After having my suspicions on a couple of recent activations I have this evening come to the conclusion that my FT817 has developed a fault. Experimentation has lead me to the realisation that power output on 2m is considerably reduced - of the order of 1 Watt on the high power settings. The rig indicates a high SWR (4 bars) and the PO display is only around 3-4 bars. On the lower power settings I see readings of around 0.5 and 0.3 Watts.
Strangely enough the problem does not seem to be present on UHF or HF though I admit I haven’t been exhaustive in my tests on these bands.
I’ve used an external SWR meter to measure the output power which while not particularly accurate has in the past demonstrated an accuracy of around 10% down to the 0.5 Watts level.
The problem manifests itself via both front and rear antenna sockets.
I’ve tried a couple of antennas both of which seem fine with other rigs.
I’ve tried running the rig off both its AC adaptor and a SLAB.
I’ve tried the various reset options detailed in the manual.
I’ve had a look inside and there do not appear to be any obvious signs of component failure.
Does anyone out there have any experience of similar problems or have any ideas for things I could try before I bite the bullet and send it off to the Yaesu for repair?