Category: Antennas

The antennas that I’ve built and my impressions of them.

Testing the Pixie II

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It’s Alive!

Chinese Pixie II
My new Chinese Pixie II fully assembled and nestled in it’s Altoids tin enclosure.

Okay! I just got to test the receive part of the Pixie II… and it worked!! This is the first fixed frequency radio I’ve ever built or even heard, so I have no basis for comparison, but I can tell you that it worked and that is very exciting for me. I thought it was cool when I built a little ground plane antenna for 2m and then a 5/8 wave whip for my 2m radio, but this is really something. I know I didn’t design the radio, but just the idea that I built it from a bag of parts, put it in an Altoids tin, hooked it up to a dipole antenna that I made from some speaker wire, and heard real, live CW is amazing! To me, this is what ham radio is about. And I can’t wait to finish my next radio project of redesigning and building a variation of the qrpme.com’s Sea Sprite (which is just an improvement on the Pixie II).

Testing Different Frequencies

I went through the crystals from the 8-pack (plus the one that came with the Pixie II) and picked up transmissions on 7.030, 7.040, 7.050, 7.070 and 7.110. The first 2 probably came through the clearest, but 7.110 came through well enough for me to catch some if it. And that’s important since it’s the novice frequency and will probably be the frequency I call on first. There’s a good reference for QRP at QRP Portal. Here’s the calling frequencies chart from their site:

40m
7.003
CW
 (Japan, daytime only!) –
7.028
CW
 VK VK3YE
7.030
CW
 (Europe) AC6V, ARRL, GQRP, K3WWP, NJQRP, RU-QRP, VK3YE
7.035
CW
 (QRP-L) AC6V
7.040
CW
 (US) AC6V, ARRL, K3WWP, NJQRP, VK3YE — now moving to 7.030
7.060
CW
 (Europe) AC6V, NJQRP
7.090
SSB
 (Europe) GQRP, NJQRP, RU-QRP
7.110
CW
 US Novice AC6V, ARRL, K3WWP, NJQRP
7.285
SSB
 AC6V, ARRL, NJQRP

So 3 out of 5 are primarily CW frequencies, 7.070 is PSK31 for regions 1 and 2, and I guess 7.050 is CW and digital modes. While I was able to pick up some transmissions, boy was that confusing! It’s going to really take some work to pick out a single station. They’re all stacked on top of each other! I probably heard 4 or 5 different stations on every frequency I picked up. Fortunately for me, I built a little 1/2 watt audio amplifier I built a little while back that worked great with the Pixie II. Though I was able to hear the stations with regular headphones, the amplifier really helped to pick out the individual stations.

Now I just need to find the time to finish learning CW and play with my new toy. I think a CW decoder may be in order for practice.

Back on 2m!

russell Leave a comment

I finally finished my new 2 meter 5/8 wave whip antenna, tested it and installed it on my roof. I got the design from the 1986 ARRL Handbook. It’s a very simple design, but with everything else, it took me awhile to get everything together. The original design called for a 3/4″ x 3 1/2″ acrylic cylinder, but I wound up using a short length of 1/2″ PVC (approx. 3/4″ OD) with a screw on cap. Later it occurred to me that I could have used one of those acrylic toilet plunger handles. Maybe I’ll switch to that when I install it on my truck. For now, the PVC is working just fine, and I’m sure you could use pretty much anything close to the right diameter and is non-conductive.

I had some trouble understanding how to actually connect the antenna to my radio and how to mount it. The tap on the 4th coil is soldered to the point in the SO239, while the ground at the very bottom of the coil can just be screwed down to whatever you’re using for your ground plane. After some thought, I understood that that means the antenna assembly itself doesn’t have to affix to the ground plane. Mine is zip-tied to a 2×4 that is in turn zip-tied to the vent that my feed line feeds into. I’m not sure it’s totally necessary, but I also connected the outer part of the SO239 to ground. Whether or not it’s necessary, it doesn’t seem to hurt anything.

It performed well for both RX and TX during the initial test on my balcony, and I have now tested it in it’s semi-permanent home on the roof. It works great. The roof acts as a giant ground plane just as expected. The vent that it’s attached to comes into the back closet where my little ‘shack is which is absolutely perfect! I have leftover cable from a 20’ line!

2m whip

I apologize for the one terrible picture. I don’t know what I was thinking. I’ll update the picture when I install the 11m or 10m dipole.

Next up, 11m half wave dipole for and old CB radio that was my Dad’s. If the radio works, I want to modify the radio to 10m. It should be relatively simple since it’s a PLL (Phase Locked Loop) radio.