1. Bill is right - by any means check via an swr-power meter... even with bad VSWR you will at least see if any power goes out - I would try on LOW power
setting first! (hoping that on this Icom
802 low power
will trigger the tuner?
2. 12.4m or about 40 ft of total antenna wire until the automatic tuner is indeed about 1/4 wavelength on 6Mhz but:
- I have experienced problems to tune 40m band (7 Mhz) on a 9.6m vertical with radials (home QTH) using a CG3000 atu....and other users of the CG3000 have mentioned the same issue when tuning a 1/4 wave wire....which sounds very odd since a 1/4 wave vertical should be about the easiest to tune
- you report about 5m/16 ft of GTO15 from the lower backstay isolator until the ATU - is that spaced well away with standoffs from the remainder of the backstay and from other (grounded) metal hardware
like pulpit..? I have seen too many boats with the GTO15 or even coax just taped/strapped around the remainder of the backstay
- how much of that 16ft is underdecks? => preferably the atu is located just below the through-deck gland and close to the backstay as mentioned before
3. If there are no issues with the Icom
802 cuttting back power (known issues) and all tuner, coax and antenna connections are OK, then a 12.5m radial (wire) along the deck
and connected to the atu ground lug, in a temparary setup, will help tuning (even if Mr. ka4wja doesn't think so) if there is a real tuning issue due to ground issues and/or problematic antenna wire length.
BTW as a temporary easy solution you might make an inverted-V wire dipole that you hoist into the mast
with a spare halyard
tying of both ends stern and aft (simple isolators even nylon rope
would do)(but fix it a far away from backstay and forestay as possible - I guess on your 11m long boat your mast
will be at least 13m high).
Of course you would need a coax feed length = mast height + length needed to get to your SSB
, connect it durectly to the antenna out without the atu. Starting length: 300/frequency in Mhz/2 x 0.96 gives about 11.07 metres per dipole leg. Hoist it when on a stable sailing tack or at anchor
, take it away when done- it should take you only 5 minutes to set it up. Do check swr when making it (60 min. max).
This should give you a good alround antenna albeit monoband but not really suited for real long range communication given its rather high takeoff angle.