Transcript QRP and Home Brews presentation at the 2007 W.V.A.R.A

QRP and Home Brews
presentation at the
2008 W.V.A.R.A. HAMFEST
March 8, 2008
John Swez
KC9JPZ
URL for download of this Presentation
newton.indstate.edu/swez
This talk consists of four parts
• An introduction to QRP
• An introduction to the speaker
• The RAMSEY 40 meter low power kit and
testing
• Small Magnet Noise Reduction Antenna and
testing
January 24th on eHam.net
So Now You're HF-Active
KE5FRF encourages you to still learn Morse Code.
So Now You're HF-Active Reply by WA0ZZG on January 18, 2007
Mail this to a friend! Last winter, on a night that was below zero, I was
tuning around 40 meters on a little QRP CW rig. Found a slow station,
not very strong, calling CQ. I went back to him. Talked for about 45
minutes to a older gentleman from Atlanta. I felt good about making the
contact with only four watts, so I told him how much power I was
running. He completely deflated my balloon by coming back and telling
me "that’s OK I am running one half watt."
Dave
WA0ZZG
To be classified as QRP your power level must not exceed 5 watts output
when transmitting a CW signal.
“Borrowed From” New Jersey QRP Club http://www.njqrp.org/whyqrp/2.htm
One of the first Commandments of
QRPing
K.I.S.S. Use a simple dipole up in the tree
Reference: Same article as previous slide
Look! If you only got a few watts, make sure it gets up into the sky!
Most QRP QSOs are CW QSOs (we
will talk about QRP Math later
Another Introduction to QRP from a well known HAM
"Welcome to the realm of QRP, a place where less RF power is more
fun for the operator! In general, QRP operators use equipment that
weighs less, takes up less space, costs less and is less dependent on
ac power than the typical ham station of 50 watts or more. In return,
QRP enthusiasts get freedom - freedom to carry a complete station, with
accessories and antenna, in a briefcase.
A typical QRP station is small enough to take along on vacation in a car
full of family, by air or backpacking. Your QRP station can operate from
batteries for long periods when the power fails, or indefinitely from
unusual power sources such as private hydroelectric, wind or solar
power systems.
Freedom is gratifying, but better still is the sense of accomplishment
that comes from operating equipment you built yourself. You may best
love the feeling when that first CQ from your home-built transmitter is
answered - or the way a smile steals onto your face when that 1-KW
station gives your 1-W transmitter a 599 report."
- Dave Sumner, K1ZZ -
From VE6BPR’s Home Page http://www.qsl.net/ve6bpr/ About QRPer’s
"What motivates the low-power (QRP) amateur operator? This
question does not have a simple answer. A vast number of QRPers
are "turned on" by the relative simplicity of most home-made QRP
equipment. Simple gear is not only easy to construct and operate,
but it is fairly inexpensive to build. This has a special appeal to those
who lack technical backgrounds and have yet to develop their skills.
Furthermore, many of published QRP circuits may be assembled on
a PC (printed circuit) board that is available by mail from one or
more PC-board vendors. The parts-placement guide for a given
project is generally published in the related article. Guesswork is
thus eliminated for the most part.”
“Other amateurs have the ability to design their own circuits. QRP
equipment offers a short-term exercise in the workshop because
many of the projects are simple. This enables an experimenter to try
new circuits in an evening or within a couple of days. He can try new
ideas and obtain fast results1. He may continue to work with his new
circuit until it is perfected at which time a final model can be built,
housed in a cabinet and used in his station.” 1 I (KC9JPZ)
recommend Experimental Methods in RF Design
-- by Wes Hayward, W7ZOI, Rick Campbell, KK7B, and Bob Larkin,
W7PUA published by ARRL It makes designing a snap.
“Other QRPers are captured by the nostalgia that takes them back to the
early days of Amateur Radio, when hams, through necessity, used only a
few watts of RF power for communicating. In other words, they had to do
things the hard way. Each successful QSO was logged as an
achievement! Pride accompanied home-made gear and the ability to be
heard at great distances. In general, QRPers are a special breed of
friendly operators. You have much to gain by getting involved in this
growing movement." - Doug DeMaw, W1FB In 1954 I was licensed as W3HUK. I received a conditional class license since in
those days you had to go to a city with an FCC examiner. My written and 13 wpm
code test was given to me from my cousin W3OAQ. My equipment consisted of a
Hallicrafters SX28A receiver (Super Sky-Rider) and a Heathkit DX 35 transmitter.
Although my 6146 final amplifier was capable of 65 Watts I usually ran 50 Watts
input to the final stage.
I built the Heathkit DX 35 as a kit by saving a lot of hard earned chores money while
living on a farm in Union Dale, PA. I first built a power supply from scratch as my first
practice in soldering. I remember the first time I turned it on “the plates glowed red”.
My cousin when immediately upon seeing this told me to “shut it off!” He later
discovered a blown out Pi network capacitor because I had selected too low of a
voltage! Hi Hi! I did better with the DX-35. I assembled the whole thing but it did not
work. No RF output. But the only mistake I made was applying too much soldering
heat to the RG-58U coax feed to the amphenol output connected on the rear of the
chassis. Not bad for a farm boy!
My rig in 1954
Heathkit DX-35
ARRL Field Day circa 195?
W3HUK
W3OAQ
Hallicrafters SX-28A Super Skyrider
International regulations state:
"All stations shall only use the
minimum power required for
effective communications."
My Dad’s farm was located in Northeastern Pennsylvania to the east of Elk
Mountain in Union Dale, PA. Our elevation was about 1,500 ft on the east slope.
Thus I had a clear shot facing New Jersey and New York City. My 80 meter and
40 meter dipoles and my 50 Watts would blow “cool kilowatters” transmitting from
apartment buildings in New York City “right out of the sky”.
How I (KC9JPZ) got back into Ham Radio in 2006
I was at my usual Tuesday night auction at the Shadow Auction Barn (1517
Maple Ave., Terre Haute) about two years ago. I had just gotten there.
There were two auctions going on in the “back room”. A young friend
(Andrew) yelled out to me when I got there. “Hey Doc! They’re auctioning off
a radio right now!” I looked around to my right and saw the auctioneer
holding up a Drake R8 Communications Receiver. I held up my hand and
got it for $3. The R8 Speaker went next. I had to pay $5 for that!
I took it home, hooked a short wire to it, and plugged it in. Low and behold
the LCD screen lit up and noise came out of the speaker. It worked! I got a
manual off the Web. The next day I found out there was not one thing wrong
with this receiver. Drake R8’s go on eBay for about $500 (if you can find
one!).
After a year or so of listening to it and especially the HAM bands, my code
came back and I was hooked again.
I was licensed as KC9JPZ in Summer of 2006. In fact,I took my General
Class exam at W.V.A.R.A. 2006 Field Day
How I got into QRP and why I chose Ramsey Kits
I did quite a bit of Ham Radio between the time of 1954 (8th grade) and
High School. I established many contacts. I think I remember almost
getting my WAS and having quite a bit of DXing for my DXCC. My pride
and joy was my QSL card from Eritrea (a small country just north of
Ethiopia). Unfortunately, after high school I entered Penn State University
and really did not lose interest in Ham Radio but lost all my time for it. Later
in life I was busy earning a living. Eventually I lost my license.
After my resurgence back into Ham Radio, I thought “why not do it again”
but this time make it more exciting and “QRP it.” Although I did buy an
ICOM 718 during the Fort Wayne Hamfest last year (which can be
adjusted to low power) as my main rig, my QRP endeavors would be left
to kit building and dragging my Drake R8 occasionally into the field
camping with a good deep cycle battery.
In my “younger days” I worked a lot of the 40 meter band. I then chose to
purchase the Ramsey QRP 40 meter transmitter because “The kit looked
attractive”.
Reference
http://www.qsl.net/ve6
bpr/qrpfreq.htm
To See The Enormous Growing Popularity of QRP
Go to
http://www.qsl.net/miqrpclub/li
nks.html the “chain locker” of
the Michigan QRP Club (to
see a list of clubs and kit
suppliers for QRP)
QRP isn't just about using low
power, it's about using simple
equipment (and simple
antennas.
Reference same as previous slide
Graph again courtesy of New Jersey QRP Club
CW vs SSB
http://www.njqrp.org/ and http://www.njqrp.org/whyqrp/whyqrp.htm (why QRP?)
Here’s a nice twist: a tube QRP Rig (glow-bug)
http://home.stny.rr.com/wa2ntk/qrp_1.htm
W2NTK circuits
Ramsey 40 m QRPc
Rig
Picture from Ramsey
Home Page
Manual at:
http://www.ramseyelectronics.com/down
loads/manuals/QRP40.pdf
Transistor circuit, oscillator, RF amp chain, and clean keying stage
RF output approx 1 Watt (.75W for QRP-20)
Pi-network output for good matching and harmonic suppression
Provision for two internal crystals, front panel switching
VCXO tuning, frequency can be tuned approx 7kHz around xtal freq.
(3.22 kHz with our rig)
My Ramsey QRP 40 Rig after
fabrication
Copied from Ramsey QRP
40 manual (Copyright
Ramsey, Inc.)
Ramsey QRP40 transmitter Block Diagram
54.3 Ohm Attenuator Used to Measure RF output
of Ramsey QRP40c Transmitter
Scope Settings: 0.1 uS
per division X and 2
V/division (Y) 1 division =
1 cm using a Tektronix
2205 Scope
V p-p output voltage versus Input voltage to transmitter using 54.3 ohm
termination and RG-58c (50 ohm impedance) cable to oscilloscope
Ramsey 40 meter QRP rig
y = 0.8226x + 4.803
R2 = 0.9763
RF output power (Watts)
17
0.70
16
0.60
15
0.50
14
13
12
0.40
0.30
0.20
11
0.10
10
0.00
7
9
11
Input Voltage (V)
13
15
y = 0.0521x - 0.1249
R2 = 0.9868
RF output (Watts)
peak to peak (V)
Output p-p versus Input Volts
7
9
11
13
input (volts)
RF power calculated as V(p-p)2/(8*53.4)
At 12.54 V input current
drain is 0.34 amps
From 2007 RF Experimenters Handbook
15
FFT Signal Analysis of QRP 40c Ramsey Transmitter using a A-M Systems
Model 3800 Digital Oscilloscope with Rectangular Math
Two repeat experiments at 13.69 Volts input. The rightmost
peak represents the 14.08 MHz first harmonic and the
fundamental is noted by the vertical dotted line.
The average of the two experiments show that the first harmonic is 32.6 dB down
Compliance of the Ramsey QRP 40c Rig with
Solution courtesy of
harmonic radiation
Mathematica 4.0
Frequency Stability Measurement of QRP 40 Rig
10 k tuning pot = 7040.631 kHz
Max CW and 7037.217 Max
CCW. Range = 3.414 kHz
Input to QRP Rig
Xtal osc pot at
max CW
Frequency (kHz) versus Temperature
Frequency vs Temperature of QRP Rig
y = 0.0003x + 7040.6
2
Frequency (kHz)
R = 0.034
7040.7
7040.69
7040.68
7040.67
7040.66
7040.65
7040.64
7040.63
7040.62
7040.61
7040.6
12
14
16
18
20
Temp (Degrees Celsius)
22
24
Summary of Ramsey QRP 40 Evaluation
• Maximum Output V (peak-peak) at 14 Volts = 16.2 V
• Maximum Output = 0.6 watts at 14 Volts DC input1
• Harmonic Output Crude Method: Relative signal strength (S
meter reading) S6 at 7040.39 kc (QRN bg = S3) with Harmonic #1 at
14.08078 with barely ¼ S unit above S3 background or = 13.6 dB down.
• Harmonic Output Sophisticated Method: First Harmonic 32.6
dB down; at ~ 0.6 Watt RF Output first harmonic power is only ~0.4 mW.
• Frequency Stability = Excellent (Std. Deviation only 4
Hertz over a Temperature Range of 15 oC to 21 oC.
• Tuning Range 3.414 kHz (full CW to full CCW of the
tuning pot)
1Actually
15 volts can be tested with the QRP 40 within specs but I chose
not to go this high
Ramsey Electronics SM100 Signal Magnet
Noise Reduction Antenna
• Tunes entire AM
broadcast band and can
be configured 500 kHz to
15 Mhz
• Faraday Shield eliminates
electrostatic noise
• Varactor diode tuning –
one wire connection 500’
• Low noise high gain FET
preamplifier circuit
• Rugged antenna
enclosure constructed
from PVC pipe
• Directional properties of
antenna helps to “null”
overpowering stations
Signal Magnet Noise Reduction Antenna
Schematic
Top: Antenna Assembly
Bottom: Control Assembly
Noise Reduction Antenna Control Board
Noise Reduction Antenna Control Board
and Ferrite Rod Tuning Coil
Antenna
Assembly
An external PVC tube covers
the foil covered ferrite rod (not
shown for simplicity)
Aluminum Foil Covering
Antenna Board
Reduction Noise Antenna Testing
Noise Reduction Antenna Testing
PVC Antenna
Assembly
Spectogram Analysis of Windom Antenna Signal
Level S10
Signal
level
S10 S10
Signal
Level
Time
Spectogram Analysis of Random Coil
Antenna Signal Level S8
Signal Level S8
Time
Spectogram Analysis of Ramsey Magnet
Antenna Signal Level S7
Signal Level S7
Time
Useful Links
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http://www.ipass.net/teara/brew.html QRP Homebuilder’s Page
http://www.ramseyelectronics.com/ Ramsey QRP kits etc.
http://www.fix.net/~jparker/wilderness/sst.htm Wilderness Radio Trans.
http://www.elecraft.com/KX1/KX1.htm
Elecraft KX-1 Transceiver Kit
http://www.qsl.net/ve6bpr/
Amateur Radio Wireless Comm.
http://home.alltel.net/johnshan/qrp_ss_freqs.html
K3WWP’s Home Page
http://www.arrl.org/tis/info/qrphome.html
ARRL Low Power Operating
http://mailman.qth.net/mailman/listinfo/qrp-l/ Subscribe to QRP-L mail list
http://home.alphalink.com.au/~parkerp/qrp/frequencies.htm Australian QRP
HomePage
http://www.amazon.com/ History of QRP in the U.S., 1924-1960 (Paperback) by Adrian
Weiss (Author)
•
•
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•
http://www.amazon.com/ QRP Power: The Best Recent Qrp Articles from QST, QEX
and the ARRLHandbook (Paperback) by Joel Kleinman (Editor), Zack Lau (Editor)
http://www.qrp4u.de/index_en.html
The DL2YEO homepage
http://www.amqrp.org/
American QRP Club
http://www.njqrp.org/
New Jersey QRP Club
http://www.fix.net/~jparker/wild.html
Wilderness Radio
http://www.qsl.net/miqrpclub/
Michigan QRP Club
http://www.qrpworld.com/
QRP World.com
http://www.netwalk.com/%7Efsv/CWguide.htm A Beginner’s Guide to Making
CW Contacts
http://home.c2i.net/hamradio/anifram.html
Clip Art
Ham Radio Animation
73’s
KC9JPZ