Looks like I have a reprieve. Today is considered a half day for
student due to snow, so my presentation got cancelled. Which
is a good thing too, cause I'm quite unprepared for it.

Being the only Extra, let alone ham, in the area is a very
overwhelming feeling.

This whole thing needs to be rethought anyway. If anyone
has bits and pieces of working homebrew I can borrow,
say yes here and I will contact you privately. My own
homebrew is just not working today worth a darn.

The Eternal Squire


On Jan 31, 10:20 am, wrote:
HP,

The whole point of my original post was to see if forming a micropower
net on 80M COULD be done within the rules. I would indeed be a poor
mentor
for encouraging students to break the rules... and I never advocated
such. Please speed-read what I post a little slower next time

Today I make my first presentation, and I have a pretty bad cold.
I don't have any Mr. Wizard exhibits put togther, just the equivalent
of a slide show plus a few parts, because I only have a week's notice.

I am changing tack and taking my radio with me to the classroom,
if the students are really interested I will lend the classroom my rig
until
a replacement can be build or bought, and be with them for a couple
hours per week as control operator. The science teacher has
promised it could be connected outside to a wire antenna of some type
if at all possible.

So wish me luck, and please use my handle on Usenet rather than
my name from now on. I'd rather not be made by some determined
lunatic intent on causing me or my family any harm.

On Jan 30, 8:46 pm, "H. P. Friedrichs" wrote:

Very well.

Andrew,

A few thoughts about your idea and some of the responses that it has evoked:

First off, I don't think your emphasis should be on transmitting. To me,
ham radio is about communication, and communication, first and foremost,
is about LISTENING. Listening is what you should emphasize.

Since there are both physical laws of nature and interference (natural
and man-made) to contend with, the real magic in radio is the antenna,
amplifier(s), filter(s), and operator techniques used to extract useful
information from a feeble signal. (Case in point: Voyager 1 is now more
than 9 BILLION miles from earth, but as long as its flea-power
transmitter holds out, we expect to be able to continue receiving data.)

There is great fun in building simple receivers, and much to be learned.
A few years back, for lack of something better to do one evening, I
knocked together a regenerative set on the bench top in the garage. I
wound a coil on a toilet paper tube, made a grid-leak capacitor out of a
couple of microscope slides and some foil, and hooked up an old #26
tetrode. The rig was "wired" with alligator leads and powered by
flashlight batteries. The antenna was 15 feet of wire thumb tacked to
the garage ceiling, and the ground was a 'gator clip attached to the
cover plate screw of a nearby outlet. A few adjustments later and I
found myself listening to a radio-theater presentation of "Dracula" put
on by the BBC in London. That's more than 5000 miles from where I live.
That's magic.

In your case, a FET based regenerative set would be the ticket. Dirt
cheap and effective enough to be useful. (I'm thinking something along
the lines of 1 FET RF/isolation, 1 FET regen stage, and an LM386 amp
chip, which will easily drive common walkman-style headphones.)

If you want to teach your kids Morse, use the Code Quick method. Buy a
copy of a program called Numorse for yourself, and use this to generate
exercises for the kids. You can put the audio on cassette tape or CD's.
When they get up to 5 WPM or so, you have them listen to W1AW. The day
after a W1AW session you ask the kids some specific question about the
text that was sent the previous night. Offer prizes or some kind of
encouragement for positive responses. Once they can receive Morse,
learning to send is rather easy.

This is something of a detour, but have you ever heard recordings of
sounds the Ionosphere makes? Remarkable chirps, whistles, clicks, and
pops. Slow down the recordings and you get sounds that are startlingly
similar to the songs of certain birds, or the calls of whales. The
equipment to capture this is cheap and easy to build. This is one
situation where a remote location is a real asset, because there is far
less man-made electrical noise to foul your recordings. Get a kid
hooked on something like this, and who knows what kind of scientific or
technical career could develop from this experience.

If you insist on transmitting, or equipping your students to transmit
before they even have the skills to do so properly, fine, so long as you
are certain that your activities are within the boundaries of the law.
With regard to the comments of some in this thread I will simply say
that the last thing society needs is a "mentor" whose first lesson will
essentially be: "If you don't like the rules just ignore them." I am of
the opinion that the preponderance of this attitude is responsible for
much of the unhappiness in this world.

Final thought. I few years back I authored a book on the subject of
primitive radio, and how to build radio components from scratch. This
includes homemade variable capacitors, tuning coils, detectors, and even
headphones. The equipment is built with hand tools and made from such
mundane source material as wood, tin cans, cabinet magnets, and
cigarette lighter parts.

Web link: http://www.hpfriedrichs.com/bks-votc.htm

This book has been critically acclaimed by the editors of QST and
Practical Wireless in the U.K., and is recommended by at least one
teacher's guide:http://www.libraryvideo.com/guides/N...EATDCXALG28J0F...

I am sensitive to educational and charitable concerns. If you should
express serious interest in using these in a classroom setting, we could
discuss how to make this happen.

73

H P "Pete" Friedrichs
AC7ZL

wrote:
The why not say it here?

The Eternal Squire

On Jan 29, 6:06 pm, "H. P. Friedrichs" wrote:

Squire---

I tried to email you....it bounced back.

Pete
AC7ZL

wrote:

The Dine' (I use the term Navajo because most people outside are
more familiar with that) are a very proud people who would resent
being made fun of like that.

To the Dine', we are an alien people out of touch with the
rhythms of the land, who are obsessed with consumer goods,
technology, money, or bigotry. Even such whites are ourselves
who do see what history has done to the Dine' and find it
appalling, are viewed as possibly having egotism.

The Dine' are more impressed by whites who listen first then
act later in small ways that fit what the Dine' already do.

You have to live with the Dine' least a couple years before you
can even begin to understand the challenge of introducing a
new technology in a culturally appropriate manner.

The Eternal Squire

On Jan 29, 8:50 am, "RST Engineering" wrote:

That's true. They sent one kid off to MIT and he came back with a degree in
Electrical Engineering. When he got back home he found that the communal
restroom had no lights, so to show his gratitude to the tribe he ran
electricity to the bathroom.

So far as we know, that was the first Indian ever to wire a^head for a
reservation.

{;-)

Jim

"John Smith I" wrote in ...

Some reservations have sent men to the best colleges and have some of the
best attorneys in the world.

wrote:
HP,

The whole point of my original post was to see if forming a micropower
net on 80M COULD be done within the rules. I would indeed be a poor
mentor
for encouraging students to break the rules... and I never advocated
such. Please speed-read what I post a little slower next time

Squire,

With all due respect, you need to re-read *my* post. I never accused you
of anything. Rather, I indicated up front that my comments were directed
both to you and to others in this thread, some of whom have advocated an
"it is easier to get forgiveness than permission" point of view. I think
you've agreed that this is not appropriate for a mentor/teacher/role-model.

H. P. "Pete" Friedrichs
AC7ZL

wrote:

Squire-

I'm going to take your comment on face value and assume that your
receiver is indeed functional but for lack of proper regeneration. If
this is the case, I would guess that the most common cause of this kind
of problem is improper phasing of your tuning/ticker coils.

It would help if you could post or point to a schematic from which you
worked, but let me suggest this. Lift both leads from you tickler
winding and then swap them. This may be all it takes to fix the problem.

BTW: Check out this simple receiver by Charles, N1TEV. It follows, more
or less, the architecture I proposed, and apparently works well. PCBs
are available.

http://www.electronics-tutorials.com...o-receiver.htm

Here is a simpler circuit by regenerative radio guru C. F. Rocky.

http://www.mines.uidaho.edu/~glowbugs/FETREGN2.gif

H.P. "Pete" Friedrichs
AC7ZL



Well, I did try to build a regenerative receiver to demonstrate to the
class,
but I couldn't get regeneration. Shall I mail it to you to see if you
can debug it?

Thanks,

The Eternal Squire

a cheap ready-made lofer coil is right in an old junker tv..the horizontal
output coil usually has a ferrite adjustment for frequency (horizontal
hold)... put another one in series with your 50 foot antenna, and tune that
as your load for increased output. I bet you can even use one for a cheapie
regen radio down there too...Hmmm time to visit the dump..
............

"N9WOS" wrote in message
...

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.

On Jan 25, 9:23 pm, wrote:
All,

I have a situation, and would like some opinions rather than flames on
how to handle it. My wife teaches at a public school just off the
Easter Arizona Navajo reservation. Lately, a junior school science
teacher is starting up a science club and has asked me to provide for
the amateur radio side of the club and be its control operator.

She believes that the kids would be fascinated by the Morse code -
Dxing - Construction end of the hobby, even though Morse is no longer a
required test element.

The kids are mostly Navajo and thusly have a very limited technological
background (hence the reason for the club to stir the interest), so I
need something concrete with immediate payoff to keep their interest
hooked while getting them as ready as I can to write their Technician
exam. The nearest VEC is 4 hours away and I'd rather have as few fail
as possible.

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

First, Good SHow on trying to interest the kids.

Secondly, have you investigated 160-190 KHz as an option. The transmit
antenna would be limited in length to a max of 50 feet but the receive
antenna can be tuned dipoles. The transmitter is limited to 1 watt
output so it will be a heck of a lot easier to measure then the Low
power Part 15 devices. If they live in a rural area they should have
little manmade noise to contend with. Tuning the receiver and
transmitter can be done with an oscope and low frequency generator.
The other thing is the receiver can use a block converter with an AM
radio.