Thursday, August 11, 2005

My first Ham contact

Last night I made my first ham contact. But first, a discussion about antennas.

As I previously posted, for my first radio I picked up a Yaesu VX-5RS handy talkie ("HT"). As with most other HTs, it came with a "rubber ducky" antenna. Rubber duckies are good for compactness but not much else. They don't work well if you don't have direct line of sight to the other party to your radio conversation.

One way to improve the situation is to use a J-Pole antenna. They can be constructed cheaply from 300 Ohm twin-lead TV antenna wire. So, over the weekend I picked up a 50 foot lenght of the stuff, along with a 10 foot RG58 coaxial cable terminated with BNC connectors on both ends.

The problem I ran into when making the J-Pole was that I kept breaking one wire or another when trying to strip off a length of it. After several tries and many cusswords, I decided to look around the house and see what other kind of wire I had that I could use. Then I remembered I had a bunch of Romex 3 conductor electrical wire, as used in AC house wiring. I had a scrap piece that was about the right length. Bingo!

The Romex conductors are solid copper, rather than the stranded conductors found in twin-lead. Also, they are a much heavier gauge. After I stripped off the outer sheath, I used the two insulated wires, setting aside the uninsulated wire used for a ground. I was then easily able to strip a couple of inches off the end of each wire. I bent about a quarter inch at each end and soldered them together after placing them in a vice.

Then I cut one BNC connector off the piece of coax, stripped it so a length of the center conductor was exposed, and twisted the braided shield into a wire. The center conductor got soldered to the white piece of Romex, while I soldered the braid to the black piece.

I cut the black piece to the same length as shown in the linked diagram, you don't need the piece above the cut. The white piece was cut to 54". To keep the two wires separated, I took some wood pegs I had on hand and used them as spacers, holding them in place with electrical tape. The soldered joints were also taped.

Finally, I made a loop with a plastic cable tie and taped it to the end of the J-Pole, so the whole thing can be hung up.

I'll admit, it looks like a Bubba job, but as I found out, it works pretty darn well.

I took my new antenna and the radio into the den and looked around for something to hang it on. Nothing, so I went back into my shop and got a 4 foot plastic level, which I jammed vertically in between the cushions on my sofa, and hung the J-Pole on it using a tie wrap. Bubba indeed!

Connecting the coax to my radio in lieu of the rubber ducky, I tuned to around 145 Mhz and started scanning. I quickly came upon the Wednesday night WB3JOE MARC net on 145.130 MHz. After RTFMing, I setup the Yaesu to connect to the repeater and join the net.

It should be noted that the repeater is located in Paoli, about 15 miles away from me in Plymouth Meeting. So, it seems to me that the antenna works pretty well considering (a) the distance I am from the repeater, (b) the fact that I was inside at ground level, and (c) the low power -- 5W -- I was transmitting. It should work even better outside with the antenna elevated more.

The net had participants from as far away as Lancaster, PA and Avalon, NJ, although I'm not sure if they were connecting via linked repeaters or directly. Net control was handled by Ian, KB3JAH. Everyone was very welcoming to this newbie and I'm looking forward to future nets.

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