Sunday, June 12, 2016

RV05 NPOTA Activation

The Ozark National Scenic Riverway is located in south central Missouri and covers a large number of square miles. Access from St. Louis is a long drive through a lot of twisting roads. After a 3 1/2 hour drive we arrived at the Alley Mill which is located in Alley Spring MO. This trip was planned mainly using Google Earth as the rules for a scenic waterway is you must operate within 100 feet of the water. I picked the out flow of the Alley Spring before it feeds into the river because these are prime floating and partying area once the weather turns warm and I was hoping that the folks would not be on this section of water. Luckily I was correct and the location worked ok but there was a 100 foot tall rock wall about 125 feet to my east. It is hard to tell if that impacted my signal or not.

I set up in a parking spot that was 40 feet from the waters edge. Operation was from the truck as it was a 95 degree day and there was not much room to set up a table. I was able to operate for 2 hours and 14 minutes and made 134 contacts. 40 meters was my main band but I did make 20 contacts on 20 meters. I could have operated longer but I had a long drive home and this was more of a scouting mission than a long activation.

Equipment used

Power source:  truck
AH-4 tuner
32 foot fiberglass telescoping mast on trailer hitch mount
wire was spiral wound on mast
Samsung Android tablet
Hamlog app
bluetooth keyboard
Pigtail interface from Pignology
Heil BM-10 headset
Homemade PTT switch

Hard to see in the picture above but the tablet is hanging on the steering wheel. The keyboard is below it on a steering wheel tray table. IC-7100 control head is on a cupholder mount. 

PTT switch worked great. Switch is very sensitive so no finger fatigue. 

Friday, June 10, 2016

Quick and dirty PTT switch

I am planning a NPOTA activation tomorrow and I wanted another PTT switch other than the one on the headset. I picked up a couple of momentary switches and planned on using one mounted in a small box. Looking at the switch I wondered if it would fit any common PVC tubes. It does not but it does fit into a 3/4" PVC Tee. Fits in my hand pretty well. I will try it out!

I do need to find a way to provide the cable some strain relief.

Sunday, June 5, 2016

150 NPOTA contacts!!!

After a successful weekend as a chaser I was able to reach 150 confirmed park contacts! The National Parks on the Air is a great program for amateur radio. As for the NPS, I have learned so much about the park system this year and the history it represents. I love reading about the different units as I work them.

I hope to do some more activations this summer and all the way to New Years Eve!

Saturday, June 4, 2016

20 meter elevated vertical build and testing

Reason for project

Operating during a few state QSO parties and Winter Field Day showed the advantage of using a NVIS 40 meter dipole. This works great for pulling in the county multipliers or surrounding states but causes a low number of state multipliers. My thought was that I needed something on 20 meters to help grab the east and west coast states since I usually cannot put up a high dipole. 

The mast

I use a Max-Gain 32 foot push up mast with a drive on mast holder. This allows me to pull up a inverted V dipole. I have made various PVC adapters to fit the top section of this mast. 
These adapters include: Dual band 2M/70CM antenna, 2M yagi and arms to pull up dipoles.

New PVC adapter

A PVC adapter was made that allows the use of a MFJ 17 foot telescoping antenna to be top mounted on the Max-Gain mast. The adapter has a 3/8x24 threaded fitting for the antenna connection. It has a support guide about 18" above the base to provide support for the antenna and to take the wind loading off of the 3/8 x 24 mount. The 3 tuned radials hook onto to a cable tie with plastic S-clips. The radials have banana plugs that plug into the ground side of the 3/8 x 24 fitting. The PVC dog leg on the bottom is for pulling up the dipole.

Finished product

Here is a picture of it in the air with the base at about 25 feet. Height to the tip of the antenna would be around 40 feet. The 3 radials also act as guy anchors which I have at about a 45 degree angle. During the first measurement I had the antenna at 16.5 feet which should have been just right for 14.225Mhz but it measured resonant at 14.9Mhz. I lowered the mast and extended the antenna to 17 feet. This brought the resonant point to 14.110Mhz which is lower than I wanted but it turns out the VSWR is acceptable for the entire band. 1.25:1 or less for the entire band. Measurements were made with a RigExperts AA-54. I am able to save and view my VSWR graph on the PC but I cannot find a way to display it here on the blog.