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nRF51822 QFAC with Johanson 2450BM14E0003 balun and IFA

I'm having really terrible RF performance with a PCB I've designed using a nRF51822 QFAC, Johanson 2450BM14E0003 balun, and a PCB IFA (from TI DN0007: www.ti.com/.../swru120b.pdf). I can only get about 20cm range max before I loose the connection, which seems crazy low for even a pretty mis-matched antenna.

As far as I can tell, I've matched the reference design quite closely, so I'm not sure why I'm seeing such poor performance - though I'm certainly not experienced in this area either. Unfortunately I don't have any test equipment available that is capable of showing me what's going on here.

Reading other threads here on designs that use baluns, and I get the impression that I should be seeing "good enough" performance like this as I'm using the recommended balun for the device, though if I wanted to properly tune the antenna to my PCB's layout I'd have to add a shunt capacitor between the balun and antenna to ground, and tune the antenna's length (but no test equipment...).

Am I completely off track here? What are the simplest steps I can take to reach a few metres range at a minimum? I don't need great performance at this stage, just something that's usable for prototype work. Of course, perfect performance would be a nice to have. ;)

schematic

PCB

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