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

Wednesday, April 23, 2014

The Icom 7100 On The Go

I have an Icom IC 7100 as my base rig. However being such a fan of Rapid Deployment Amateur Radio (RaDAR) I can't resist setting it up in a Go Box configuration. Basically I am just packing the gear into a toolbox. I can have the main unit and the battery in the box and the control head on my table.

My battery is a Bioenno LiFePO4 15 amp hour battery. This battery sustained the KX3 at 10 watts for the entire Field Day last year. The Icom 7100 presents some additional challenges for battery operation. It does not seem as battery friendly. The first issue is the Icom 7100 is specified at 13.8 volts plus or minus 15%. This means the lowest voltage is 11.7 volts. I find that when it drops below 11.7 the rig will abruptly shut down. I guess they did not promise anymore than that. It is pretty easy for this to happen due to the voltage drop due to the internal resistance of the battery. I estimate the internal resistance of this particular battery is about .12 ohms. A 10 amp draw could drop the voltage 1.2 volts. This combined with losses in wiring gets you in trouble pretty quick. The bottom line is you will get the rig shutting down even through you have lots of energy left in the battery.

There is something you can do to mitigate this issue. Enter the N8XJK Boost Regulator. I have one in the Go Box. It does what it promises. It will take what ever the battery voltage is and boost it to 14.14 volts open circuit (Adjustable up to 15). Under load it seems to keep the voltage above the 13.8 point.

I think it is fair to say this 15 ah battery may be a little small for this job. It is not sized for the 22 amp draw for a hundred watts. But I am thinking maybe 40 watts SSB and 20 watts CW just to not push it too hard.

Then there is something that was surprising. If you turn the power down to QRP the 7100 is still draw six amps or so. So you won't economize by shifting to QRP. All this makes me appreciate the job Elecraft has done on the KX3. It will reduce the power instead of shutting off. It is also very power efficient. Oh well this makes me think the Elecraft 100 watt amplifier would be something to look at. Then running more than 10 watts portable is questionable anyway for casual operations. However, Field day is coming and I plan to exercise the 7100 at 40 watts and see how it does.

I have some photos from when I took the 7100 Go Box out on my lunch break. I talked to locals Vic K4GXV and Bob WB4BLX via DStar on 2 meters. I did not get around to doing HF. The antenna is a lightweight roll-up slim-jim.

The voltage booster is on the right end of the box.

Slim Jim Antenna.
The battery

The gear packed up

The tool box

Friday, April 18, 2014

N4KGL April 2014 RaDAR Contest Entry

My site for the April 5th RaDAR Contest was Saint Andrews State Park near Panama City Florida. See my log entry below. My strategy was to wear my KX3 and battery and walk with the Alexloop deployed. I call this Semi Pedestrian Mobile. It was threatening rain but the rain never came. First I made five contacts on the beach near the jetties. Then I walked up the beach one kilometer and made five more. Then I headed back to the jetties and went to a gazebo where I could sit. I got five more contacts for a total of fifteen jover the four hour period. I think everyone I passed was just a little interested in what I was doing. Several asked and were very friendly.  I think my choice of the Alexloop paid off. There was less setup time and more time for contacts compared to erecting poles for antennas.

I worked a fellow RaDAR operator Steve KF5RYI  in Texas. The RaDAR Contest was fun and challenging. Speaking of other operators they were global from Fred VE3FAL, Lucy M6ECG to Eddie ZS6BNE and others you can find their stories on the RaDAR Community at this link. The RaDAR America Rules are at this link

Greg N4KGL

Location 1 EM70DD near jetties

Location 2 EM70DD near Sandy Point

Location 3 EM70DC in gazebo near jetties

The view from the gazebo.

Saturday, April 5, 2014

Plan RaDAR, Do RaDAR and Learn from RaDAR

RaDAR is Rapid Deployment Amateur Radio. The first Saturday of April and November is designated for a RaDAR Contest. The contest is four hours.  The focus is on portable operations but with a twist. After five contacts you must travel a specified distance and redeploy. My choice was to redeploy by foot. Operating in this fashion invokes many tradeoffs on your gear and your antennas. If you are like me you will ponder these tradeoffs right up the the start of the contest.

For the RaDAR contest last November, I laid my bets on getting end fed wires as high as possible. I used 31 foot poles and deployed some impressive antennas. I also bought a beach cart to carry my poles and other gear. My site of choice is Saint Andrews State Park. Even though it was a beach cart it became a big chore to cover the required one kilometer distance. This was because nothing rolls that well in loose sand.

So now why not use that Alexloop. That is what I chose for this year. It is definitely easily transported and setup. But why set it up and break it down. That led to what I call Semi Pedestrian Mobile. I just leave the loop setup on a pole and carry the pole. Also I wear the radio and the battery. This eliminates a table and a chair.

There was some drama this year because rain was in the forecast. I got in my mind I should have some back up antennas which I prepared but did not need them. I suspect operating under some cover with the loop is just fine in any case. So it finally came down to the contest day. The beach at the park is beautiful and I like to think being close to the surf invokes the saltwater effect.

In short, I made five contacts near the jetties walked up the beach one kilometer, made five more then headed back to the jetties and went to a gazebo where I could sit. I got five more contacts for a total of fifteen just in time. I think everyone I passed was just a little interested in what I was doing. Several asked and were very friendly. I feared rain but it never came.  I think my choice of the Alexloop paid off. There was less setup time and more time for contacts. My lesson is NEVER DOUBT THE LOOP!

I worked a fellow RaDAR operator Steve KF5RYI  in Texas. Speaking of other operators they were global from Fred VE3FAL, Lucy M6ECG to Eddie ZS6BNE and others you can find their stories on the RaDAR Community at this link.

Greg N4KGL

Sunday, March 30, 2014

RaDAR In the Park

I visited St Andrews State Park near Panama City, FL to do some Rapid Deployment Amateur Radio RaDAR. I guess today was a checkout in anticipation of the RaDAR contest coming up on April 5th.  This was an opportunity to test the KX3 and Alexloop in a Semi Pedestrian Mobile configuration. I call it semi because I only make QSOs at stops when I have the Alexloop planted in the sand. On one side I wear the KX3 in a video case with the top removed,  On the other side is a pack with my 10 AH LiFePO4 battery plus all the miscellaneous items.

I started on the North side of the park at the pier. The skies were clear but the wind was extra chilly about 10 AM. I worked AB5RE in Lubbock TX on 14.060.

I notice the pelicans were cold and hungry. They gathered at the fish cleaning station.

Near the pier is a picnic table. I took advantage of that and worked locals  K4GXV, WB4BLX and N4STC on 146.565 simplex. Then I worked K4GXV, WB4BLX on 18.078 CW. Ron KK4DWE came out to join me. Continuing at the picnic table I got N0KV Ellis County TX on 18.136 SSB. Last contact was IW2HAJ on 28.402 SSB. I was kind of beat up by the cold but Ron inspired me to continue the 1 kilometer walk to Sandy Point.

The walk is next to the Grand Lagoon which has lots of boat traffic and fisherman. The most frequent question was What are you tracking with the loop? I have thought up a good response: Orcas! Seen any?


Greg N4KGL wearing the semi pedestrian mobile pack up. 

At Sandy Point on 17 meters SSB I worked KA2WDV in New York it was a struggle. That was followed by the best contact of the day. It was KB8HHA in Ohio who gave me a solid S9 on his meter and we had a nice chat. I worked locals WB4BLX and K4GXV on two meters and 17 meters SSB from the point as well. I wanted to make use of the leg key while standing and I snagged N7KY in Jackson, TN on 14.055. I did a number of CQs hoping to get some RaDAR buddies but no luck this time.

I'd say the pack up did well for RaDAR. I carried no extras like my table or chair. I hope I am spared the chilly winds and any rain on April 5th!

73s Greg N4KGL

Monday, March 24, 2014

Semi Pedestrian Mobile

Paul W0RW and Ed WA3WSJ are notable /PM operators. They have my respect. I have had the pleasure of working both of them. The fully pedestrian mobile operator can enjoy hiking and operate at the same time. It is quite a trick.

For the Rapid Deployment Amateur Radio (RaDAR) contest I plan to hike but it is not necessary to operate while in motion. I am testing a setup I call Semi Pedestrian Mobile. I carry the rig and battery hooked up on my body. For the antenna I am using the Alexloop. The Alexloop is on a four foot military camo pole. Inside the camo pole is a step in electric fence post. The step in post provides the spike at the bottom of the pole. To operate I just plant the pole and I am ready to operate. To transition I can carry the pole horizontal or put it on my shoulder like a baseball bat. Note that you don't have to stand all the time once the loop is tuned you can sit on the ground or take advantage of a park bench.

The KX3 is in a camera bag wit the top removed on my right side and my 10 AH LiFePO4 battery is in the should pack on my left. A new addition to my gear is an American Morse Miniature Straight Key MS-2. I also got the leg strap for it. The key has a nice feel. The leg strap works and it helps if my truck keys are just below the strap in my pocket.

It is wise to test out this concept before the April 5th RaDAR Contest. I made it to a local park in Lynn Haven Florida. The first round of operation I worked ON4DY Belgium on 21.295, WA7HDI\QRP 21.060 and N5MF on 21.040. Then I ran an errand. On my return, I worked KG4PRK in IA, CT7AEQ in Portugal, and NX1K in WI on 17 meter CW. S57DX Slovenia and N8WGM in OH on 17 meter SSB.

I can receive while I walk via the loop. The park is beside the bay. As I approached the bay I heard a signal get stronger the closer I got to the saltwater. For me this was a verification of the saltwater effect.

Most of my RaDAR buds got snow this weekend. It was in the high seventies here. I am looking forward to the April 5th RaDAR contest. I hope the snow and ice is gone by then and we will have world wide participation.

For the RaDAR Contest details see  IARU Region 1 and for the Americas.

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 with the RaDAR Community on Google+ See

Thursday, March 13, 2014

April 5th Rapid Deployment Amateur Radio Contest

Are you ready for a exciting amateur radio challenge? Deploy as a portable station make five contacts walk one kilometer deploy again and make five contacts. Continue for the four hour period. You could do the same moving three kilometers via car, motorcycle, bicycle or other vehicle. You have entered the world of Rapid Deployment Amateur Radio aka RaDAR. You will enjoy making tradeoffs in radio, antennas, and choice of operating frequencies. The four hour period puts you under a little stress to manage all the factors in real time. Hams worldwide practice RaDAR any time they can but there is the four hour RaDAR contest the first Saturday of April and November. The next RaDAR Contest is April 5th 1400 UTC to 1800 UTC.

In addition to on foot and vehicle categories, there are also portable and at home categories. Each category has a multiplier. Power is your choice QRP and up with multipliers. All amateur bands, besides the WARC bands, are allowed including cross band contacts via amateur radio satellites. Modes – CW, SSB, AM, FM or any digital mode. QSOs via terrestrial repeaters will NOT be allowed. Call sign, Name, RS(T) Report, QTH and grid locator at least 6 characters and 10 preferred. There is a bonus for your first satellite or digital mode QSO. Also there is a bonus for your first RaDAR to RaDAR intercontinental QSO.

There are two contest managers:
Eddie Leighton ZS6BNE for IARU 1 see
and Marcus Kessler NX5MK for RaDAR America You will find the contest details at those links.

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 with the RaDAR Community on Google+ See

Monday, March 10, 2014

Pondering the Unknowable

There are events like Field Day and Jamboree On The Air, JOTA, that you might be willing to invest more time on an antennas and run more than QRP. I had an opportunity like that this Saturday at a local home show. In  short, I used the Icom 7100 between 20 and 40 watts and an elevated doublet using the SGC 237 Tuner. It was handy to remote the tuner and the antenna from the operating position. I was able to sustain ops at that level for about 4 hours on a 15 AH LiFePO4 battery. The battery had plenty of juice left as I only used 6 AH but the 7100 started shutting down due low voltage around 11.5 while tuning.  I looks like operating on battery for Field Day with the 7100 would be tough. Note, I did get through the entire Field Day last year with the KX3 and the same 15 AH battery.

Likewise, would I have done about as well with the Alexloop as the elevated doublet. I did operate at the home show last year. I looked back and I had about the same rate of QSOs with the KX3 and the Alexloop. So are the extra power and the more extensive antenna worth it? The answer is unknowable, but I rarely feel that I did better with the extra power and larger antennas. I think there is a level you might reach where you command the frequency with a amp and a beam. But if you are hunt and peck the rate is pretty constant.

I see operating as a continuing series of imperfect experiments. Based on these experiments I can make my choices for future operating opportunities. In fact, for the April 5th RaDAR contest I am going with Alexloop exclusively while last year I used end feds antennas and  a 31 foot poles. This will minimize setup time and will be easy to transport by foot the required one kilometer between locations.

In any case, I enjoyed operating outdoors at the Home Show and the weather was nice. The antenna setup was fun. The bleachers helped get the 44 foot doublet about 45 feet high at the peak. The doublet was made from 300 ohm feedline and split for 22 feet on each side. The SGC 237 at the bottom of 31 foot Jackite pole. Then 70 feet of RG8X to Icom 7100. The doublet tuned fine 30 meters and up but would not tune 40 meters. 6 AH was used over four hours for 16 QSOs using between 20 and 40 watts. The rig started shutting down on transmit at key down to tune volts about 11.5. Battery had lots of life left with voltage at 13 volts on receive. So I switched to KX3.

20 QSOs:
30m CW 1,
20m CW 3,
17m CW 1 SSB 3,
15m CW 6 SSB 1,
12m CW 1 SSB 1,
10m CW 1 SSB 2.

DX Canada, Netherlands, Hungary, Puerto Rico 2. 
States MO 2, NJ 2, MA, MN, MI 2, TX 2, ID, NY, VA and KS.

Oh yes I had a relay QSO with Marcus NX5MK via KD2AJT Louise. His Alpha Loop was doing well to NY.

44 foot doublet

SGC 237 Tuner

Icom 7100

Last year's setup for Home Show