For some reason the other day, I started thinking about slinky dipoles. I am partial to 40 meters, even though I spent most of my operating time on 15 and 20 (when 20 was working, alas).
So, I am working on building a slinky dipole. Original metal slinkys (slinkies?) are available at Wal-Mart, I paid $1.94 each for them. I picked up a 3/4-inch PVC Tee fitting and 2 half-inch plugs which are snug fit into the tee, and some 3/16-inch eye bolts at Home Depot for about $3.75. The single most expensive piece was a BNC bulkhead jack from Radio Shack for $2.99. I also bought the BNC to UHF adapter for $5.99. I splurged.
I have invested about 30 minutes total into it so far, and have drilled out all the necessary holes. Next step is soldering everything together and tuning up.
We'll see how it goes.
Went out to the car at lunch today and tuned around on 40. I decided to look around the high end of the CW band for a change, and heard Jim, WJ0C, calling CQ on 7140 KHz (plus or minus eyeball calibration). Gave him a call, and had a short QSO. He is in Waterloo, Iowa, about 720 miles from me. Copy was a little rough on his end but we had a nice exchange despite it.
I usually stay between 7030 and 7070 KHz, so this was a little different. At night, everything above 7100 is pretty well covered up by big broadcast stations, and working anyone up there is a real challenge.
The only challenge today was the mediocre band conditions on 40.
I have finished building the Slinky dipole I mentioned below. I hung it between the walls of my garage to try out, in keeping with the tradition of the Slinky being a "stealth" antenna.
A quick scan with an antenna analyzer showed it has a natural resonance around 8 MHz, when stretched out to the full width of the garage. It also has resonant points at 18, 21, and 25 MHz. I am able to get 1:1 SWR on 40 meters using the tuner, and one interesting thing is that once the tuner is set for minimum reflected power, I can tune up and down the band without retouching the tuner. This is impossible with the mobile antenna, which has to be retuned after moving only 20-30 KHz.
I haven't tried it on the air as yet, because 40 was covered up with RTTY today, undoubtedly for a contest. I will give it a shot before too long and see how well it works. It certainly sounds good on receive, so I am hopeful it will work well on transmit also.
It's been a few days so I need to catch up on things. First of all, I was looking at John Harper's web pages, where I saw mention of the QRP Fox Hunt, which is running on 80 meters every Tuesday night and on 40 meters every Thursday night (at least for a few more weeks). This sounded like something I had to try out, so at 8:00 PM last Thursday I forwent My Name is Earl and tuned up 40 instead.
This was more challenging than I had even imagined. 40 after dark is pretty much bedlam, but after about 30 minutes, I heard the hounds sending exchanges with the fox. He was working split, listening up about 1 khz. Now the RIT on the MFJ-9040 is around 800 Hz at most, but I cranked it as far down as I could and tuned up as far as I could and still hear Juan, KG4FSN, in the receiver, and sent my call, one time. I was mostly intending it as a warmup, figuring to perfect my technique later as I got the hang of things. I was totally astonished to hear my own call coming back to me from Juan, so astonished I didn't answer his first call. Surely I was hallucinating. But, no, he's sending it again. I quickly respond with a signal report, my name, state, and power, all in the wrong order, but he gets it and sends a TU back.
My 1st time in the fox hunt, sent my call one time, and got a response. That was amazing.
Today I went to 15 to listen around and heard different hams calling CQ NA for the North American QSO Party. I decided to answer a few, no intention of sending in any logs, but I was interested to see who would answer.
In fairly short order I worked six stations, in Oregon, Washington, and British Columbia. All the skip was from the northwest.
I decided to try 40, and while I was at it, to see what I could do using the Slinky Dipole that I hung in the garage. I had decided earlier that it wasn't going to be a good performer, due I think to the foil covered wall insulation around the garage. But a contest is one way to see just how well it might be working.
So in about 40 minutes of tuning around and calling only the loudest stations, I worked Texas, Tennessee, Kansas, and Wisconsin. I could tell these guys were struggling to pull me out of the mud, so I made them work for the contact.
But that's not bad considering the antenna is naturally resonant around 8 MHz and has an SWR that pegs the needle at 7, so after I fix it with the tuner it probably has so much feedline loss that my power at the antenna is maybe 1 watt.
I need to try it outside, and I need to get two more Slinkys to lengthen it for better SWR on 40.
Until next time,
73 from WA5ICA
I had to drive to Houston Monday for a meeting, and on the way down I listened to 40 meters. About an hour out of Houston I worked Jim, KC0JKD in Missouri, and then Fred, N4PHH in Florida. All this while going 70 mph on I-45 in heavy traffic, including lots of 18-wheelers. It was actually easier than I thought it would be, even considering that I had to drive one-handed while transmitting.
The only tricky part was writing down their FISTS numbers while driving.
Tonight I joined the QRP Fox Hunt for the Thursday night 40 meter hunt. I was totally skunked last week, never hearing either station or the pack calling them. But tonight I found the high fox, Dennis N4DD right away. I called him about 20 times before I hit the sweet spot where he was listening. Then I tuned for about 5 minutes until I found the low fox, Craig VE4WI, who was in such a tight spot he was listening on his own frequency for calls. I was able to get an exchange after only 5 tries.
So I got my first QRP Fox Hunt two-fer. I really enjoy the challenge of finding and contacting these guys while everyone runs 5 watts or less. My first night was a fluke, getting an answer on the 1st call, so tonight was more typical. Still, a twofer is a pretty satisfying accomplishment from where I sit.
And that is in my truck in the driveway, of course.
Til next time, best 73.