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				 Icom 802 troubleshooting 
 
			
			In article ,"Keith"  wrote:
 
 Well, I had a tech come out and check out my system. M-802 with the
 automatic antenna tuner. He said that the radio is only putting out about 50
 watts, and should be putting out 100-150 watts, so he thinks something is
 wrong with the radio (new, right outta the box...)
 
 He also mentioned that the automatic antenna tuner should be closer to the
 ground plate. In the Icom manuals, they said to mount it as close to the
 antenna as possible, so it's on the flying bridge, and the conductor from
 the tuner to the antenna is about 3'. I can move it about halfway between
 the antenna and the ground plate in the engine room. Who's right?
 
 The final thing is that I ran a 2" ground foil strip from the radio to the
 ground plate as well, as required by the ICOM manual... he said this isn't
 necessary and should be disconnected. I'm really confused now.
 
 Help!
 
 At this point, I'm going to take the radio in to the dealer and have it
 checked out and anything corrected as needed, then see how things work
 before I start moving the tuner around.
 
 
 
 Hello Keith,
 
 
 I don't know the guy you hired to do your HF Radio work, but from the
 sounds of things, he isn't one of the greatest Tech's to walk down the
 dock.  First thing, is to transmit into a Dummy Load, and see if the
 radio is capable of putting out it's rated power, into a perfect antenna.
 If yes, the problem isn't in the radio.  If no, then the radio needs to
 be realigned. (tuned)  Second, understand that any SSB Radio maybe
 transmitting rated power, and it doesn't nessesarily show up on a
 non-peak reading Wattmeter.  There are many reasons to have the
 autotuner mounted at this polace or that place.  Most are related to
 what type of RF Ground System your vessel has.  From a strictly RF
 standopoint, closer to the Ground Plate is better, and 2" copper foil
 is minimal for any connection to a RF Ground System.  what is the length
 of the copper foil in feet?  The longer the foil, the worse the ground
 impedance will be, and the harder the tuner will have to work to tune
 the antenna.  You don't tell us anything about the vessel construction,
 RF Ground System, or antenna system.  Knoing these would be critical
 in advising you on your installation.
 Points of interest.
 1. If your foil is longer than 3 or 4 Feet, then what you are asking
 that autotuner to do the almost impossible.  Think it as if the tuner
 wan't sitting at ground but at some point above ground and that point is
 the length of the copper foil.  Lets say 15 Ft, as you say it is on the
 Flying Bridge, and that is say 15 Ft above Waterline.  Now you
 effectivly have the tuner in the middle of a diopole antenna and trying
 to reconcile impedances on both antenna and ground at the same time.
 BAD IDEA.  The firmware in the tuner only looks at the antenna
 impedance, with refernce to the Ground lug on the tuner.  If the ground
 lug isn't at RF Ground, then the tuner firmware gets REALLY FUNNY DATA
 from it's internal sensers and it doesn't deal with funny data well.
 2.  If the tuner is moved to a place, say 3 ft from the RF Ground, then
 you must add wire to the antenna, and that wire becomes part of the
 antenna, and therefore gets tuned by the tuner.  This is a GOOD THING,
 if people, or Ground don't come to close to it while you are
 transmitting. By adding wire (length) to the antenna you are effectivly
 lowering the frequency that the tuner will tune.  This again is a GOOD
 THING, on a plastic or wood vessel.
 3. As Larry and Jim have stated, check and BE SURE, that the radio is
 in TUNER MODE, and not THRU MODE.  If your in THRU MODE, the tuner isn't
 even going look at your antenna, let alone try and tune it.
 
 
 More information!
 
 
 Bruce in alaska
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 add a 2 before @
 
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