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Old 09-03-2008, 18:23   #46
S/V Illusion
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the noise is actually the servo motors and is normal.

If you do get an SWR meter, they are typically desgined to be connected between the antenna and tuner with coax cable connectors, specifically PL259s. As you probably don't/won't have coax feedline on the boat, a good connection becomes slightly more problematic. If you want to get an actual reflected power measurement using coax, it should ideally be done at the antenna connection, not the tuner output. This becomes kess important when you install the rig aboard using a wire feedline as the entire feedline is part of the antenna.
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Old 09-03-2008, 18:24   #47
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I may have to wait until next weekend. A lot of the nets occur while I'm at work.
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Old 09-03-2008, 20:40   #48
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Sorry to say it, but s/v Illusion must be having a bad day...or a bad dream :-)

First point. Most modern marine antenna tuners for the consumer market use latching relays to switch in capacitance and inductance, not "servo motors". It's possible that the AT-140 is an exception, but I don't think so (the AT-140 manual is particularly "thin"). It's predecessor tuners all used latching relays, as do the LDG tuners, the SGC tuners, the Kenwood tuners, etc.

Older military and commercial tuners sometimes used servo motors to adjust, e.g., a roller inductor.

Next point. The Power/SWR meter belongs in the coax between the radio and the tuner, not after the tuner. Install it close to the radio. What you want to know is how well the tuner/coupler has tuned the antenna system -- antenna and RF ground -- to the 50-ohms impedence your transceiver is looking for. So you want the meter to "see" what the radio is "seeing", which is why you install it close to the radio.

And a final point. While the family of Icom tuners will "memorize" tuning positions for favored frequencies, this feature as implemented by Icom is not very impressive compared to other tuners. For example, the AT-140 can memorize settings for up to 45 frequencies, but will only retain them for about a week if the radio isn't used. By contrast, the SG-230 tuner has 500 non-volatile memories.

What this means in the real world is that unless you use the radio frequently you'll have to put up with the whirring and clacking of the AT-140 :-)

Bill

Last edited by btrayfors; 09-03-2008 at 20:48.
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Old 12-03-2008, 11:46   #49
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Success

Today I successfully managed to send an email to myself over short wave. It's kind of a milestone and I'm hugely pleased.

I just want to express my thanks to those of you who have offered advice - particularly Bill. Cheers.
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Old 12-03-2008, 11:54   #50
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Congratulations!

Exciting stuff, this Pactor!

Take care,

Bill
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Old 18-03-2008, 16:44   #51
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I now have a need to keep things really tidy. The long counterpoise is now a problem. Question. How tight can I wrap this up and stay effective? Can I coil it up several times into a small but fat loop?
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Old 11-08-2008, 15:22   #52
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ICOM 802 - Ham frequencies ?

Hey, I'm considering getting an ICOM 802. I was excited to find this thread, and see answers here to many of my questions. GREAT !

One lingering concern: Some ICOM advertisements imply the 802 can send and recieve on ham frequencies. But, the official specifications sheet only lists the marine SSB frequencies. ( ??? )

I have a ham license, and I'd really, really like to have a radio that operate on both the marine SSB bands and the ham bands. Can the 802 do this? Does it require clipping a diode, or something?

...Rapid Roy KJ4FTG
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Old 11-08-2008, 15:36   #53
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There's a "secret" code to unlock the M802 so that you can use the Ham frequencies. You don't have to take it to a dealer or do any hardware mods.
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Old 11-08-2008, 17:49   #54
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Icom America - Knowledge Base Article 57DG1541A3
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Old 12-08-2008, 05:36   #55
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Ah ha! Found it.

Icom America - Knowledge Base Article 57DG1541A3

....Rapid Roy KJ4FTG
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