2M J-Pole Antenna Give-away - Update

The winner of the drawing for the 2M J-Pole from Hamuniverse.com/KB9VBR will be announced on August 29, 2001.

Previously mentioned here.

2M J-Pole Antenna Give-away

Hamuniverse.com/KB9VBR 2 Meter J-pole Giveaway - free including shipping to any US licensed ham. Details are here. You have to send an e-mail to enter and the drawing date has not been announced (red flag?), so you will have to check back on the website. I'll post when I see a date.



Via eHam.net

Rubberized Telescopic Antenna for Hand-Held Radios

Kinda of a neat idea... a rubberized telescopic antenna might get you the best of both worlds - performance and size. I posted about Julian's review of various 2M antennas and that got me interested in the telescoping options.

Phil, G3YPQ, posted to the UV-3R Yahoo Group about an antenna he is selling:

"Now I must declare an interest here as I supply these replacement antennas, but they are ideal for the any Handie including the UV-3R.
Its a rubberised Telescopic that extends to 1/4 wave on 2m and can be used with low SWR on 70cms either Fully down or Fully up.
On the UV-3R the LED and its surround is close to the Antenna socket so for these I shave off the rubber a little and it fits fine. It out-performs the supplied antennas without the need to change, and folds up nicely. I've been into handhelds since the crystal controlled KP202 and this things good, you can set it to exact 1/4 wave on marine band by telescoping the top section down."

He is selling them on ebay for about $28 including shipping.

Here are his notes for the video:

"Replacement for supplied rubber-duck aerials. This has advantages of being able to 'tune' as 1/4 wave as well as to easily clip on an extension for lower frequency reception"

Shootout in the Lake District

How's that for a sensational headline? Second runner-up, was "size matters."

The story in question is actually about a comparison of various antennas for the 2 meter band. The author lives in Cumbria, the Lake District in the UK. (My in-laws lived there and I managed to visit once. It is a very beautiful place.)

What I found most interesting is how poorly some of the antennas performed. You never want an "upgrade" that moves you in the wrong direction. G4ILO says the telescoping antennas are inexpensive. Sounds like they'd be worth having around for a doubling of effective power and their convenient form factor. It is amazing how the last three antennas can really make a huge difference in your performance. Hams always talk about investing in antennas over everything else and this really drives that lesson home.

Here is a summary... measurements are relative to the stock antenna and I've done some rounding.

- 2in. 144MHz stubby ................................................................. -5dB
- A-137 dual band stubby ............................................................ -5dB
- 2m Stubby Duck from Smiley Antenna ................................... -2dB
- 6in. 2m helical antenna (from a TH-205E HT) ......................... -1dB
- Nagoya NA-701 dual band BNC antenna ................................... +0dB
- 8in. 2m helical antenna ............................................................ +0dB
- Standard Yaesu VX-8GR antenna ............................................. +0dB
- Yaesu FT-817ND standard antenna ........................................ +1dB
- A quarter wave telescopic BNC whip (19in) .............................. +3dB
- Nagoya NA-767 (38in) ............................................................ +9dB
- Sharman RH-770 dual band antenna (Diamond RH-770 clone) ..... +10dB
- 45.5inch Black Whip (5/8 wave single band) .............................. +11dB

New Ham Radio Setup - A Short Checklist

After we got the ICOM IC-7000 connected and powered up, my father-in-law/elmer suggested a few best practices.

1. Turn the transmit power down. This is good for a few reasons. If you don't have a good match to the antenna you might burn out your finals. When you are doing basic testing, you don't need to push max power into a dummy load.

2. Set the microphone gain. It is always a good idea to make sure you aren't too hot into the mic. The other hams will let you know if you "need to back off the mic." The IC-7000 has an ALC (Automatic Level Control) to smooth out the peaks. (We actually transmitted into the dummy load to adjust the settings - see #3).

3. Transmit into a dummy load. My father-in-law brought his Bird Wattmeter along with a MFJ Dummy Load and we connected it to the radio. We watched the meter and checked that the expected output matched what the meter was reading. The Bird can do forward and reflected power readings, so you could calculate SWR if you like. We got good readings during our testing - 5W out looked like 5W on the meter.

4. Check the SWR on the antenna. He also brought his MFJ-259B SWR Analyzer, so we used it to check our work on the dipoles and the ground plane install. You'll want to make sure your power is turned down, the frequency is clear, and that you are transmitting within your privileges. An ideal transmission line would have a 1:1 SWR. On the 10M and 20M, we were close to 1:1.5. The 15M wasn't as good as of a match. I need to play with the length, but I've not had time. Of course, I've not tried to do much on HF, so it hasn't mattered a whole lot.

Antenna Install Video

My father-in-law helped* me install four antennas in my attic and terminate them in a outlet box in my bonus room. I've passed both my Technician and General exams this year, but have zero practical experience, so I learned a lot. (I would draw a parallel between my General license and those guys that go to a MCSE boot camp to get certified. They spend a week to pass several exams and become what we call a "paper MCSE." They've got the creditials, but no experience. That's me when it comes to ham radio.)

We were lucky that the back side of the wall in the bonus room was unfinished. It made it easy to mount the box and run the cables into the attic. It was interesting to me that my father-in-law didn't use a lot of fancy, single-purpose tools. He scored the drywall with an exacto knife and did all his cable striping with his pocket knife.

He had made the 2M quarter wave ground plane antenna some time ago. He brought the PFC pipe and just trimmed it to fit. He also made the termination fixture from aluminium angle he had in his workshop.

He had some insulators laying around that he gave me for the HF antennas. He pulled the wire from his collection of random bits he has acquired over the years. We went to the ARRL Handbook (1999 Edition) and got the formula to calculate the lengths for the dipoles on the three bands. It was simple math (468 divided by the frequency to get the length of the antenna), but it was neat to do the calculation along with the hands-on work.



I really made out like a bandit since he provided everything... wire, connectors, outlet box, outlet cover, coax, insulators, solder, etc. He even loaned me his wattmeter and SWR meter. (More on those later.)

* Helped = means he did most of the work and had all of the know-how.