I had thought to start an unlicensed micro-power code practice net
whose range would be limited to about a 30 mile radius, which is about
the size of the local reservation right next to the school.

What I want to do is provide each kid with a popcorn CW transceiver for
the colorburst frequency (3579 khz), a key, a short random wire, and a
battery. That way they could practice amongst themselves with
myself as occasional net control.

My question is this: so long as final output to the antenna is within
the requirement of part 15 unlicensed operation, is part 15 unlicensed
operation allowed within a band normally governed under part 97?
Part 15 operation would easily cover a 30 mile radius on 80M.

If no, I'll run the net under part 15 on the edge of the AM band near
160M.

Thanks in advance,

The Eternal Squire


I have been thinking about this for a while before making this reply.

I would strongly suggest looking at the lowfer band.
160Kc to 190Kc
The limitations are relatively straight forward.
Maximum length of feed line, and antenna are 15meters.
Maximum power input to the final amp stage is 1W.
No other real limitations besides the fact that out of band emissions have
to be below a specific point.

That is about a 50 foot long antenna. There isn't much of a chance that they
will try to string one up longer than that, unless they were really
industrious.
And they can learn about antenna loading, to get a better transmitted
signal/range.

The one watt input power level is easy to determine. If the input is 10V
then adjust the current to a maximum of 100mA.

They can use any mode of communication they want. CW, AM, SSB, FM, PSK31,
BPSK, MFSK
The sky is the limit as for as modes.

If they have computers, most of the digital modes can be implemented with
soundcard based communications software that is available as freeware
Look up "MULTIPSK"

They can set up beacons for propagation checks, or talk to each other in
real time.

30 miles is an easy distance to reach with basic loaded antennas. Especially
with PSK31 and CW.

It will allow them to learn how to build receiving antennas.

And if they can't reach, or hear someone on the other side of the
reservation, then it will allow them to learn the basics of traffic handling
by the stations in the middle relaying information from one station to
another.

It will also teach them the basics of the narrower bandwidth/greater range
relationship. With the low bandwidth BPSK, PSK31 modes, they will easily
communicate across the reservation even if they can barely hear each other
on voice.

You can either get kit equipment for receiving or transmitting, which is
widely available on line. Or you can design and build your own.

If they are lucky, they may even hear stations, and beacons from hundreds of
miles away. Or even thousands. There is nothing like the thrill of DX.

N9WOS wrote:


I have been thinking about this for a while before making this reply.

I would strongly suggest looking at the lowfer band.
160Kc to 190Kc
The limitations are relatively straight forward.
Maximum length of feed line, and antenna are 15meters.
Maximum power input to the final amp stage is 1W.
No other real limitations besides the fact that out of band emissions have
to be below a specific point.

That is about a 50 foot long antenna. There isn't much of a chance that they
will try to string one up longer than that, unless they were really
industrious.
And they can learn about antenna loading, to get a better transmitted
signal/range.

The one watt input power level is easy to determine. If the input is 10V
then adjust the current to a maximum of 100mA.

They can use any mode of communication they want. CW, AM, SSB, FM, PSK31,
BPSK, MFSK
The sky is the limit as for as modes.

If they have computers, most of the digital modes can be implemented with
soundcard based communications software that is available as freeware
Look up "MULTIPSK"

They can set up beacons for propagation checks, or talk to each other in
real time.

30 miles is an easy distance to reach with basic loaded antennas. Especially
with PSK31 and CW.

It will allow them to learn how to build receiving antennas.

And if they can't reach, or hear someone on the other side of the
reservation, then it will allow them to learn the basics of traffic handling
by the stations in the middle relaying information from one station to
another.

It will also teach them the basics of the narrower bandwidth/greater range
relationship. With the low bandwidth BPSK, PSK31 modes, they will easily
communicate across the reservation even if they can barely hear each other
on voice.

You can either get kit equipment for receiving or transmitting, which is
widely available on line. Or you can design and build your own.

If they are lucky, they may even hear stations, and beacons from hundreds of
miles away. Or even thousands. There is nothing like the thrill of DX.



Yanno, that is damn good thinking. I haven't played in the lowfer freqs
for ages.

Regards,
JS

You can either get kit equipment for receiving or transmitting, which is
widely available on line. Or you can design and build your own.

Maybe I should clarify one of my statements before someone calls me stupid.

I mean easily modifiable equipment is widely available online.
It isn't sold for Lowfer operation.

Most heterodyne and direct conversion based short wave, receiving kits can
be modified over to the LF band from 160 to 190kc

On a 455kc heterodyne receiver, push the local oscillator down to 615 to 645
kc, and put a band pass network on the input peaked to the lowfer band, and
you are done.

Same thing can be done for SSB transmitter kits that use a fixed transmit IF

N9WOS wrote:
You can either get kit equipment for receiving or transmitting, which is
widely available on line. Or you can design and build your own.

Maybe I should clarify one of my statements before someone calls me stupid.

I mean easily modifiable equipment is widely available online.
It isn't sold for Lowfer operation.

Most heterodyne and direct conversion based short wave, receiving kits can
be modified over to the LF band from 160 to 190kc

On a 455kc heterodyne receiver, push the local oscillator down to 615 to 645
kc, and put a band pass network on the input peaked to the lowfer band, and
you are done.

Same thing can be done for SSB transmitter kits that use a fixed transmit IF



Only thing is, such low power xmitters, if designed and tuned to a
"quiet" portion of the mw band allows anyone with a standard am radio to
tune into and participate in ...

Rip apart any old transistor radio and you have the necessary parts for
the xmitter ...

VLF receivers can be a tad bit expensive ... however, most am radios
would easily be modified to VLF ... the patience of the elmer would be
the only resource in question.

Regards,
JS

Only thing is, such low power xmitters, if designed and tuned to a
"quiet" portion of the mw band allows anyone with a standard am radio to
tune into and participate in ...

Rip apart any old transistor radio and you have the necessary parts for
the xmitter ...

VLF receivers can be a tad bit expensive ... however, most am radios
would easily be modified to VLF ... the patience of the elmer would be
the only resource in question.

Regards,
JS

The first thing that came into my mind when I read that is.
Is there even such thing as a "quiet portion of the MW band"?

The normal AM band has so many multiKW stations running on it that it is
heavily polluted with RF noise.
The general coverage receiver I have, has a 200 Foot long antenna hooked to
it.
Night or day, It is hard to find a broadcast channel that isn't giving a
signal reading running from S5 to S9 even when you can't hear any traces of
a broadcast signal.
There is so many distant stations being heard at once that it turns into
indistinguishable noise.

And if you do catch a quiet channel, it only last for a few minutes, or
hours until propagation changes, and the noise level comes back up to
normal.

Once you drop off the edge of the AM band, the average noise level drops
down to almost nothing within a few Kc of the edge.

After you get past a certain grade of radio and RX antenna, you will not
gain any improvement because of the base noise level of the band. They would
basically be reduced to fighting the TX side of things, to try and stay
above the average noise level.

Can you say "CB a few years ago"?

The only reason the horrible noise level isn't apparent on most AM receivers
sold in stores, is because they are so insensitive that they can't hear even
relatively loud signals. That is why I almost consider it a waste of money
to buy a standard AM/FM radio that is currently on the market to listen to
AM. I have built crystal radios that are more sensitive on AM than some of
the high dollar AM/FM radios I have used.

A lot of AM/FM radios I see any more, don't even have an IF section, with IF
transformers. If you are lucky, they have a 455kc crystal filter, in a
section that can barely be called a IF section.

You are taking a big handicap when you stay on the AM band, and use a
standard off the shelf AM radio.

You have to use a radio that is designed for SW use, where the average noise
levels are a lot lower, better selectivity, and the radio has a higher total
gain from antenna to speaker.

If I was designing a simple software IF radio for them to use with their
computer, Or a basic SSB voice rig, here is the basic layout i would use.

The IF for receive and TX would be 455Kc using off the shelf AM IF cans.

TX side.
450Kc or 460Kc crystal feeding a balanced modulator.
Soundcard driving the other input of the balanced modulator.
Feed the output of the modulator through an amplifier to an off the shelf
455Kc center frequency, 10Kc bandwidth, crystal filter used in the IF of
standard AM receivers.

Feed that into a mixer being driven by a 630kc local oscillator.
That will yield a 170Kc to 180kc coverage signal that you can feed into a
band pass filter.
Feed the band pass filter into the final amp.
Feed the final amp into the antenna coupler/ second band pass filter, and
then to the antenna.

That will allow you to use about 1/3 of the entire lowfer band without
changing any frequency in the transmitter.

Just set up the receiver with the exact opposite of the TX.
And you can use the TX crystal oscillators to feed the receiver, so the RX
frequency will be a mirror of the TX one.

The antenna coming in to a band pass filter.
One stage of RF amp if desired.
Feed that into the RX mixer.
The mixer uses the same 630Kc local oscillator as the TX section.
Run the output of the mixer into an IF strip, with an identical 455Kc
crystal filter.
Run it to a final detector being feed by the 450/460Kc crystal.
Feed the output of a detector into an audio amp, then to the input of the
sound card.
Put a little AGC in here and there, and you are ready to go.

With that setup, they could have several conversations going at once on
different digital modes, without bothering each other.

For an AM transmitter I would just use a crystal oscillator driving a
modulated final amp.
And for the receive end, I would just use a modified AM receiver with a GOOD
IF!!!. There is even a few general coverage radios that already has 160 to
190Kc coverage that would work fine for a receiver..

N9WOS wrote:
Only thing is, such low power xmitters, if designed and tuned to a
"quiet" portion of the mw band allows anyone with a standard am radio to
tune into and participate in ...

Rip apart any old transistor radio and you have the necessary parts for
the xmitter ...

VLF receivers can be a tad bit expensive ... however, most am radios
would easily be modified to VLF ... the patience of the elmer would be
the only resource in question.

Regards,
JS

The first thing that came into my mind when I read that is.
Is there even such thing as a "quiet portion of the MW band"?

The normal AM band has so many multiKW stations running on it that it is
heavily polluted with RF noise.
The general coverage receiver I have, has a 200 Foot long antenna hooked to
it.
Night or day, It is hard to find a broadcast channel that isn't giving a
signal reading running from S5 to S9 even when you can't hear any traces of
a broadcast signal.
There is so many distant stations being heard at once that it turns into
indistinguishable noise.

And if you do catch a quiet channel, it only last for a few minutes, or
hours until propagation changes, and the noise level comes back up to
normal.

Once you drop off the edge of the AM band, the average noise level drops
down to almost nothing within a few Kc of the edge.

After you get past a certain grade of radio and RX antenna, you will not
gain any improvement because of the base noise level of the band. They would
basically be reduced to fighting the TX side of things, to try and stay
above the average noise level.

Can you say "CB a few years ago"?

The only reason the horrible noise level isn't apparent on most AM receivers
sold in stores, is because they are so insensitive that they can't hear even
relatively loud signals. That is why I almost consider it a waste of money
to buy a standard AM/FM radio that is currently on the market to listen to
AM. I have built crystal radios that are more sensitive on AM than some of
the high dollar AM/FM radios I have used.

A lot of AM/FM radios I see any more, don't even have an IF section, with IF
transformers. If you are lucky, they have a 455kc crystal filter, in a
section that can barely be called a IF section.

You are taking a big handicap when you stay on the AM band, and use a
standard off the shelf AM radio.

You have to use a radio that is designed for SW use, where the average noise
levels are a lot lower, better selectivity, and the radio has a higher total
gain from antenna to speaker.

If I was designing a simple software IF radio for them to use with their
computer, Or a basic SSB voice rig, here is the basic layout i would use.

The IF for receive and TX would be 455Kc using off the shelf AM IF cans.

TX side.
450Kc or 460Kc crystal feeding a balanced modulator.
Soundcard driving the other input of the balanced modulator.
Feed the output of the modulator through an amplifier to an off the shelf
455Kc center frequency, 10Kc bandwidth, crystal filter used in the IF of
standard AM receivers.

Feed that into a mixer being driven by a 630kc local oscillator.
That will yield a 170Kc to 180kc coverage signal that you can feed into a
band pass filter.
Feed the band pass filter into the final amp.
Feed the final amp into the antenna coupler/ second band pass filter, and
then to the antenna.

That will allow you to use about 1/3 of the entire lowfer band without
changing any frequency in the transmitter.

Just set up the receiver with the exact opposite of the TX.
And you can use the TX crystal oscillators to feed the receiver, so the RX
frequency will be a mirror of the TX one.

The antenna coming in to a band pass filter.
One stage of RF amp if desired.
Feed that into the RX mixer.
The mixer uses the same 630Kc local oscillator as the TX section.
Run the output of the mixer into an IF strip, with an identical 455Kc
crystal filter.
Run it to a final detector being feed by the 450/460Kc crystal.
Feed the output of a detector into an audio amp, then to the input of the
sound card.
Put a little AGC in here and there, and you are ready to go.

With that setup, they could have several conversations going at once on
different digital modes, without bothering each other.

For an AM transmitter I would just use a crystal oscillator driving a
modulated final amp.
And for the receive end, I would just use a modified AM receiver with a GOOD
IF!!!. There is even a few general coverage radios that already has 160 to
190Kc coverage that would work fine for a receiver..




You have presented the above well, I am in agreement ...

The world is always a compromise between what one wants and what is
actually to be had.

Too bad there are none of the dollar-ninety-eight kits out there--like
there was when I as a boy. (or tons of old military equipment to be had
for a song)

Warmest regards,
JS

"N9WOS" ) writes:

The first thing that came into my mind when I read that is.
Is there even such thing as a "quiet portion of the MW band"?

The normal AM band has so many multiKW stations running on it that it is
heavily polluted with RF noise.

The solution is actually simpler.

Since realistically the kids don't need to communicate before they actually
can, they need to receiver code practice. There is, again, ample chance
to convey the hobby to them before they pursue licenses, and once they
have licenses pretty much "anything goes" because of the very nature of
amateur radio.

The solution is to get the community involved. These are their kids,
they want them to do well in the world. Presumably there is a radio
station on the reserve specifically for the reservation. So get some
space there to send code (obviously a code practice oscillator into the
microphone input) for a bit. It could even be as simple as
a few sentences every day at a fixed time, the same way Jean Sheppard
wrote of getting secret messages during the "Little Orphan Annie" show.
The reservation near here has bingo games on the air every Sunday night,
so why shouldn't a community that is interested in the success of their
young not see the point of sending some morse code over the local station?

The point isn't to give them amateur radio before the fact, it's to lure
them in.

And if there's no community radio station on that reserve, then I suspect
that's of more value than low power stations that may turn out to be a dud.
Because a community station can do so much for the community. And one might
as well get those interested students involved in the project.

A few years back, at that nearby reserve that has radio bingo, one 13 year
old lamented that there was no library on the reserved. They have a library
now, it carries her name. This is something that is going to last forever
(or hopefully so), and is the sort of thing reserves need. Libraries
are places where people can find those books about radio and electronics
when they suddenly become interested, or lure them in when they stumble
on such things.

Getting the kids interested in science and even specifically electronics
is a good thing. Done well, it will even benefit them if they don't
pursue such things later, because the teaching becomes a catalyst for
other things.

But sometimes one has to look at projects and wonder if they will really
make change, or if they are just neat in themselves but will actually
bomb (because the kids lose interest, or because all kinds of money and
resource is put it into something when there are simpler things to do
the same thing).

Michael VE2BVW

Its a good idea, might even make a fine commercial venture. My only
problem
with 160 to 190 khz is that its a public band, not an amateur band.

My reason for operating 80M under part 15 is that as a code practice
group
they can get used to courtesy and usage as well as operation, and
anyone
who happens to listen will simply hear just another group of brass
pounders.

Immediately after getting the license they can keep the same rigs but
then
start an amplifier project.

Another question would be temporary callsigns. I was thinking that
each kid
would have the call 15XX, where XX is the first and last initial.

On Jan 27, 3:20 pm, "N9WOS" wrote:
Only thing is, such low power xmitters, if designed and tuned to a
"quiet" portion of the mw band allows anyone with a standard am radio to
tune into and participate in ...

Rip apart any old transistor radio and you have the necessary parts for
the xmitter ...

VLF receivers can be a tad bit expensive ... however, most am radios
would easily be modified to VLF ... the patience of the elmer would be
the only resource in question.

Regards,
JSThe first thing that came into my mind when I read that is.
Is there even such thing as a "quiet portion of the MW band"?

The normal AM band has so many multiKW stations running on it that it is
heavily polluted with RF noise.
The general coverage receiver I have, has a 200 Foot long antenna hooked to
it.
Night or day, It is hard to find a broadcast channel that isn't giving a
signal reading running from S5 to S9 even when you can't hear any traces of
a broadcast signal.
There is so many distant stations being heard at once that it turns into
indistinguishable noise.

And if you do catch a quiet channel, it only last for a few minutes, or
hours until propagation changes, and the noise level comes back up to
normal.

Once you drop off the edge of the AM band, the average noise level drops
down to almost nothing within a few Kc of the edge.

After you get past a certain grade of radio and RX antenna, you will not
gain any improvement because of the base noise level of the band. They would
basically be reduced to fighting the TX side of things, to try and stay
above the average noise level.

Can you say "CB a few years ago"?

The only reason the horrible noise level isn't apparent on most AM receivers
sold in stores, is because they are so insensitive that they can't hear even
relatively loud signals. That is why I almost consider it a waste of money
to buy a standard AM/FM radio that is currently on the market to listen to
AM. I have built crystal radios that are more sensitive on AM than some of
the high dollar AM/FM radios I have used.

A lot of AM/FM radios I see any more, don't even have an IF section, with IF
transformers. If you are lucky, they have a 455kc crystal filter, in a
section that can barely be called a IF section.

You are taking a big handicap when you stay on the AM band, and use a
standard off the shelf AM radio.

You have to use a radio that is designed for SW use, where the average noise
levels are a lot lower, better selectivity, and the radio has a higher total
gain from antenna to speaker.

If I was designing a simple software IF radio for them to use with their
computer, Or a basic SSB voice rig, here is the basic layout i would use.

The IF for receive and TX would be 455Kc using off the shelf AM IF cans.

TX side.
450Kc or 460Kc crystal feeding a balanced modulator.
Soundcard driving the other input of the balanced modulator.
Feed the output of the modulator through an amplifier to an off the shelf
455Kc center frequency, 10Kc bandwidth, crystal filter used in the IF of
standard AM receivers.

Feed that into a mixer being driven by a 630kc local oscillator.
That will yield a 170Kc to 180kc coverage signal that you can feed into a
band pass filter.
Feed the band pass filter into the final amp.
Feed the final amp into the antenna coupler/ second band pass filter, and
then to the antenna.

That will allow you to use about 1/3 of the entire lowfer band without
changing any frequency in the transmitter.

Just set up the receiver with the exact opposite of the TX.
And you can use the TX crystal oscillators to feed the receiver, so the RX
frequency will be a mirror of the TX one.

The antenna coming in to a band pass filter.
One stage of RF amp if desired.
Feed that into the RX mixer.
The mixer uses the same 630Kc local oscillator as the TX section.
Run the output of the mixer into an IF strip, with an identical 455Kc
crystal filter.
Run it to a final detector being feed by the 450/460Kc crystal.
Feed the output of a detector into an audio amp, then to the input of the
sound card.
Put a little AGC in here and there, and you are ready to go.

With that setup, they could have several conversations going at once on
different digital modes, without bothering each other.

For an AM transmitter I would just use a crystal oscillator driving a
modulated final amp.
And for the receive end, I would just use a modified AM receiver with a GOOD
IF!!!. There is even a few general coverage radios that already has 160 to
190Kc coverage that would work fine for a receiver..

Its a good idea, might even make a fine commercial venture. My only
problem
with 160 to 190 khz is that its a public band, not an amateur band.

My reason for operating 80M under part 15 is that as a code practice
group
they can get used to courtesy and usage as well as operation, and
anyone
who happens to listen will simply hear just another group of brass
pounders.

Immediately after getting the license they can keep the same rigs but
then
start an amplifier project.

Another question would be temporary callsigns. I was thinking that
each kid
would have the call 15XX, where XX is the first and last initial.

Ww wow wow wow.... put the brakes on here a second.

There is a little flaw with that logic.

People do listen around the band, and type up the callsigns on
websites/books/CD ROMs, and a lot of logging programs have callsign lookup,
or at least rough location determination based on call layout.

There is never "just another group of brass pounders"

There is plenty of people that operate at levels of a watt or less, with the
full knowledge that when they pound out a CQ a couple times, that someone,
or sometime a bunch of people, will be looking through the band, hear them,
and respond, so they can make a contact.

Local CW ops, and even some at quite a distance will quickly determine that
there has been a flood of "very strange, illegal, but slightly weak people
that don't do code very well" cluttering up a specific frequency, or cluster
of frequencies.

Of course, the operator/s will subsequently have kittens, and all attempts
to make ham radio operators look like a bunch of angles will go down the
drain.

Of course the operator/s will try to get the group of "freebanders" to
leave. If they don't listen, then the operator will do his solemn duty and
he will get reinforcements, and the frequency will sound like world war 25
has just broken loose, pronto.

Them using random, made up callsigns will speed up the process, because
there is plenty of people that cruse the bands, looking for rare DX. How do
you think pileups happen? When they find a weak station using a rare
callsign, it will hit the DX clusters, and all hell will break loose.

Heck, one of the groups that I always listen to on 160 had a little fun one
time. One of them made a joke by saying that he was (something thousand
miles) south east of anchorage Alaska. (ie) In Iowa. And all of a sudden,
there were tons of people on the frequency asking where the Alaskan station
was. And carnage issued. Some casual passer by had heard the Alaska
reference and forwarded it to the DX clusters.

I can see so many ways that that setup could lead to total carnage in so
many ways.

You will have some poor child asking his parents why someone would want them
to stick such and such in up their tail end.

Would a call sign like PART15XX make it a lot clearer and a lot more
obvious? I wonder what the FCC would suggest for micropower
CW callsigns.


On Jan 28, 5:40 pm, "N9WOS" wrote:
Its a good idea, might even make a fine commercial venture. My only
problem
with 160 to 190 khz is that its a public band, not an amateur band.

My reason for operating 80M under part 15 is that as a code practice
group
they can get used to courtesy and usage as well as operation, and
anyone
who happens to listen will simply hear just another group of brass
pounders.

Immediately after getting the license they can keep the same rigs but
then
start an amplifier project.

Another question would be temporary callsigns. I was thinking that
each kid
would have the call 15XX, where XX is the first and last initial.Ww wow wow wow.... put the brakes on here a second.

There is a little flaw with that logic.

People do listen around the band, and type up the callsigns on
websites/books/CD ROMs, and a lot of logging programs have callsign lookup,
or at least rough location determination based on call layout.

There is never "just another group of brass pounders"

There is plenty of people that operate at levels of a watt or less, with the
full knowledge that when they pound out a CQ a couple times, that someone,
or sometime a bunch of people, will be looking through the band, hear them,
and respond, so they can make a contact.

Local CW ops, and even some at quite a distance will quickly determine that
there has been a flood of "very strange, illegal, but slightly weak people
that don't do code very well" cluttering up a specific frequency, or cluster
of frequencies.

Of course, the operator/s will subsequently have kittens, and all attempts
to make ham radio operators look like a bunch of angles will go down the
drain.

Of course the operator/s will try to get the group of "freebanders" to
leave. If they don't listen, then the operator will do his solemn duty and
he will get reinforcements, and the frequency will sound like world war 25
has just broken loose, pronto.

Them using random, made up callsigns will speed up the process, because
there is plenty of people that cruse the bands, looking for rare DX. How do
you think pileups happen? When they find a weak station using a rare
callsign, it will hit the DX clusters, and all hell will break loose.

Heck, one of the groups that I always listen to on 160 had a little fun one
time. One of them made a joke by saying that he was (something thousand
miles) south east of anchorage Alaska. (ie) In Iowa. And all of a sudden,
there were tons of people on the frequency asking where the Alaskan station
was. And carnage issued. Some casual passer by had heard the Alaska
reference and forwarded it to the DX clusters.

I can see so many ways that that setup could lead to total carnage in so
many ways.

You will have some poor child asking his parents why someone would want them
to stick such and such in up their tail end.