SKCC 5123T----- FISTS 14979----- Flying Pigs 2331----- NAQCC 3610-----QRP ARCI 14176-----Polar Bear 257

Sunday, July 20, 2014

RaDAR Contest Antennas: Many Choices!

Rapid Deployment Amateur Radio contests have many choices: bands, radios, antennas and locations among them. As for bands I focus on 40, 20, 15, 10 and 2 meter FM simplex. The antennas I have chosen in previous RaDAR contests are as follows:

April 2013
40 Meters: 88 foot Norcal Doublet
20, 15 meters: Alexloop

Nov 2013
40 Meters: 66 foot End Fed Half Wave
20 meters: 33 foot End Fed Half Wave

April 2014
40, 20, 15 and 10 meters Alexloop

In April 2014, I went with the Alexloop exclusively. I only had one local 40 meter contact with it. I lost a good part of the first hour trying for more. So I will go with something more substantial on 40 meters. I have experimented with 100 and 50 foot wires using a 9 to 1 Unun in the time since the April contest. I am leaning toward using the 100 foot wire as an inverted L to start off with. The L will have a 30 foot vertical component and a 70 foot horizontal component. With 70 feet in the horizontal I suspect it will handle NVIS nicely. In fact, I had the most glowing QRP report ever with that antenna on 40. Now the higher bands could be handled by the Alexloop or a 50 foot inverted L perhaps. Certainly the Alexloop has the least setup time. So more to ponder before the July 26th RaDAR contest. Watch out I have so many choices it is easy to change my mind.

Good Luck on the July 26th RaDAR Contest!

88 foot Norcal Doublet

33 foot end fed half wave for 20 meters


100 foot end fed wire

Wednesday, July 16, 2014

The Summer RaDAR-Contest is July 26th

The Summer (Northern Hemisphere) Rapid Deployment Amateur Radio (RaDAR)-America Contest is hereby announced - due to popular request - for July 26th, 2014 starting at 14:00 UTC and ending at 18:00 UTC. Canadian and Northern USA hams can take advantage of their summer weather. All hams in any locations are welcome to participate. Be safe!

All rules from prior announcement apply as posted at this link.

I will be challenged by the summer heat here in Florida, but I plan to participate. I may dial it back to fixed portable or moving by vehicle rather than pedestrian mobile. The planning is a fun part of the RaDAR experience. There also will be RaDAR contests in November and October. Those are great weather dates here in Northwest Florida.

RaDAR originated in South Africa headed up by Eddie ZS6BNE. It has spread to the Americas with the efforts of Marcus NX5MK. There is a growing worldwide participation. Please visit the RaDAR Community on Google+.

Sunday, July 6, 2014

My Perspective on Array Of Light

I have been doing more reading than operating recently. I have spent a week reading Array of Light by Tom Schiller N6BT. This book is unique in correlating on-air performance with the efficiency and design of antennas. Tom does say any antenna will work but endeavors to explain how a few db can make a difference in performance and enjoyment. I recommend the book. Bear in mind much of the book is devoted to yagis. many of us are not going to have one. However, the best part of the book for me is the discussion of verticals used near or over saltwater. Tom says a vertical in that situation can be better than a yagi.

The shocking thing for me is I was ready to conclude that the antenna and efficiency is not as important as some say. In other words my rate of QSOs does not seems to increase dramatically with one antenna or another or even power level. Bear in mind most of my operation is portable and my goal is just to make some QSOs. The rate of QSOs seem constant at four or five an hour. I will ragchew any chance I get. The QSO rate can be higher and it just depends on whether there are other stations out there who want to work me. For example, my best rate of QSO was 13 per hour when I operated the Peanut Sprint at one watt. There were many Georgia stations there ready to work me. So I was ready to say opportunity and conditions are significant drivers and ultimately the operator is probably the most important factor. I have heard of  DXCC holders that did it with QRP and even with attic antennas.

Now perhaps I have been already following some Tom's advice on antennas as my wire antennas tend to be long relative to wavelength and somewhat high. I also get them in the clear and often near saltwater. The smoking gun for me is my use of  28 gauge ribbon cable with two conductors in parallel. There is loss in the resistance there but does not seem to bite me too bad. That ribbon cable is so convenient and easy to deploy. I also use tuners and baluns I can't say what the loss they have.

I think there is a mental factor to portable antennas. I started out thinking the Alexloop could not be a serious antenna. I eventually got past my mental handicap and enjoy that antenna immensely . I am blown away with 40 meter QSOs on the Alexloop where it is 15% efficient. I say be careful not to get "Blinded by Science." I will admit that I benefit often by the other station having a killer antenna. However, it seems I end up also working stations with antennas in the attic. So go figure.

Fortunately, there is lots of fun to be had operating portable with antennas that are less efficient than a dipole or a yagi. I don't think this necessarily disputes Tom's argument on efficiency. Perhaps I will use that dipole with 14 gauge wire and low loss feedline more often. It just takes three supports to do it, I usually get away one or two supports or just a tripod with the Alexloop.

Tom has definitely convinced me to do more with verticals near salt water. I think I will try resonant verticals near saltwater with gull wing radials. I have access to state parks on the Gulf Coast of Florida and that is just too much of an opportunity to pass up. I have enjoyed and learned much from Array of Light. Thanks for a great book Tom.

Greg N4KGL

Sunday, June 29, 2014

2014 ARRL Field Day Ops with Panama City ARC

My Field Day was short and sweet.  I was on the site with the Panama City ARC using call W4RYZ about ten hours and operated about nine. Since last year I have put together a 100 watt go box based on the Icom 7100 and a 30 ah LiFePO4 battery. To complete the set is a SGC 237 tuner and a 100 watt solar panel.  This year I decided do a 100 foot doublet with the SGC 237 at the center. The SGC was at the top of  camo poles off a hitch mount on the truck. The ends were supported by 31 foot jackite poles. The ground was hard so we drove in a length of angle iron with a sledge hammer and strapped the poles to them. The antenna was maybe 27 feet up with a little sag. My fellow club member Phil N4STC helped set this up, did logging and got in some operating on the rig.

The SGC needs 12 volts and being at the top of a pole I had planned to use MFJ Bias Tees but they failed on me in a pre field day checkout. Not having time to mess with them I used a 3AH battery strapped to the pole. It worked but would be a pain to change out. the SGC seems draw about 250 ma steady for the relays. I had a 70 foot run of coax from the tuner to the operating table. We we able to take advantage of some shade and avoided using a pop-up canopy. The weather was hot but comfortable in the shade.

The 100 watt solar panel was in the sun and with a LiFePO4 controller it fed the battery. The sun was blocked by clouds early but had a good run of sunshine for most of the time. I had some meters on the controller and out of the battery to the rig. The charge was about 1.25 ah per hour and that was just what we were using to the rig running at 80 watts. Our contacts were hunt and ponce so the duty cycle was not all that high. The bottom line is we were running solar while the sun was shining.

The 100 foot doublet was just the ticket. We did well on 20 meters and best on 40 meters. We were able to snag the Virgin Islands and Puerto Rico on 15 meters which was otherwise dead. We also picked up 80 meter contacts after dark.

I can say I am ready for the next Field Day class event at the higher power. I would go with the 100 foot doublet again. Last year we operated the KX3 at 10 watts for the whole duration off a 15 AH battery so that is a good way to go as well. You just have to work a bit harder for those contacts. At 80 watts almost every one we heard came back to us and only had to give up on a few big pile ups. I still want to do a QRP entry someday. Marv KK4DKT had the other rig on the site. He brought a nice travel trailer and enjoyed the air conditioning. He did well making digital contacts.

100 foot doublet with the SGC 237 at the center

camo poles off the hitch mount.

31 foot jackite pole holding up one end of the doublet

100 watt solar panel

Icom 7100 setup

Phil N4STC operating after dark

Monday, June 16, 2014

Solar Power for N4KGL 100 watt Portable Go Box

My first solar panel was a non foldable panel of roughly 1 by 4 feet that was rated at 15 watts. I find now that there are foldable 100 watt panels at a good price point. I am using a Chinese Windcong solar controller compatible with LiFePO4 batteries instead of the supplier controller.. Initial tests look good. The controller will throw around 4.5 amps into the battery and shut-off about 13.7 volts. I kind of like that. I have hooked the controller to the battery hard wired. The controller voltage will clamp down to the battery voltage. You do not want the controller to hook directly to the rig as you could exceed the rated voltage of the rig. 

My 100 watt Portable Go Box is based on the Icom 7100 and has a 30 ah LiFePO4 battery. So this is NOT a solar panel for RaDAR pedestrian mobile. But could be handy for a field day base camp. 

testing with 10 ah battery

100 watt Portable Go Box

Tuesday, June 3, 2014

A Merry Month Of May for Outdoor Operating

May was an excellent month for operating outdoors for N4KGL in Northwest Florida. One week was rained out but the others were fine for operating. My wife Linda worked out of town on three Saturdays. So I drove and operated while she worked. I find the State Parks here are excellent and offer saltwater sites on the gulf and the bay sides. I experimented with 100 foot wires end fed and in loop configurations. You will see my notes below.

Outing 1: May 3rd St. Andrews park 22 contacts

end fed 100 foot wire with 9 to 1 unun including counterpoise
sloping up to 31 foot pole at the center and the end at 20 foot high. I was pleased with 20, 17, 15 12 and 10 meter contacts.

Outing 2 :May 17th St. George Island 18 contacts

Antenna 1: end fed 100 foot wire with 9 to 1 unun including counterpoise
sloping up to 31 foot pole at the center and the end at 20 foot high  I had good luck on 40, 17 15 and 10 meters.

Antenna 2: delta loop from 100 foot wire fet at the corner with SGC 237 tuner. I had a tough time on 17 meters SSB even though I was running between 40 and 80 watts. 20 and 10 meters were better. I did work ZL1DK on 10 meters.

Outing 3: May 24 St George Island 34 contacts

Antenna 1: 88 foot doublet - a outstanding  job on 40 meter NVIS

Antenna 2: vertical delta loop 100 foot wire fed center bottom with SGC 237 tuner

Outing 4: May 26 Columbus Georgia backyard  12 Contacts

Antenna: Irregular loop from 100 foot wire fed with SGC 237 Tuner. QSOs on 80, 40, 30, 20, 17 & 15. I was very pleased with this configuration.

Outing 5: May 31st Gulf County Florida Parks 17 contacts

Antenna 1: end fed 100 foot wire with 9 to 1 balun and no counterpoise
the first 31 foot of wire vertical and remainder sloping to 20 foot pole. Outstanding report from Lake City FL station on 40 meters. 40, 17 15 and 10 meter contacts

Antenna 2: Alexloop - Nice 40 meter NVIS contact to Tallahassee FL. Also a nice 17 meter contact with VE4AKI 10 watts both ways.

I should mention that the KX3 is going a great job. I hope I don't suffer a penalty for being so close to the saltwater. Note the sun beating down on the rig and on some long transmissions the PA can get into the 50s degree C. Once it went over temp. This is manageable problem just something to watch. I think a small sun shield might be good. I also may use a small fan. I don't want to change the pack-up size of the KX3 by adding fins. I also used the Icom 7100 on one outing. I can't say the extra power is any magic bullet. But it is one more option I have.

Greg N4KGL

Sunday, June 1, 2014

N4KGL RaDAR Adventure in Gulf County Florida

My Rapid Deployment Amateur Radio (RaDAR) adventure this time was to the Port St Joe / Cape San Blas area in Gulf County, Florida. I initially identified five sites that were near the water. I was going to do all five in eight hours to test my re-deployment skills. I chickened out and did just three. 

I spent the most time at Eagle Harbor area at the Cape San Blas State Park. I sat within a few feet on water. It kept rising and I had to scoot back. My first QSO was K4ARQ in Tallahassee. That was good NVIS on the Alexloop. Then I switched to a 100 foot wire fed with 9 to 1 unun. I worked VA, FL and GA on SSB. I got a glowing report from KB8OTM in Lake City FL. Then I switched to 17 SSB and still on the 100 foot wire. I got MI, FL and IN. The Florida contact was Bob KK4DIV from 45 miles away in Panama City. He was weak but got that he was 5 watts portable. That is quite a close in contact for 17 meters. Next was LY1G Lithuania on 17 CW. I had a good run on W1AW special event stations. I got W1AW/7 Wyoming on 17 SSB and 15 SSB. Then I got W1AW/0 MO on 10 SSB and 10 CW. 

I returned to the Alexloop and worked KF5RAU. He was running a 1/2 watt on a Rockmite. Awesome! I also worked KC9WY0/0 who had a 11 year old CW operator doing a great job. I decided to go to the beachside of the park with Alexloop. I worked VE4AKI in Manitoba on 17 meter SSB. We both were 10 watts. I also checked into the OMIS net with KK5EDD in OK as net control on 20 SSB. I got a sprinkle of rain and packed it up. It threatened rain all day but we had very little. Time was getting short and I drove back to Port St Joe area to Jetty Park. I got one last QSO. It was AF5U in Dallas, TX. 

A great day and not overly hot. There was pretty good crowd taking advantage of the water at all three sites. Florida in May is hard to beat!

Eagle Harbor at the State Park. The wind was kicking up some waves.

The Gulf Side of the State Park

Jetty Park in Port St Joe

My favorite picture of Eagle Harbor when the winds died down. Great Colors.

A bird at Jetty Park