Sunday, June 30, 2013

New Cover and Sideplates for the KX3

Here are the new side plates and cover. I used it in Rose's case and fits perfectly. My FD partner used a Pico paddle attached to the KX3. I used my favorite N3ZN single lever.

Saturday, June 29, 2013

A Very Nice Field Day Video - from WQ4RP in Raleigh NC

I wish I had a video like this - maybe for 2014.  Very nice operation and lots of camaraderie.  Way to go guys.

Wednesday, June 26, 2013

Field Day 2013

Field Day 2013 is now history.  We did something new this year in that we (WM4AA and NY4G) set-up the Class 2B station at a campground at the base of Mt Pisgah in North carolina along the Blue Ridge Parkway at 5000 feet of elevation.  It was a great campground - clean, bathroom / shower facilities, a nearby general store and trees tall enough to hang wire antennas from.  Plan A had been to use the Hexbeam along with wire antennas.  Unfortunately, the mast on the antenna did not end up in the checklist.  It never got loaded.  We had to resort to plan B.  I had made up a G0GSF (aka ZS6BKW) dipole a while back as a back up antenna.  It used 16 gauge THHN as radiators with a twin lead as a radiator/feedline.  We still had to terminate the balanced feedline from the twin lead to an unbalanced coaxial feedline - and ahad to improvise that by borrowing the termination from the hexbeam.  The pneumatic launcher worked like a charm as it launched a tennis ball clear over a 70 foot tree with plenty of height to spare.  We hung the Par end Fed Z from Matt's site along with an end fed half wave monopole.  We hung the G0GSF from the back of my site.  Here is Matt's set-up for night time ops:

Here is the setup at my camp site.  Our solar panel
Both our rigs are KX3s.  Mine is running NaP3 as a panadapter.

Here is a photo of what night time operation is like:
The views were spectacular:
All in all - 282 contacts (280 were CW) at 5 watts output.

The launcher to put up those pesky antennas

Thursday, June 20, 2013

My Version of a Pneumatic Launcher - QE21

My antenna launcher is based on the QE19 design in  The author limited his barrel length to what will fit into a Rubbermaid tote which is 19 inches in overall length.  I found a tote at Lowes which allowed a 21 inch overall length which improves performance a little bit.

The nomenclature stands for Quick Exhaust valve launcher 21 inches in overall length.

Here is the QE21 made from a 3/4" Quick Exhaust Valve and a few parts making a quick, effective and easy to build a launcher for heights up to about 150 feet.

The chamber volume for the pressurized air reservoir in the QE21 is about 75 cubic inches. It could be up to about 24" long. Longer than that doesn't buy much, and performance may suffer from friction and inadequate airflow for the barrel volume in the longer barrel. Optimal performance is expected to be near 24 inches in overall length based on the studies made by the author at . The 3/4" valve just is not big enough for high > 150 ft performance with Tennis Balls. Shorter than 18-19" the performance will also begin to drop off. Consider your transport and storage plans and size accordingly.

QE21 Performance

The performance of a QE21 should just be slightly better than the QE19 in  
With a 4 ounce tennis ball (a standard 2 ounce ball with about 22 pennies added to the interior), and towing a 30 pound kite line, this launcher has approximately the following performance:
QE19 Performance

QE21 Description

Starting at the top left is the barrel. 2.5 inch diameter schedule 40 is a tight fit for tennis balls, but does the job well.

A note here about the barrel. Schedule 40 PVC is fairly available, and Tennis balls fit quite tightly into schedule 40 barrels. It turns out that there is another PVC pipe material with a slightly thinner wall that fits Tennis balls almost perfectly. It is much easier to push the Tennis balls into SDR21 and the performance of the launcher is improved especially at low pressures. It is called SDR21 PVC and the outside diameter is the same, so it fits the PVC fittings. SDR21 is hard to find in 2.5" size, but I have also located a source at /div>

At the right end of the barrel is a 2.5" coupler, 2.5 to 2" bushing, 2" to 3/4 inch bushing, a short length of 3/4 nipple pipe and a cast elbow, a short 3/4" threaded pipe nipple, and the big aluminum object is the Deltrol 3/4" quick exhaust valve from McMaster-Carr.

Starting at the valve going left is a short threaded pipe 3/4", a bushing 3/4" threaded to 2", a 2" tee, 2" schedule 40 pipe, and on the left is a slightly special assembly. This is the end of the pressure chamber and there are two choices to go there. The easiest is a regular 2" cap.

My version in the photo uses a 2" cap. Then this assembly is glued together simply with PVC cement.

For detailed instructions please

Friday, June 14, 2013

Slow Motion Video of Pneumatic Antenna Launcher

I have made one of these launchers.  Here is a video I found on YouTue that demonstrates the action in slow motion: