Transmitting SW antenna question - pls help
 

I am trying to find/build a simple antenna to transmit in the 20-30 MHz
range. I have an HP RF signal generator with an N-type RF output
connection. I purchased an antenna from RadioShack but it only goes
down to 121 MHz for transmitting.

On the receiving end I have a scanner. I looked up info online for
building a zip antenna for receiving (I take it the built-in antenna
with my scanner, a Realistic Pro-2021, will not be adequate), but I
can't find any simple info on the best way to construct a simple Tx
antenna for 20-30 MHz that I can plug into my RF signal generator. Any
advice?

In case you are curious as to what I'm doing, I'm using the signal
generator to send out sine wave audio tones to various frequencies (as
in the Spiricom experiments), and have been successful at frequencies
above 121 MHz, but I don't have an antenna that goes below that
frequency.

Thanks in advance for any help.

PS I was able to pick up 121+ MHz frequencies on my scanner with the
built-in antenna even though I had to constantly readjust my Tx antenna
to transmit at various frequencies. Why did my scanner pick up those
frequencies without me having to readjust the antenna length, and will
a SWR with its own antenna be sufficient for picking up any SW signals
I transmit, or do I still need to build a receiving antenna?

grav

Transmitting SW antenna question - pls help
 

On 9 Aug 2006 12:37:14 -0700, wrote:

I am trying to find/build a simple antenna to transmit in the 20-30 MHz
range. I have an HP RF signal generator with an N-type RF output
connection. I purchased an antenna from RadioShack but it only goes
down to 121 MHz for transmitting.

On the receiving end I have a scanner. I looked up info online for
building a zip antenna for receiving (I take it the built-in antenna
with my scanner, a Realistic Pro-2021, will not be adequate), but I
can't find any simple info on the best way to construct a simple Tx
antenna for 20-30 MHz that I can plug into my RF signal generator. Any
advice?

In case you are curious as to what I'm doing, I'm using the signal
generator to send out sine wave audio tones to various frequencies (as
in the Spiricom experiments), and have been successful at frequencies
above 121 MHz, but I don't have an antenna that goes below that
frequency.

Thanks in advance for any help.

PS I was able to pick up 121+ MHz frequencies on my scanner with the
built-in antenna even though I had to constantly readjust my Tx antenna
to transmit at various frequencies. Why did my scanner pick up those
frequencies without me having to readjust the antenna length, and will
a SWR with its own antenna be sufficient for picking up any SW signals
I transmit, or do I still need to build a receiving antenna?

grav
http://www.cebik.com/a10/ant41.html

Transmitting SW antenna question - pls help
 

wrote:
Any advice?

CB antenna, good buddy. 10-4.

Transmitting SW antenna question - pls help
 

Transmitting SW antenna question - pls help
 

Try a dummy load with wires.


but make sure your SIG Gen. is a 50 ohm match.

Transmitting SW antenna question - pls help
 

Beloved Leader wrote:
wrote:
Any advice?

CB antenna, good buddy. 10-4.

So buying a CB, unhooking the antenna and connecting it to the signal
generator should do the trick? Seems too simple... any catches?

grav

Transmitting SW antenna question - pls help
 

Also, my scanner only goes down to 30 MHz. Since I will be transmitting
the signal from my rf sig gen to the receiving target in my own house,
will a simple SW radio work with its own built-in antenna?

Thanks for the input.

grav

Transmitting SW antenna question - pls help
 

On 10 Aug 2006 12:50:19 -0700, wrote:

Also, my scanner only goes down to 30 MHz. Since I will be transmitting
the signal from my rf sig gen to the receiving target in my own house,
will a simple SW radio work with its own built-in antenna?

Thanks for the input.

grav
What are you trying to prove?

Transmitting SW antenna question - pls help
 

wrote:
Beloved Leader wrote:
wrote:
Any advice?

CB antenna, good buddy. 10-4.

So buying a CB, unhooking the antenna and connecting it to the signal
generator should do the trick? Seems too simple... any catches?

Simpler than that. You don't need a CB (radio). All you need is a CB
radio antenna. Radio Shack et al. sell them for $20-30, or you can find
them at yard sales for a quarter.

Transmitting SW antenna question - pls help
 

I hope you are not transmitting on 121 MHz area. That is part of the
108 to 136 MHz aircraft band if I am not mistaken. 121.5 for instance
is an emergency frequency and it is monitored.

You will end up in the pokey for interfering with aeroplanes,,, watch out
they will call you a terrorist

Transmitting SW antenna question - pls help
 

Transmitting SW antenna question - pls help
 

What frequency do you suggest testing my equipment at? The antenna I
believe goes from 131 to 512 mhz. The allocation chart shows nearly
every frequency in that range in use for something. Would 140 mhz be
ok?

Also, I'm not really sure how far the signal is going. Using the line
of sight formula with how small the antenna is, I can't really see the
signal going beyond the remote area where I live (which is not close to
any airport). To test it I'd pretty much have to broadcast on an FM
station, get in my car, and drive until the signal isn't picked up, but
this too can be a risky venture.

grav

patrick jankowiak wrote:
I hope you are not transmitting on 121 MHz area. That is part of the
108 to 136 MHz aircraft band if I am not mistaken. 121.5 for instance
is an emergency frequency and it is monitored.

This chart may be helpful to avoid causing interference on sensitive
frequencies.
http://www.ntia.doc.gov/osmhome/allochrt.html

PJ

Transmitting SW antenna question - pls help
 

David wrote:

What are you trying to prove?

I've already proven my sig gen can transmit a signal to my scanner, but
I'm trying to get it to pick up at a far lower range (25-30 mhz), which
was used with the Mark IV device in the Spiricom experiments. If you're
not familiar with Spiricom, the best thing I can tell you is to watch
the movie "Frequency".

Transmitting SW antenna question - pls help
 

David wrote:

A signal generator is a piece of test equipment. It is not a
communications device.

For its normal use it's a piece of test equipment. But for the intended
experiment, it is the primary (and cheapest) way to send tones onto a
particular frequency to be recorded.

What happens when tones are sent to the frequency? Nothing. But in the
Mark IV experiments, they were a conduit for voices (allegedly
paranormal in nature) to materialize and a 2-way communication to take
place (versus the recording of white noise with a tape recorder, asking
questions, and having to stop the tape, play it back, and analyze it
with software, which most paranormal investigators realize is too
tedious and time-consuming and one-way in nature - more like email vs.
instant-messaging for paranormal communication).

grav

Transmitting SW antenna question - pls help
 

http://worlditc.org/h_07_meek_spiri_029_041.htm

Scroll down and see the schematic for the machine. What's interesting
is that they use 10-12 ft. antennas (which today could be replaced by
simple CB antennas).

For a more clear schematic and samples of the voice contacts using the
tones:

http://worlditc.org/k_06_spiricom.htm

Hope this helps you to get a better understanding of the equipment and
theory involved with this time-consuming research.

Jeff

Transmitting SW antenna question - pls help
 

wrote:
http://worlditc.org/h_07_meek_spiri_029_041.htm

Scroll down and see the schematic for the machine. What's interesting
is that they use 10-12 ft. antennas (which today could be replaced by
simple CB antennas).

For a more clear schematic and samples of the voice contacts using the
tones:

http://worlditc.org/k_06_spiricom.htm

Hope this helps you to get a better understanding of the equipment and
theory involved with this time-consuming research.

Jeff


Ok, well to me that is wierd but interesting. So, if it is not
strictly necessary to use any one RF frequency, perhaps, legalities
aside, it would do no harm to use one of the FRS channels. FRS is FM
and incoming signals should not disturb your AM experiments as long as
your receiver is close to the signal generator's antenna. I do not
imagine that any spirits would need a widely separated set of antennas
to fit between, so therefore a low power signal such as what comes out
of your signal generator should do for closelt spaced antennas. How
far apart? heck if I know. 2 feet? Since you are using a signal
generator, your power level can be very low so as to not interfere
with others, and an antenna for transmit or receive at those
frequencies need only be 4-5" long.

FRS:
462.5625 GMRS Simplex / FRS Ch. 1
462.5875 GMRS Simplex / FRS Ch. 2
462.6125 GMRS Simplex / FRS Ch. 3
462.6375 GMRS Simplex / FRS Ch. 4
462.6625 GMRS Simplex / FRS Ch. 5
462.6875 GMRS Simplex / FRS Ch. 6
462.7125 GMRS Simplex / FRS Ch. 7
467.5625 FRS Ch. 8
467.5875 FRS Ch. 9
467.6125 FRS Ch. 10
467.6375 FRS Ch. 11
467.6625 FRS Ch. 12
467.6875 FRS Ch. 13
467.7125 FRS Ch. 14

You might also try the "ISM" frequencies, as long as there are no big
machines operating on them and radiating powerful signals, you should
be fine. There is a listing of those frequencies he
www.tscm.com/FCC47CFRpart18.pdf

It seems to me the biggest challenge is to build the spectrum
generator for all those audio tones. Perhaps an old electronic organ,
one with the feature of a separate tone oscillator for each key, could
be used. You can pick off the sinewaves at the oscillators if it is an
old enough model.

PJ

Transmitting SW antenna question - pls help
 

legalities has nothing to do with it.We all have the right to listen to
any and all radio transmissions in the World.There are some certain
transmissions however,you better not blab to anybody about.
cuhulin