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Hi Peer,

As I see it you have two different issues.

1) Disagreement between two different measuring devices

2) Some operational/calibration issues with the VA5.

Issue 1.? I assume that you are not taking your ICOM into the field so you are measuring at the input to the feeder.? If you are measuring at the same point with the VA5 then the difference is most likely the inaccuracy of the ICOM measurement.? Although I'm not familiar with the circuitry in the ICOM, it is most likely using some kind of directional coupler/bridge.? These have multiple sources of error, including source match and coupler directivity.? OSL calibration determines these errors and removes them using calculation.? This is not an option with our transceivers so we are the mercy of the basic design.

With a calibrated VA5 these errors are removed.? Now if you are actually measuring at the antenna (preferred), then you have removed the effects of the feeder.? This alone will give different results even with the same instrument.

Issue 2.? I'm not sure I understand what is happening and quite frankly I use the VA5 so infrequently it is a relearning exercise when ever I do.? I'm blessed (or perhaps plagued) with too many analyzers; an N2PK, DG8SAQ VNWA, Rig Expert AA-55 Zoom, Elekitsorparts FAA-450, and the FA-VA5.? All of the others are generally friendlier to use, but the VA5 is very accurate, portable and usable outdoors in sunlight.

Perhaps someone more familiar with it can help you out.? It is an excellent device and I wouldn't give up.

Wes? N7WS