SSB antenna and steel boat

[btrayfors]

No need to ground the radio chassis. In fact, this often creates undesirable ground loops.

Just ground the tuner to the hull, with capacitors if you're worried about corrosion. Connection can be anywhere on the hull, including way up the topsides.

The larger deck fitting and insulation seems like a good idea. GTO-15 insulation is for 15,000 volts (that's the "15").

Bill

[tkeithlu]

OK. Further test, looking for clues someone might be able to use. I bypassed the external tuner with a SWR meter, and pressed tune on the 725 alone, in CW and then USB. At 14 MHz it was off the scale both forward and backward. At 8,6,4,and 2 MHz the radio would not transmit into the antenna. Thoughts? Thanks.

[btrayfors]

Originally Posted by tkeithlu

OK. Further test, looking for clues someone might be able to use. I bypassed the external tuner with a SWR meter, and pressed tune on the 725 alone, in CW and then USB. At 14 MHz it was off the scale both forward and backward. At 8,6,4,and 2 MHz the radio would not transmit into the antenna. Thoughts? Thanks.

I wouldn't have expected anything else. If I understand correctly, you're trying to feed the transceiver output directly to the whip antenna, without any sort of tuner. Of course you're going to get high SWR at most any frequency.

You need some sort of tuner in line to tune that vertical.

What type of tuner do you now have?

In testing SSB setups, two devices are critically important to have. You already have one...the SWR meter. The second is a 50-ohm dummy load. You could, e.g., then run the output of the transmitter to the SWR meter and connect a dummy load to the meter. That would tell you immediately whether:

(1) the transceiver is putting out any power, and how much; and
(2) whether or not the coax and connectors involved are good.

A VOM can also tell you about shorts or opens in the coax line.

If everything checks out up to the tuner, and the tuner connection to antenna (GTO-15) is OK and the tuner is hooked up to some sort of RF ground, then the only possibilities left are:

(1) the tuner is defective; and/or
(2) the tuner control circuit is defective.

Bill

[El Pinguino]

I wonder if the mods could merge these two threads?
http://www.cruisersforum.com/forums/...at-156812.html

[tkeithlu]

Thank you, Bill. I will do exactly that test sequence, and will also borrow a manual tuner to temporarily replace the IT-100 automatic tuner. I have checked every cable and connection I can for continuity and resistance to ground, and found no problem, darn it.
--Tim.