance
matching, as well as add a boatload of additonal amplification. Damn it's
hard to compete with a successful commercial product. Still, I have at
least reached the level of performance with the RF amp that the preamp in my
7600GR already offered, with the exception of a little additional background
noise.

Hope I didn't discourage Cecil from trying to help. Sorry if I did. I
don't mean to be ignorant, and it is something I am trying to change.

73 and good DX

Dave

wrote in message
ups.com...
Dave,
In a nut-shell, a larger antenna will tend to be more 'receptive'
at lower frequencies. Then you can think about matching the
impedances of the antenna system and receiver.
Larger antennas have the 'problem' of being 'larger', as in where
do you put the thing? Reducing the size of an antenna can be more
practical mechanically, but tends to be less practical electrically
(noise, less 'receptive', etc, etc.). Your 'best' bet would be to
find a reasonable compromise between the two kinds of 'practical'
thingys (mechanical/electrical). Usually easier if you can make it
bigger, sort of.
- 'Doc

(all puns intended, even the ones I didn't intend)

Probably a stupid question...
 

"Dave" wrote in message
...
Hey Doc,

Thanks for the input. I overslept for the 1300 UTC broadcast of VOK, but
did pick up the 1500 broadcast. Unfortunately the RF amp offers nothing
over the whip that comes with (and already attached to) my Sony 7600GR
portable. More work to be done. Need to tease out the secrets of
impedance matching, as well as add a boatload of additonal amplification.
Damn it's

No mater how much amplification you have, if the antenna is not big enough
or the proprgation is not good you will not pick up a station. There is a
limit as to how much you can amplify a signal before the noise floor takes
over. For signals below 15 to 30 mhz or so the noise floor is very high so
not too much amplification can be used to help with the reception.

Probably a stupid question...
 

"Ralph Mowery" wrote in message
...

"Dave" wrote in message
...
Hey Doc,

Thanks for the input. I overslept for the 1300 UTC broadcast of VOK, but
did pick up the 1500 broadcast. Unfortunately the RF amp offers nothing
over the whip that comes with (and already attached to) my Sony 7600GR
portable. More work to be done. Need to tease out the secrets of
impedance matching, as well as add a boatload of additonal amplification.
Damn it's

No mater how much amplification you have, if the antenna is not big enough
or the proprgation is not good you will not pick up a station. There is a
limit as to how much you can amplify a signal before the noise floor takes
over. For signals below 15 to 30 mhz or so the noise floor is very high
so not too much amplification can be used to help with the reception.



Hey Ralph, thanks for coming in. I am wondering though if I can't tune out
some of the noise,and eliminate more with a directional antenna (which I
currently don't have.) Would an IF stage not help me here? Or a second
tuning function, on the output? Just wondering.

Do appreciate your comments. If I'm wrong I'm wrong, I was just thinking
these things might help. No? The signal I am trying to clean up is at 9335
kHz.

Dave

Probably a stupid question...
 

Dave,
Would another 'IF' stage, or filtering, or 'nulling', or whatever you
want to call it, help? Sure. But then you start running into the
'practical' thingy again. It can get sort of complicated deciding
what is 'noise' and what is desired signal. DSP does a lot of that
when told how to do it by the controlling algorithms (or is that 'Al-
Gore-isms'? sorry, I know better, just can't help it). The mainest
problem is the time it takes to do that, it is not instantaneous. And
if you are going to make that controlling algorithm variable, the time
it takes makes things even more time consuming, not to mention
difficult. Keeping in mind that simply making the antenna larger/
longer can do about the same thing at less expense (time/work/$$$),
why not? Easy to do with a recording (sort of), very difficult in
real time. Manually doing all that is almost impossible. How do you
decide what to 'do' before it's too late? There are limits with
today's technology. So, put it off till 'tomorrow', right?
- 'Doc

(all puns intended, even the ones I didn't intend)

Probably a stupid question...
 

Hmmm. Yeah. sigh Point taken. I guess this is just my hobby, and I
really don't have anything better to do (other than housework.) I don't
know what to say. Guess I just have to prove to myself that everything that
can be done has been done, or that it's not worth the effort for the
outcome. sigh again.

I do appreciate all of the feedback, and the patience with my ignorance. I
am trying to make this thing work off of a whip for portability's sake, and
am just not willing to accept defeat yet. May not be much longer though...
It does work great on the external antenna, I just want it to work better
off of the whip.

Thank you, all of you who replied. And thank you, doc, for the final simple
analysis. I don't mean to be stubborn, I just have to try everything to
prove to myself that it is as good as it can be. Sorry. Guess I am
stubborn after all.

The hand-holding is appreciated. Sorry if I frustrated you guys. Thanks
again for your patience.

Dave

wrote in message
oups.com...
Dave,
Would another 'IF' stage, or filtering, or 'nulling', or whatever you
want to call it, help? Sure. But then you start running into the
'practical' thingy again. It can get sort of complicated deciding
what is 'noise' and what is desired signal. DSP does a lot of that
when told how to do it by the controlling algorithms (or is that 'Al-
Gore-isms'? sorry, I know better, just can't help it). The mainest
problem is the time it takes to do that, it is not instantaneous. And
if you are going to make that controlling algorithm variable, the time
it takes makes things even more time consuming, not to mention
difficult. Keeping in mind that simply making the antenna larger/
longer can do about the same thing at less expense (time/work/$$$),
why not? Easy to do with a recording (sort of), very difficult in
real time. Manually doing all that is almost impossible. How do you
decide what to 'do' before it's too late? There are limits with
today's technology. So, put it off till 'tomorrow', right?
- 'Doc

(all puns intended, even the ones I didn't intend)

Probably a stupid question...
 

Dave wrote:
I do appreciate all of the feedback, and the patience with my ignorance.

Have you considered a screwdriver antenna? Many hams
try a whip with an autotuner, are dissatisfied, and
wind up with a screwdriver antenna for a 12 dB
improvement, at least on 3.8 MHz.
--
73, Cecil http://www.w5dxp.com

Probably a stupid question...
 

Cecil Moore wrote:
Dave wrote:
I do appreciate all of the feedback, and the patience with my ignorance.

Have you considered a screwdriver antenna? Many hams
try a whip with an autotuner, are dissatisfied, and
wind up with a screwdriver antenna for a 12 dB
improvement, at least on 3.8 MHz.


-----------


(Spoken in Columbo's voice and mannerisms)"Uh, podden me, Cec, butta,
12db improvement compared to what?"

A 108" whip tuned with an electronic autotuner at the base, on the
trailer hitch attached to an average car should be just as (was gonna
use the words efficient and effective - but thought better of it) as a
short little whip mounted in PVC pipe at the same location, but using a
mechanical tuner (screwdriver) instead of an electronic autotuner such
as an AH-4.

Yes, I have considered a screwdriver antenna, just don't know where to
put it on my minivan(s).

As you can tell, I'm coming in late on this one. Thanks for your patience.


Ed, NM2K

Probably a stupid question...
 

On Mon, 12 Nov 2007 10:51:58 -0500, Ed Cregger
wrote:

A 108" whip tuned with an electronic autotuner at the base, on the
trailer hitch attached to an average car should be just as (was gonna
use the words efficient and effective - but thought better of it) as a
short little whip mounted in PVC pipe at the same location, but using a
mechanical tuner (screwdriver) instead of an electronic autotuner such
as an AH-4.

Hi Ed,

This is a bit garbled, but the sense is there.

You are comparing a bad installation to a bad installation - yes one
will be as efficient/effective as the other.

The tuner at the base of the whip has invested resonance in the wrong
place. A coil at the base of a whip also invests resonance in the
wrong place. A coil higher in the whip invests resonance in the
better places by degree.

Ostensibly, the premium degree of coil placement is one half to two
thirds the way up the whip. A screwdriver antenna attempts to make
this resonance investment. If you will note, the coil section falls
between a lower tube and an upper whip.

There is a world of discussion as to why it is better that I will
leave to others to fill in.

73's
Richard Clark, KB7QHC

Probably a stupid question...
 

Ed Cregger wrote:
Cecil Moore wrote:
Have you considered a screwdriver antenna? Many hams
try a whip with an autotuner, are dissatisfied, and
wind up with a screwdriver antenna for a 12 dB
improvement, at least on 3.8 MHz.

(Spoken in Columbo's voice and mannerisms)"Uh, podden me, Cec, butta,
12db improvement compared to what?"

Compared to the aforementioned "whip with an autotuner".
--
73, Cecil http://www.w5dxp.com

Probably a stupid question...
 

"Dave" wrote in message
...

Hey Ralph, thanks for coming in. I am wondering though if I can't tune
out some of the noise,and eliminate more with a directional antenna (which
I currently don't have.) Would an IF stage not help me here? Or a second
tuning function, on the output? Just wondering.

Do appreciate your comments. If I'm wrong I'm wrong, I was just thinking
these things might help. No? The signal I am trying to clean up is at
9335 kHz.


Dave you started with a simple whip 40 some inches long. As I mentioned ,
no mater how much amplification you have , the local and not so local noise
will limit the ammount of amplification you can use. All you will amplify
is noise. Lets say you have a noise floor of .3 microvolts and a signal is
picked up from the antenna of .4 microvolts. Your signal will be higher
than the noise and you can hear it to some extent. If the noise is .5
microvolts and you get the same signal , then you will not hear the signal.
If you add an amplifier (one that has no noise of its own , which is
impossiable bu the way) you may get .8 uv of signal, but you will then have
1.0 uv of noise and you will still not hear the signal. The amp may add .1
uv of noise so you then get 1.1 uv of noise and only .8 uv of signal.

You may change the antenna to a tuned loop. Take a couple of sticks about 3
feet long and make an X out of them and wrap a few turns of wire around the
outside of the X so you have a loop about 3 feet square and tune it with a
capacitor to the frequency you wish to hear and it will be somewhat
directional. That may help.

The main thing is that a 3 foot whip in the house is not going to be a very
good antenna for shortwave.

Probably a stupid question...
 

"Ralph Mowery" wrote in message
...

"Dave" wrote in message
...

Hey Ralph, thanks for coming in. I am wondering though if I can't tune
out some of the noise,and eliminate more with a directional antenna
(which I currently don't have.) Would an IF stage not help me here? Or
a second tuning function, on the output? Just wondering.

Do appreciate your comments. If I'm wrong I'm wrong, I was just thinking
these things might help. No? The signal I am trying to clean up is at
9335 kHz.


Dave you started with a simple whip 40 some inches long. As I mentioned ,
no mater how much amplification you have , the local and not so local
noise will limit the ammount of amplification you can use. All you will
amplify is noise. Lets say you have a noise floor of .3 microvolts and a
signal is picked up from the antenna of .4 microvolts. Your signal will
be higher than the noise and you can hear it to some extent. If the noise
is .5 microvolts and you get the same signal , then you will not hear the
signal. If you add an amplifier (one that has no noise of its own , which
is impossiable bu the way) you may get .8 uv of signal, but you will then
have 1.0 uv of noise and you will still not hear the signal. The amp may
add .1 uv of noise so you then get 1.1 uv of noise and only .8 uv of
signal.

You may change the antenna to a tuned loop. Take a couple of sticks about
3 feet long and make an X out of them and wrap a few turns of wire around
the outside of the X so you have a loop about 3 feet square and tune it
with a capacitor to the frequency you wish to hear and it will be somewhat
directional. That may help.

The main thing is that a 3 foot whip in the house is not going to be a
very good antenna for shortwave.



Huuuuhhhh. Okay, I think I am beginning to understand. At least, when you
put it in those terms.

I had thought about using a loop, but for some reason decided to try the
whip first. I guess 'cause that's what I had handy, and I wasn't sure how I
would mount a loop. Until I can figure that out, I am going to try tuning
the output of the RF amplifier the same way I tune the input. If I can work
out the last detail of doing that.

Your words, and numbers, are much appreciated. And your patience.

Thanks, Ralph.

Dave

Probably a stupid question...
 

"Cecil Moore" wrote in message
et...
Dave wrote:
I do appreciate all of the feedback, and the patience with my ignorance.

Have you considered a screwdriver antenna? Many hams
try a whip with an autotuner, are dissatisfied, and
wind up with a screwdriver antenna for a 12 dB
improvement, at least on 3.8 MHz.
--
73, Cecil http://www.w5dxp.com

Hey Cecil,

Not sure what a screwdriver antenna is. Off to Google...

Dave

Probably a stupid question...
 

wrote in message
ups.com...
Dave,
In a nut-shell, a larger antenna will tend to be more 'receptive'
at lower frequencies.

Agree. Years ago I was an avid broadcast band (BCB) DX'er, usually getting
what I wanted late at night. However, when I installed about a 50-foot
dipole wrapped around the inside of my garage, I found an exciting number of
distant stations available during the day. It seems old hat today, but the
experience was valid, I think.

Probably a stupid question...
 

"Sal M. Onella" wrote in message
...

wrote in message
ups.com...
Dave,
In a nut-shell, a larger antenna will tend to be more 'receptive'
at lower frequencies.

Agree. Years ago I was an avid broadcast band (BCB) DX'er, usually
getting
what I wanted late at night. However, when I installed about a 50-foot
dipole wrapped around the inside of my garage, I found an exciting number
of
distant stations available during the day. It seems old hat today, but
the
experience was valid, I think.



Oh, I understand that a larger antenna is much more receptive. And I have a
110' random wire that does wonders. I am just wanting some sort of
reception booster to take with me if we have to bug out for a hurricane
again. That, and the challange interests me.

Dave

Probably a stupid question...
 

On Tue, 13 Nov 2007 07:31:14 -0600, "Dave" wrote:

I am just wanting some sort of
reception booster to take with me if we have to bug out for a hurricane
again.

Hi Dave,

Was my successful experience of adding 4 meters of wire height too
simple? Didn't it cost enough? Was it too low tech?

That, and the challange interests me.

It would seem the bar is especially low as it is - that or this
appeals to some notion of having a wrist SW radio a la Dick Tracy.

There have been lots of special challenges posted here in the past
that outperform. One might be instructive that several regulars here
might remember: Pound a nail into a tree and connect your whip
antenna to that. Reports would suggest DX opportunities abound.

73's
Richard Clark, KB7QHC

Probably a stupid question...
 

Richard Clark wrote:

There have been lots of special challenges posted here in the past
that outperform. One might be instructive that several regulars here
might remember: Pound a nail into a tree and connect your whip
antenna to that. Reports would suggest DX opportunities abound.

I just knew you wood say that.


- 73 de Mike N3LI -

Probably a stupid question...
 

"Dave" wrote in message
...

"Ralph Mowery" wrote in message
...

"Dave" wrote in message
...

Hey Ralph, thanks for coming in. I am wondering though if I can't tune
out some of the noise,and eliminate more with a directional antenna
(which I currently don't have.) Would an IF stage not help me here? Or
a second tuning function, on the output? Just wondering.

Do appreciate your comments. If I'm wrong I'm wrong, I was just
thinking these things might help. No? The signal I am trying to clean
up is at 9335 kHz.


Dave you started with a simple whip 40 some inches long. As I mentioned
, no mater how much amplification you have , the local and not so local
noise will limit the ammount of amplification you can use. All you will
amplify is noise. Lets say you have a noise floor of .3 microvolts and a
signal is picked up from the antenna of .4 microvolts. Your signal will
be higher than the noise and you can hear it to some extent. If the
noise is .5 microvolts and you get the same signal , then you will not
hear the signal. If you add an amplifier (one that has no noise of its
own , which is impossiable bu the way) you may get .8 uv of signal, but
you will then have 1.0 uv of noise and you will still not hear the
signal. The amp may add .1 uv of noise so you then get 1.1 uv of noise
and only .8 uv of signal.

You may change the antenna to a tuned loop. Take a couple of sticks
about 3 feet long and make an X out of them and wrap a few turns of wire
around the outside of the X so you have a loop about 3 feet square and
tune it with a capacitor to the frequency you wish to hear and it will be
somewhat directional. That may help.

The main thing is that a 3 foot whip in the house is not going to be a
very good antenna for shortwave.



Huuuuhhhh. Okay, I think I am beginning to understand. At least, when you
put it in those terms.

I had thought about using a loop, but for some reason decided to try the
whip first. I guess 'cause that's what I had handy, and I wasn't sure how
I would mount a loop. Until I can figure that out, I am going to try
tuning the output of the RF amplifier the same way I tune the input. If I
can work out the last detail of doing that.

Your words, and numbers, are much appreciated. And your patience.

Thanks, Ralph.

Dave



Okay, tuning the output along with the input does help, but it's still very
close to what the built in whip on the 7600GR does. The only real
difference between now and before is less noise, which makes the
intelligence more accessible (easier to understand what they're saying.)
Time to try the loop, for directional input. I still wonder if something I
thought about a while back might work, which is to mount a second whip on
the other side of the case and seperate them with coax internally. I had
some numbers in mind at one time, but have forgotten them. Roy Lewellan
suggested I try EZNec, but I haven't been able to dedicate as much time to
it as I thought I would. And someone I met is mailing me a copy of the CD
from the latest ARRL Antenna Handbook. It is my understanding that phased
verticles have been completely re-addressed in this latest copy, which
interests me. For some reason books, even on the computer, speak to me more
easily than applications for modeling given situations. Going to go try
EZNec again.

One thing I realized, to my own benefit. The house has steel siding, and
that degrades the performance of the 'whipped' RF amplifier considerably.
Outside, in the driveway, it works as well as it does inside, off of the
external 110' random wire. Which is a better performance by at least a
factor of 10 when compared to inside, off of the whip. I'm going to keep
squeezing this lemon. One way or another. It keeps improving by
considerable steps, I just have to work the bugs out.

Thanks all, for ideas and feedback. And patience.

Dave

Probably a stupid question...
 

"Dave" wrote in message
...

"Dave" wrote in message
...

"Ralph Mowery" wrote in message
...

"Dave" wrote in message
...

Hey Ralph, thanks for coming in. I am wondering though if I can't tune
out some of the noise,and eliminate more with a directional antenna
(which I currently don't have.) Would an IF stage not help me here?
Or a second tuning function, on the output? Just wondering.

Do appreciate your comments. If I'm wrong I'm wrong, I was just
thinking these things might help. No? The signal I am trying to clean
up is at 9335 kHz.


Dave you started with a simple whip 40 some inches long. As I mentioned
, no mater how much amplification you have , the local and not so local
noise will limit the ammount of amplification you can use. All you will
amplify is noise. Lets say you have a noise floor of .3 microvolts and
a signal is picked up from the antenna of .4 microvolts. Your signal
will be higher than the noise and you can hear it to some extent. If
the noise is .5 microvolts and you get the same signal , then you will
not hear the signal. If you add an amplifier (one that has no noise of
its own , which is impossiable bu the way) you may get .8 uv of signal,
but you will then have 1.0 uv of noise and you will still not hear the
signal. The amp may add .1 uv of noise so you then get 1.1 uv of noise
and only .8 uv of signal.

You may change the antenna to a tuned loop. Take a couple of sticks
about 3 feet long and make an X out of them and wrap a few turns of wire
around the outside of the X so you have a loop about 3 feet square and
tune it with a capacitor to the frequency you wish to hear and it will
be somewhat directional. That may help.

The main thing is that a 3 foot whip in the house is not going to be a
very good antenna for shortwave.



Huuuuhhhh. Okay, I think I am beginning to understand. At least, when
you put it in those terms.

I had thought about using a loop, but for some reason decided to try the
whip first. I guess 'cause that's what I had handy, and I wasn't sure
how I would mount a loop. Until I can figure that out, I am going to
try tuning the output of the RF amplifier the same way I tune the input.
If I can work out the last detail of doing that.

Your words, and numbers, are much appreciated. And your patience.

Thanks, Ralph.

Dave



Okay, tuning the output along with the input does help, but it's still
very close to what the built in whip on the 7600GR does. The only real
difference between now and before is less noise, which makes the
intelligence more accessible (easier to understand what they're saying.)
Time to try the loop, for directional input. I still wonder if something
I thought about a while back might work, which is to mount a second whip
on the other side of the case and seperate them with coax internally. I
had some numbers in mind at one time, but have forgotten them. Roy
Lewellan suggested I try EZNec, but I haven't been able to dedicate as
much time to it as I thought I would. And someone I met is mailing me a
copy of the CD from the latest ARRL Antenna Handbook. It is my
understanding that phased verticles have been completely re-addressed in
this latest copy, which interests me. For some reason books, even on the
computer, speak to me more easily than applications for modeling given
situations. Going to go try EZNec again.

One thing I realized, to my own benefit. The house has steel siding, and
that degrades the performance of the 'whipped' RF amplifier considerably.
Outside, in the driveway, it works as well as it does inside, off of the
external 110' random wire. Which is a better performance by at least a
factor of 10 when compared to inside, off of the whip. I'm going to keep
squeezing this lemon. One way or another. It keeps improving by
considerable steps, I just have to work the bugs out.

Thanks all, for ideas and feedback. And patience.

Dave



Crap. Just read my own post and realized I misspelled Roy Lewallen's last
name. My apologies. It's not been a good day...

Dave

Probably a stupid question...
 

Dave wrote:

Crap. Just read my own post and realized I misspelled Roy Lewallen's last
name. My apologies. It's not been a good day...

Don't feel bad. My sister-in-law still spells it like you did, and I've
been married to her sister for 39 years. Many years ago, I idly
collected misspellings from mail, memos, and the like, and had
accumulated more than 30 different ones when I lost interest.

One way is just as good as another, anyway. My particular spelling came
from the first literate person in my branch of the family who, in about
1850, spelled it like it sounded to him. His brother, and many other
relatives as they each became literate, spelled it in various other
ways. Including, I'm sure, the way you did. Considering the family's
history, it wouldn't surprise me if there are still a few branches yet
to become literate and devise their own spellings.

Roy Lewallen, W7EL

Probably a stupid question...
 

On 13 Nov, 18:10, Roy Lewallen wrote:
Dave wrote:

Crap. Just read my own post and realized I misspelled Roy Lewallen's last
name. My apologies. It's not been a good day...

Don't feel bad. My sister-in-law still spells it like you did, and I've
been married to her sister for 39 years. Many years ago, I idly
collected misspellings from mail, memos, and the like, and had
accumulated more than 30 different ones when I lost interest.

One way is just as good as another, anyway. My particular spelling came
from the first literate person in my branch of the family who, in about
1850, spelled it like it sounded to him. His brother, and many other
relatives as they each became literate, spelled it in various other
ways. Including, I'm sure, the way you did. Considering the family's
history, it wouldn't surprise me if there are still a few branches yet
to become literate and devise their own spellings.

Roy Lewallen, W7EL

Roy's surname is of Welsh origin. Queen Bodacia and her sisters
prevented
Romans who had conquered England in the BC era from conquering Wales.
There is a statue of that defiant queen on the side of the River
Thames
opposite the House of Commons and the House of Lords( and Big Ben).
Roy does not spell his name as in the traditional Welsh language.
Probably those on Ellis Island misspelled it not understanding the
lilting
accent of a Welsh miner.
Art

Probably a stupid question...
 

"art" wrote in message
oups.com...
On 13 Nov, 18:10, Roy Lewallen wrote:
Dave wrote:

Crap. Just read my own post and realized I misspelled Roy Lewallen's
last
name. My apologies. It's not been a good day...

Don't feel bad. My sister-in-law still spells it like you did, and I've
been married to her sister for 39 years. Many years ago, I idly
collected misspellings from mail, memos, and the like, and had
accumulated more than 30 different ones when I lost interest.

One way is just as good as another, anyway. My particular spelling came
from the first literate person in my branch of the family who, in about
1850, spelled it like it sounded to him. His brother, and many other
relatives as they each became literate, spelled it in various other
ways. Including, I'm sure, the way you did. Considering the family's
history, it wouldn't surprise me if there are still a few branches yet
to become literate and devise their own spellings.

Roy Lewallen, W7EL

Roy's surname is of Welsh origin. Queen Bodacia and her sisters
prevented
Romans who had conquered England in the BC era from conquering Wales.
There is a statue of that defiant queen on the side of the River
Thames
opposite the House of Commons and the House of Lords( and Big Ben).
Roy does not spell his name as in the traditional Welsh language.
Probably those on Ellis Island misspelled it not understanding the
lilting
accent of a Welsh miner.
Art


LOL. Sounds like my own family history, with the great grandfather paying
to change the spelling of the last name to correct it, and actually screwing
it up. He couldn't read either, but somehow he got the idea that it was
wrong, and went to the legal trouble of "straightening it out." Yeah,
right. :)

Thanks, I needed that this morning.

Dave

Probably a stupid question...
 

Dave wrote:

Roy Lewallen, W7EL
Roy's surname is of Welsh origin. Queen Bodacia and her sisters
prevented
Romans who had conquered England in the BC era from conquering Wales.
There is a statue of that defiant queen on the side of the River
Thames
opposite the House of Commons and the House of Lords( and Big Ben).
Roy does not spell his name as in the traditional Welsh language.
Probably those on Ellis Island misspelled it not understanding the
lilting
accent of a Welsh miner.
Art


LOL. Sounds like my own family history, with the great grandfather paying
to change the spelling of the last name to correct it, and actually screwing
it up. He couldn't read either, but somehow he got the idea that it was
wrong, and went to the legal trouble of "straightening it out." Yeah,
right. :)

Thanks, I needed that this morning.

My family was in this country long before the Ellis Island immigration
center was established (and before the U.S. was created for that
matter), and the spelling came about as I described, not as Art
speculates. The origin of the name is almost certainly Welsh, and it has
a number of different spellings there, too, among which are Llywelyn,
Llewellyn, and others, probably for the same reason it has so many
different spellings here. The "Ll" is pronounced more like "Cl", but not
with a sound we have in English. But the Welsh pronunciation was surely
gone long before anyone attempted to spell it. I have no idea whether
the original immigrant was a miner as Art speculates, an indentured
servant, or a common criminal.

If I ever get a dog, its name will have to be Gelert.

Roy Lewallen, W7EL

Probably a stupid question...
 

In the early days it was America was where England sent it's criminals
and thiefs where in many places they were absorbed into the
population. When America became independent England then sent its
scoundrels to Australia. America then accepted pretty much all comers
from all countries that were not dominatedby criminal backgrounds ala
Ellis Island When life became difficult in countries such as Ireland
with the potato troubles with the English landlords was difficult and
the mining industy, gold, lead coal etc in Wales petered out because
of cheaper competition America had a need for miners and farmers so
they piled in and spread about the plains of America where the
predominantly English pursued a life of hunting and migrated over the
lower states. It was around this time that the country was flooded by
Germans such that the english language nearly was replaced by German
with the saving grace of immigrants coming from China, the central
European populace, Italians e.t.c chose the english language to learn
because english was dominant in central business areas of the growing
cities.
So the possibility is, that you Roy have a criminal background and
wandered into english hands where they received their just reward by
being removal from the British Isles!
Art

Roy Lewallen wrote:
Dave wrote:

Roy Lewallen, W7EL
Roy's surname is of Welsh origin. Queen Bodacia and her sisters
prevented
Romans who had conquered England in the BC era from conquering Wales.
There is a statue of that defiant queen on the side of the River
Thames
opposite the House of Commons and the House of Lords( and Big Ben).
Roy does not spell his name as in the traditional Welsh language.
Probably those on Ellis Island misspelled it not understanding the
lilting
accent of a Welsh miner.
Art


LOL. Sounds like my own family history, with the great grandfather paying
to change the spelling of the last name to correct it, and actually screwing
it up. He couldn't read either, but somehow he got the idea that it was
wrong, and went to the legal trouble of "straightening it out." Yeah,
right. :)

Thanks, I needed that this morning.

My family was in this country long before the Ellis Island immigration
center was established (and before the U.S. was created for that
matter), and the spelling came about as I described, not as Art
speculates. The origin of the name is almost certainly Welsh, and it has
a number of different spellings there, too, among which are Llywelyn,
Llewellyn, and others, probably for the same reason it has so many
different spellings here. The "Ll" is pronounced more like "Cl", but not
with a sound we have in English. But the Welsh pronunciation was surely
gone long before anyone attempted to spell it. I have no idea whether
the original immigrant was a miner as Art speculates, an indentured
servant, or a common criminal.

If I ever get a dog, its name will have to be Gelert.

Roy Lewallen, W7EL