Davids article which I have converted to PDF and made available from this page is what I based my orginal Portable "builders Line dipole" on. The last page of the article is the current bridge developed (not sure certainly provided) by Murray Greenman ZL1BPU for light weight QRP to QRPP operations. The article in an earlier draft was published in the NZART BreakIn however the bridge never made copy.
Intriguingly I have been able to use somewhat this on 2 metres and indicatively on 70cm, however it's a dummy load on 6m.
In recent review of artcles on theparrallel LC tuner for the End Feed Half Wave aerials I have seen reference to similar circuits for SWR indication. It is of note this circuit from this page does not measure SWR, it indicates the current balance. The more you move from resonance the higher the imbalance. Read Murray's work and see what I mean for your self.
73 Trevor
