Driven By Curiosity

I almost thought I had something working yesterday. I haven’t worked out the issue yet, but I’m seeing signs of life. I got and installed the baluns and chip antennas… My 802.11 access point died and confirmed that it was polluting my receiver, as I get CCA=1 now. I figure that for test purposes, I should run the CC2500 as close to 2.45GHz as possible, as that’s the center frequency for the balun/antenna. That way whatever rotten impedance matching my rework causes should be partially compensated by maximum performance of the components.
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I was a little hasty in my board design. I did NOT do sufficient design of the RF section on my boards. What I find really funny now is that it’s much more obvious to me than it was previously. In lieu of a design, I copied the matching network from the CC2500 datasheet then copied some F-antenna from somewhere else. Not smart.

Looking at it now, the matching network is a 200 ohm to 50 ohm balun, the antenna is something else, although I really don’t know what. And the other prototype boards I’ve seen with a similar antenna have very different matching networks. Hmm… Oh well. It probably would have been clever to look around more and figure out how to do a 200 ohm folded dipole as suggested on the CC2500 datasheet.
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