QRP Presentation at HRUQRP Presentation at HRUJohn Meade W2XSJohn Meade W2XS

••Contact Info:Contact Info:––jm416@optonline.netjm416@optonline.net––JJohn.meade@ncc.eduohn.meade@ncc.edu

QRP Presentation at HRUQRP Presentation at HRUJohn Meade W2XSJohn Meade W2XS

•• TopicsTopics–– Philosophy of QRPPhilosophy of QRP–– EquipmentEquipment–– AntennasAntennas–– My QRP Rig History in PicturesMy QRP Rig History in Pictures

QRP PhilosophyQRP Philosophy

•• Operating at 1 to 5 watts can be fun and Operating at 1 to 5 watts can be fun and addictive.addictive.

•• The results are surprising when the band The results are surprising when the band is open.is open.

•• QRP does not necessarily have to QRP does not necessarily have to ““replacereplace”” QRO. Do both!QRO. Do both!

•• Operate from the back yard or a park Operate from the back yard or a park bench.bench.

QRP PhilosophyQRP PhilosophyLook at how much fun ILook at how much fun I’’m having!m having!

QRPQRPPhilosophyPhilosophy

•• Even simple QRP rigs will provide fun and Even simple QRP rigs will provide fun and satisfaction.satisfaction.

•• The lower the current drain, the longer The lower the current drain, the longer the batteries will last.the batteries will last.

•• Many QRP rigs are simple but high Many QRP rigs are simple but high performance.performance.

•• Put up the best antenna possible.Put up the best antenna possible.

QRP EquipmentQRP Equipment

•• SpecificationsSpecifications–– Bands covered Bands covered –– mono or multimono or multi–– Power Output Power Output -- fixed or variablefixed or variable–– Selectivity Selectivity –– fixed or variablefixed or variable–– Sensitivity Sensitivity –– most are most are ““good enoughgood enough””–– Stability Stability –– drift is annoyingdrift is annoying

QRP Equipment QRP Equipment -- BandsBands

•• 40m and 30m are popular QRP bands.40m and 30m are popular QRP bands.•• 20 thru 10 are great QRP bands when 20 thru 10 are great QRP bands when

openopen•• II’’ve had good results on 80m toove had good results on 80m too•• Some people operate QRP on 160mSome people operate QRP on 160m•• Antennas might be an issue on 80 and Antennas might be an issue on 80 and

160160

QRP Equipment QRP Equipment -- PowerPower

•• 2W or 3W is fine for a QRP rig.2W or 3W is fine for a QRP rig.•• A 2x increase in power is only 3 dB which A 2x increase in power is only 3 dB which

is barely noticeable.is barely noticeable.•• A 10x increase in power is 10 dB which is A 10x increase in power is 10 dB which is

only 2 only 2 ““SS”” units.units.•• Receiver current drain is important when Receiver current drain is important when

using batteries.using batteries.

QRP Equipment QRP Equipment –– Receive PowerReceive Power

•• The K2 has a 2.9 AH battery and draws The K2 has a 2.9 AH battery and draws 200 mA in receive200 mA in receive–– ThatThat’’s 14.5 hourss 14.5 hours

•• The SST draws 15 mA and I have a 2.0 The SST draws 15 mA and I have a 2.0 AH batteryAH battery–– ThatThat’’s 133 hourss 133 hours

QRP Equipment QRP Equipment -- PowerPower•• RF Output Power vs. DC Input PowerRF Output Power vs. DC Input Power•• Typical Rig on Transmit:Typical Rig on Transmit:

–– Out = 100WOut = 100W–– In = 14V x 20A = 280WIn = 14V x 20A = 280W–– 36% Efficiency36% Efficiency

•• Typical QRP Rig on Transmit (K1):Typical QRP Rig on Transmit (K1):–– Out = 5WOut = 5W–– In = 14V x 800 mA = 11.2WIn = 14V x 800 mA = 11.2W–– 45% Efficiency45% Efficiency

•• Operating a 100W rig at 5W may be Operating a 100W rig at 5W may be 10% efficient10% efficient

QRP Equipment QRP Equipment -- SelectivitySelectivity

•• Many QRP rigs have sharp but fixed filters.Many QRP rigs have sharp but fixed filters.•• I like to use the widest bandwidth possible I like to use the widest bandwidth possible

and make it narrower as needed.and make it narrower as needed.•• Some filters are variable.Some filters are variable.

QRP Equipment QRP Equipment -- SensitivitySensitivity

•• RF and IF amplifiers are not really needed.RF and IF amplifiers are not really needed.•• Many rigs use just the NE602Many rigs use just the NE602--LM386 ICs.LM386 ICs.

–– SST, SWL40+, KX1, K1SST, SWL40+, KX1, K1

•• Headphone volume is ample enough.Headphone volume is ample enough.•• External audio amplifiers can be used.External audio amplifiers can be used.

QRP Equipment QRP Equipment –– The SSTThe SST

QRP Equipment QRP Equipment -- StabilityStability•• The simplest rigs are The simplest rigs are xtalxtal controlled.controlled.•• Some have a VCXO. Some have a VCXO. •• Some have tuning capacitorsSome have tuning capacitors

–– OHR400 OHR400 –– a bit driftya bit drifty•• Many have Many have varactorvaractor diodes for tuning.diodes for tuning.

–– SWL40+ = 70 kHzSWL40+ = 70 kHz–– SST40 = 15 kHz (2 ranges)SST40 = 15 kHz (2 ranges)–– OHR100A = 70 kHzOHR100A = 70 kHz–– A 10A 10--turn pot can be installed turn pot can be installed –– I use I use

““KnobpotsKnobpots”” on many QRP rigs:on many QRP rigs:

This was the calibration chart for This was the calibration chart for my OHR100A with the 10my OHR100A with the 10--turn turn

KnobpotKnobpotOHR100AOHR100A

KnobKnob FreqFreq

0.00.0 7003.67003.6

1.01.0 7007.27007.2

2.02.0 7013.17013.1

3.03.0 7020.77020.7

4.04.0 7029.67029.6

5.05.0 7039.47039.4

6.06.0 7048.97048.9

7.07.0 7058.37058.3

8.08.0 7066.87066.8

9.09.0 7074.77074.7

10.010.0 7081.87081.8

SW40 in an old case from workSW40 in an old case from work

MFJ Cub (for 15 meters)MFJ Cub (for 15 meters)

QRP Equipment QRP Equipment -- StabilityStability•• Some are synthesized for rockSome are synthesized for rock--solid solid

stability:stability:–– Elecraft KX1 and K2Elecraft KX1 and K2–– Ten TecTen Tec’’s new 40/20 or 40/30 (HB1A s new 40/20 or 40/30 (HB1A

copies)copies)

My Favorite QRP PaddlesMy Favorite QRP Paddles

•• PaddlettePaddlette Model PKModel PK--11–– No vertical arm movement (which is good)No vertical arm movement (which is good)

•• Black Widow Black Widow –– a kita kit•• Scorpion Scorpion –– also a kitalso a kit•• K9LU Bulldog K9LU Bulldog –– made from a paper clipmade from a paper clip

Simple! But it works!Simple! But it works!

The KX1 Paddle was a bit hard to The KX1 Paddle was a bit hard to get used toget used to

QRP AntennasQRP Antennas

•• A good antenna system has both of these A good antenna system has both of these qualities:qualities:–– The transmitterThe transmitter’’s impedance should be matched to s impedance should be matched to

that of the antenna.that of the antenna.–– As much signal as possible should radiate from the As much signal as possible should radiate from the

antenna (preferably in the desired direction).antenna (preferably in the desired direction).

•• These depend on the type and length of the These depend on the type and length of the antenna and the frequency of operation.antenna and the frequency of operation.

QRP AntennasQRP Antennas

•• Laws of PhysicsLaws of Physics–– We are trying to radiate a radio waveWe are trying to radiate a radio wave–– The length of the wave depends on the The length of the wave depends on the

frequency:frequency:•• A Frequency of 7 MHz is a Wavelength of 40 A Frequency of 7 MHz is a Wavelength of 40

metersmeters•• Half wave means 20 meters = 66 feetHalf wave means 20 meters = 66 feet

–– A typical basic antenna is a halfA typical basic antenna is a half--wave dipole.wave dipole.

QRP AntennasQRP Antennas

•• Laws of Physics (cont)Laws of Physics (cont)–– In order to radiate, a In order to radiate, a ““standing wavestanding wave”” is is

needed on the antenna.needed on the antenna.–– A standing wave should not be present on the A standing wave should not be present on the

transmission line.transmission line.–– If the antenna is too short, then the standing If the antenna is too short, then the standing

wave will form on the antenna AND the wave will form on the antenna AND the transmission line AND the tuner transmission line AND the tuner –– resulting in resulting in a poorly radiated signal.a poorly radiated signal.

QRP AntennasQRP Antennas

•• Universal antenna properties:Universal antenna properties:–– Radiation resistanceRadiation resistance–– Loss ResistanceLoss Resistance–– Feed point impedanceFeed point impedance–– Dependence on groundDependence on ground–– Radiation patternRadiation pattern–– GainGain–– EfficiencyEfficiency

QRPAntennasQRPAntennas

•• Popular Antenna Types:Popular Antenna Types:–– DipoleDipole–– LoopLoop–– VerticalVertical–– Random WireRandom Wire–– Beam (Beam (YagiYagi))–– QuadQuad

•• The following pages may give you some ideas The following pages may give you some ideas for an antenna that actually works well.for an antenna that actually works well.

Portable 40m to 10m Inverted V Portable 40m to 10m Inverted V Antenna used by W2XS Antenna used by W2XS

•• JackiteJackite 3131--foot pole and ground mount (or, foot pole and ground mount (or, bungeebungee--cord it to a table or deck railing).cord it to a table or deck railing).

•• Coleman camping reel. Coleman camping reel. Buy 4 of them. Buy 4 of them. Use two Use two for the antenna wire (I use 33 feet on each side for the antenna wire (I use 33 feet on each side but you can 22 feet and above for 40m to but you can 22 feet and above for 40m to 10m). 10m). Use the other two as ropes to secure the Use the other two as ropes to secure the antenna ends to the ground stakes. antenna ends to the ground stakes. WalmartWalmart, , etc., sells these things.etc., sells these things.

•• Two tent stakes to secure the rope ends. Two tent stakes to secure the rope ends.

Portable 40m to 10m Inverted V Portable 40m to 10m Inverted V Antenna used by W2XS Antenna used by W2XS

•• 300300--ohm twin lead for the feed line. ohm twin lead for the feed line. I bought I bought 50 feet from Radio Shack. 50 feet from Radio Shack.

•• I use a small piece of Plexiglas for the center I use a small piece of Plexiglas for the center insulator with a small hole drilled in it. insulator with a small hole drilled in it. I use a I use a twisttwist--tie to secure it to the ring on the top tie to secure it to the ring on the top section of the pole. I have also used a small PVC section of the pole. I have also used a small PVC pipe coupling section from the local hardware pipe coupling section from the local hardware store. store.

•• Pole mounting: The Earthworm. Pole mounting: The Earthworm. JackiteJackite sells a sells a mount also.mount also.

•• BLT Tuner (or equivalent set up. BLT Tuner (or equivalent set up. I use the K2 I use the K2 internal tuner and a BL1 balun).internal tuner and a BL1 balun).

QRP AntennasQRP Antennas

QRP AntennasQRP Antennas

QRP AntennasQRP Antennas

QRP AntennasQRP Antennas

QRP AntennasQRP Antennas

QRP AntennasQRP Antennas

QRP AntennasQRP Antennas

QRP AntennasQRP Antennas

The other question deals with feedline lengths. Is there any 'ideal' length? Yes and no. Some feedline lengths will present an extremely high impedance to the tuner on certain bands. Each installation is different, but here are some rough guidelines that may help:Start by trying a feedline listed in the lengths below. It may take some trimming or adding of feedline to work well on the range of bands you want to cover. The worst possible feedline lengths are shown in brackets: If Ant is 120 ft per leg it will cover 160 thru 10 meters. Feedline of 40-70 or 150- 190 feet suggested. [Avoid lines around 120 or 240 ft] If Ant is 65 ft per leg it will cover 80 thru 10 meters. Feedline of 25-40, 80-100 or 140-160 feet suggested. [Avoid lines around 60, 120, or 180 ft] If Ant is 33 ft per leg it will cover 40 thru 10 meters. Feedline of 40-50, 70-80, 100-110 or 130-140 feet suggested. [Avoid 30, 60, 90, 120 ft]

AA1DO Condo Ant (275AA1DO Condo Ant (275’’ OCF)OCF)

AA1DO Condo Ant (275AA1DO Condo Ant (275’’ OCF)OCF)

AA1DO Condo Ant (275AA1DO Condo Ant (275’’ OCF)OCF)

AA1DO Condo Ant (275AA1DO Condo Ant (275’’ OCF)OCF)

•• One end 200One end 200’’ longlong•• The other is 75The other is 75’’ longlong•• One end is 8One end is 8’’ off the ground at the endoff the ground at the end•• Author claims 160m to 10mAuthor claims 160m to 10m•• http://www.aa1do.com/hamcondo.htmhttp://www.aa1do.com/hamcondo.htm

22--el 10el 10--m Beamm Beam

W4RNL W4RNL –– 4444’’ AntennaAntennaUse with a balanced tuner from Use with a balanced tuner from

40m to 10m40m to 10m

Attic trap Dipole (NU3E)Attic trap Dipole (NU3E)http://http://www.nerc.com/~jdegood/coaxtrapwww.nerc.com/~jdegood/coaxtrap//

Half SquareHalf Square Freq. MHz

C pF L uH

1.85 160 46.33.50 80 25.83.50 86.9 23.83.65 80 23.83.80 73.7 23.83.80 80 21.97.00 40 12.910.1 30 8.2814.0 20 6.46

http://www.angelfire.com/md/k3ky/page38.html

Hex BEAMHex BEAM

1. The HEX has a very small wingspan, BUT....NO LOADING COILS OR TRAPS!! (Therefore it does not have the losses associated with such devices)

2. It appears to perform much as a full size 2 element yagi, but with a better match to 50 Ohm coax, comparable gain and f/b, but with a bit less bandwidth

3. Physically, it is very light and strong. It can be multibanded by nesting elements one inside the other, like a multi-band Quad.

4. As it is hexagonal in shape, it has no "bias" in windy conditions, so a very small rotator is sufficient.

5. http://ireland.iol.ie/~bravo/ahexbeam.htm

160160--m Inverted m Inverted ““UU”” (K3MT)(K3MT)

66--Band Windom (K3MT)Band Windom (K3MT)

Magnetic Loop (W2BR)Magnetic Loop (W2BR)http://www.standpipe.com/w2bri/build.htmhttp://www.standpipe.com/w2bri/build.htm

65% Efficiency65% Efficiency

22--Band HalfBand Half--Wave Wire TunerWave Wire Tuner

““ZZ”” Match TunerMatch Tuner

W5JHW5JH

W5JHW5JH

Another Another ½½ Wave TunerWave Tuner

The Tuning capacitor in the AMU can be a 365 - 500pF broadcast type or a miniature version is OK for QRP use. Counterpoise lengths

•3.5 & 7.0Mhz - 17ft •14Mhz - 6.5ft •28Mhz - none

Tuning UnitValues for coils in the unit, based on a 2 inch former and 16 swg wire:

•3.5Mhz 21 turns •7.0Mhz 7 turns •14.0Mhz - 5 turns.

My First QRP Rig was the My First QRP Rig was the HeathkitHeathkit HW8HW8Direct Conversion means you hear signals on both Direct Conversion means you hear signals on both

sides of zero beatsides of zero beat

Upper left = Upper left = NorCalNorCal NCNC--40A40ALower left = Ten Tec Argosy Lower left = Ten Tec Argosy –– 5 or 50 watts5 or 50 watts

Lower left = Elecraft KX1, one of Lower left = Elecraft KX1, one of my all time favorite QRP rigsmy all time favorite QRP rigs

I sold the Argosy to buy the I sold the Argosy to buy the Elecraft K2Elecraft K2

I sold the KX1 to help fund the I sold the KX1 to help fund the purchase of the K3.purchase of the K3.

I sold the TSI sold the TS--930 and a few boat 930 and a few boat anchors to help fund the purchase of anchors to help fund the purchase of

the P3the P3

Ten Tec Argonaut Ten Tec Argonaut –– Model 515Model 515Was Good in its TimeWas Good in its Time

Portable QRP CasePortable QRP CaseEverything That You Need!Everything That You Need!

A Few Of My QRP RigsA Few Of My QRP Rigs

80m Beam 80m Beam –– Dream on!Dream on!

This takes 100W to operate! State This takes 100W to operate! State of the art in 1955.of the art in 1955.

State of the Art QRP State of the Art QRP –– 19801980’’ss

The K2The K2Need just a paddle and an antennaNeed just a paddle and an antenna

The KX3The KX3A Great New QRP RigA Great New QRP RigMany BuiltMany Built--In FeaturesIn Features

My RecommendationsMy Recommendations

W2XSW2XS

Rig (kit)Rig (kit)

•• QRP Kits PFR3 ($250) 5W+QRP Kits PFR3 ($250) 5W+•• OHR 100A ($150) 5W+OHR 100A ($150) 5W+•• Elecraft K1 ($300 to $400+) 5W+Elecraft K1 ($300 to $400+) 5W+•• Elecraft KX1 ($300 to $400+) 3WElecraft KX1 ($300 to $400+) 3W•• Elecraft K2 ($600+) 10W+Elecraft K2 ($600+) 10W+•• Elecraft KX3 ($1000+) 10W+Elecraft KX3 ($1000+) 10W+

–– Look at Look at eBay.comeBay.com or or eHam.neteHam.net–– Good QRP link: Good QRP link:

http://http://www.amqrp.org/misc/links.htmlwww.amqrp.org/misc/links.html

AntennaAntenna

•• 40 meter dipole fed with old40 meter dipole fed with old--fashioned fashioned twinleadtwinlead on a 31on a 31--foot foot JackiteJackite pole.pole.–– Use the Use the JackiteJackite ground mount.ground mount.–– A tuner is needed but all bands are A tuner is needed but all bands are

covered.covered.

•• PAR Electronics endPAR Electronics end--fed halffed half--wave wave 40/20/10 coax40/20/10 coax--fed antenna.fed antenna.

SummarySummary

•• DonDon’’t skimp on the antenna. Let t skimp on the antenna. Let the entire wave get radiated.the entire wave get radiated.

•• Choose a CW or an SSB rig. Used Choose a CW or an SSB rig. Used rigs are available and sometimes a rigs are available and sometimes a good deal can be found.good deal can be found.

•• Have fun. ThatHave fun. That’’s what this hobby s what this hobby is all about.is all about.