Presentation on theme: "QRP and Home Brews presentation at the 2008 W. V. A. R. A"— Presentation transcript:
1QRP and Home Brews presentation at the 2008 W. V. A. R. A QRP and Home Brews presentation at the W.V.A.R.A. HAMFEST March 8, 2008John SwezKC9JPZURL for download of this Presentationnewton.indstate.edu/swez
2This talk consists of four parts An introduction to QRPAn introduction to the speakerThe RAMSEY 40 meter low power kit and testingSmall Magnet Noise Reduction Antenna and testing
3January 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 WA0ZZGTo be classified as QRP your power level must not exceed 5 watts output when transmitting a CW signal.
4“Borrowed From” New Jersey QRP Club http://www.njqrp.org/whyqrp/2.htm
5One of the first Commandments of QRPing K.I.S.S. Use a simple dipole up in the treeReference: Same article as previous slideLook! 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
6Another 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 -
7"What motivates the low-power (QRP) amateur operator "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.From VE6BPR’s Home Page About QRPer’s
8“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!
9Hallicrafters SX-28A Super Skyrider My rig in 1954Heathkit DX-35ARRL Field Day circa 195?W3HUKW3OAQHallicrafters SX-28A Super Skyrider
10International 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”.
11How 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 In fact,I took my General Class exam at W.V.A.R.A Field Day
12How 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”.
14To See The Enormous Growing Popularity of QRP Go to 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.
16CW vs SSB Graph again courtesy of New Jersey QRP Club and (why QRP?)
17Here’s a nice twist: a tube QRP Rig (glow-bug) W2NTK circuits
18Picture from Ramsey Home Page Ramsey 40 m QRPc RigPicture from Ramsey Home PageManual at:Transistor circuit, oscillator, RF amp chain, and clean keying stageRF output approx 1 Watt (.75W for QRP-20)Pi-network output for good matching and harmonic suppressionProvision for two internal crystals, front panel switchingVCXO tuning, frequency can be tuned approx 7kHz around xtal freq.(3.22 kHz with our rig)
2154.3 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
22V p-p output voltage versus Input voltage to transmitter using 54 V p-p output voltage versus Input voltage to transmitter using 54.3 ohm termination and RG-58c (50 ohm impedance) cable to oscilloscopeRamsey 40 meter QRP rigRF power calculated as V(p-p)2/(8*53.4)From 2007 RF Experimenters HandbookAt V input current drain is 0.34 amps
23FFT Signal Analysis of QRP 40c Ramsey Transmitter using a A-M Systems Model 3800 Digital Oscilloscope with Rectangular MathTwo repeat experiments at Volts input. The rightmost peak represents the 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
24Compliance of the Ramsey QRP 40c Rig with harmonic radiation Solution courtesy of Mathematica 4.0
25Frequency Stability Measurement of QRP 40 Rig 10 k tuning pot = kHz Max CW and Max CCW. Range = kHzInput to QRP RigXtal osc pot at max CW
27Summary of Ramsey QRP 40 Evaluation Maximum Output V (peak-peak) at 14 Volts = 16.2 VMaximum Output = 0.6 watts at 14 Volts DC input1Harmonic Output Crude Method: Relative signal strength (S meter reading) S6 at kc (QRN bg = S3) with Harmonic #1 at 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 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
28Ramsey Electronics SM100 Signal Magnet Noise Reduction Antenna Tunes entire AM broadcast band and can be configured 500 kHz to 15 MhzFaraday Shield eliminates electrostatic noiseVaractor diode tuning – one wire connection 500’Low noise high gain FET preamplifier circuitRugged antenna enclosure constructed from PVC pipeDirectional properties of antenna helps to “null” overpowering stations
35Spectogram Analysis of Windom Antenna Signal Level S10 Time
36Spectogram Analysis of Random Coil Antenna Signal Level S8 Time
37Spectogram Analysis of Ramsey Magnet Antenna Signal Level S7 Time
38Useful Links http://www.amqrp.org/ American QRP Club QRP Homebuilder’s PageRamsey QRP kits etc.Wilderness Radio Trans.Elecraft KX-1 Transceiver KitAmateur Radio Wireless Comm.K3WWP’s Home PageARRL Low Power OperatingSubscribe to QRP-L mail listAustralian QRP HomePageHistory of QRP in the U.S., (Paperback) by Adrian Weiss (Author)QRP Power: The Best Recent Qrp Articles from QST, QEX and the ARRLHandbook (Paperback) by Joel Kleinman (Editor), Zack Lau (Editor)The DL2YEO homepageAmerican QRP ClubNew Jersey QRP Club
39KC9JPZ 73’s http://www.fix.net/~jparker/wild.html Wilderness Radio Michigan QRP ClubQRP World.comA Beginner’s Guide to Making CW ContactsHam Radio Animation Clip Art73’sKC9JPZ