Satellite QSO — L-Band AO-92

Finally managed to work an L-band AO-92 QSO today. Thank you AA5PK and WD9EWK for coming back to me.

Nearby you can see my poolside deck set up. With my push up mast on the ground and in the trash, every time I want to work satellites I lug the rig out to the deck or I go on a rover expedition. That, of course, is how lots of people work satellites.

For L-band I need to lug the IC-9100 rather than the far lighter IC-910H. Last Sunday I gave it a go and got nothing. This Sunday, I tried adjusting the uplink frequency but still nothing.

After ruling out the cable to the Wimo Helix, I decided to look more closely at the antenna. Bingo! I discovered a short right at the feedpoint.

Perhaps it was working when the antenna first arrived, because I could hear a couple of stations during a VHF contest but couldn’t work them. This morning I discovered that the point where the helix is bolted to the center conductor of the N-connector was a dead short to the reflector. I found a couple of tiny washers to provide sufficient offset to prevent a short and it worked.

One underlying issue, that I need to correct if I want to do more work on this band, is that I don’t have a way to measure SWR or resonance with an antenna analyser.

I found that the IC-9100 will show full power whether the antenna is connected or not. I can understand why Icom doesn’t have the same SWR measures as they do for all the other bands on the rig, including 2 m and 70 cm. I’m sure it would be both challenging and costly to add it for 1296 MHz.

One other challenge this morning was that by the time I got things working, I was on a western pass of AO-92. For those passes I have a house and lots of trees in the way. I was able to make my contacts through a slight window between the house and trees. The eastern pass is much better. Will give that a go next Sunday.

Good luck in your efforts to work L-band on AO-92. It’s nice to work on one more technical challenge and actually get it to work.