M802 SSB transmission problems

[alctel]

Also - the studs on the AT140 you connect the attenna and radio to rotate freely when I try to tighten nuts with the connections onto - is this usual? Otherwise I'll have to take the cover off and look inside

[Auspicious]

Originally Posted by alctel

The tuner displays tune, so I'm sure it's tuning correctly.

Weeeeelll - the tuner can match impedances. That doesn't mean your antenna is radiating effectively. Different things.

Originally Posted by alctel

I redid the antenna connection with gto15 that I had and resealed it up. I also reattached the KISS as well as the cable to the thruhull so I have two grounds, but thinking this may be a mistake.

Not a mistake at all. The KISS is a counterpoise. The connection to the thruhull is a ground. Both is best practice. We can draw direct comparisions to commercial and military installations are beyond measure. There are better counterpoises than the KISS but they don't last as long - the mechanical construction of the KISS makes it just as good in five or ten years as the day you installed given trivial maintenance.

Originally Posted by alctel

While doing that I noticed that the green earth wire that comes off the tuner control wire was connected at both the tuner and radio sides - apparently that's not a good thing?

The tuner and the radio are going to have a ground connection: the coax shield and the DC connection. The ground for the control wire is trivial. Of greater importance is NOT grounding the stud on the back of the 802 radio (the black box).

Originally Posted by alctel

I've already given the values I got with my clamp on ammeter, the one from the shunt shows 3 standby, 7 fsk/whistle and 5 talk (amp draw)

I remembered higher numbers. Those are low. Should be about 2A on standby/receive, 20-25A FSK/whistle and around 12-15 talk. Are you sure you are on high power? If not there is likely a foldback issue.

Originally Posted by alctel

Also - the studs on the AT140 you connect the attenna and radio to rotate freely when I try to tighten nuts with the connections onto - is this usual? Otherwise I'll have to take the cover off and look inside

Nope. Not okay. There are a slew of screws that hold the tuner cover on. You'll want an electric screwdriver. Or a teenager. One who follows directions. Open up the tuner. The nuts that are to hold the studs securely are immediately apparent. Threadlocker of some kind and/or a lock washer is recommended.

We can schedule a call on your next visit to the boat. No charge. We can jump you way ahead if I can talk to you and see. Do you have Facetime, Skype, Whatsapp, Messenger? Video calls are great for remote help. Write me dave@auspiciousworks.com . Cruisers helping cruisers.

[Brian.D]

Originally Posted by alctel

Also - the studs on the AT140 you connect the attenna and radio to rotate freely when I try to tighten nuts with the connections onto - is this usual? Otherwise I'll have to take the cover off and look inside

No rotation. Must have solid connection. Remove the cover and tighten all your internal connectors. I would also recommend tightening any screws you see. These usually are associated with the ground plane of the PCB. Make everything tight, but don't over tighten you might break something.

[alctel]

Thanks Dave - will send you an email when I'm in an area with more coverage (currently I have to hike to the top of a hill a kilometer away from my anchorage.

I will remove the 'green' wire from the stud at the back of the radio.

It seems removing and opening up the tuner is next on my list! Thanks again all.

[Auspicious]

Originally Posted by alctel

Thanks Dave - will send you an email when I'm in an area with more coverage (currently I have to hike to the top of a hill a kilometer away from my anchorage.

I will remove the 'green' wire from the stud at the back of the radio.

It seems removing and opening up the tuner is next on my list! Thanks again all.

Hi Matt,

I feel your pain with connectivity. Stories to tell. *grin*

I spent just a couple of minutes on your website so I have some context. I'm sure you've dropped your share of stuff in the bilge. I prefer soup bowls or low profile plastic storage containers over coffee cups for all the little screws that hold the AT-140 cover on. That reduces the amount of digging to recover the screws one at a time as you put things back together.

Be careful of the wires inside the tuner that go to the studs. You don't want them wrapped around the inside of the stud. There should be a little slack. I would back everything off a bit for access and put a drop of threadlocker on the stud bolt before tightening the nuts.

This is fussy. In the spirit of constructive laziness I would generally dismount the tuner entirely and take it inside the boat to open up and tighten the studs. Then put it back. You know how hard that is so will have to make your own judgment. Be careful with the control cable Molex connector. The connection is not very robust.

While you're in there look over the entire board for anything that looks scorched or melted. Use a magnifying glass if you have one. If you do this in less than about ten minutes you aren't looking carefully enough. Take pictures. They're free.

I'll watch for your email. I'm an early riser US ET so think in terms of your morning and my midday/afternoon for a phone call when you can get a signal on your boat. If I take a nap I can stay up late if that helps. My wife is used to weird hours on my part. *grin*

[Bycrick]

If you get to the point of examining the PC board for burned or damaged spots, don’t forget to open (if possible) any of the metal shielding enclosures. A few years back, a boat had a problem with the tuner clicking but not actually tuning properly. Everything looked good until we opened up the metal enclosure around the SWR-measuring components. All we found was black dust and sand particles. Apparently from a close lightning strike the previous year.

[Auspicious]

Originally Posted by Bycrick

If you get to the point of examining the PC board for burned or damaged spots, don’t forget to open (if possible) any of the metal shielding enclosures. A few years back, a boat had a problem with the tuner clicking but not actually tuning properly. Everything looked good until we opened up the metal enclosure around the SWR-measuring components. All we found was black dust and sand particles. Apparently from a close lightning strike the previous year.

Agreed on being thorough. This is why it takes ten(ish) minutes to do.

I feel obliged to say that Icom products are really robust. Most of my exposure is to units that have problems - that's what I get paid for (amongst other sins). I almost always find a problem with installation or operation. I've seen one bad AT-140 and two bad 802s. That's it. My upstream contact with Icom (to whom I still owe a forensic analysis for that latest effort) has told me that the failures I have found outnumber all others they see combined. I guess that makes me the last resort. *grin* I know you'll hear similar conclusions of robustness from friends Gary Jensen and Gordon Wood.

It's certainly feasible that the matching circuit in the tuner (it isn't really SWR) and the SWR measurement in the radio (which drives the foldback circuit) are most fragile (least robust? most exposed?) are of concern. Occam's razor however applies. Remote diagnosis is always a challenge. Video calling helps a LOT. When I can get my hands on something I can generally get it resolved in a week including parts and shipping. Most of the time it's an hour of training or improving an installation. Remote can take longer when test equipment is limited.

Regardless, I'm happy to help Matt. I know Icom doesn't want unhappy customers. They've jumped through hoops for some of my customers to provide satisfaction. In my experience they are devoted to customer service.

[Cpt Pat]

Originally Posted by Auspicious

Nope. Not okay. There are a slew of screws that hold the tuner cover on. You'll want an electric screwdriver. Or a teenager. One who follows directions. Open up the tuner. The nuts that are to hold the studs securely are immediately apparent. Threadlocker of some kind and/or a lock washer is recommended.

WARNING! Loctite is an excellent electrical insulator! Don't ever use it on any fastener that's expected to make an electrical connection! Once you put it on, you will have a very difficult - if not impossible - task of getting it off. Methylene chloride and acetone are solvents, but those chemicals may ruin any plastics they touch. Never use any thread locker on electrical fasteners. Use lock washers.

This is number one on my Top-10 list of my own stupid mistakes of the past. (Soldering a 48 conductor connector, while leaving off the fastening barrel, is number two.)

[Auspicious]

Originally Posted by Cpt Pat

WARNING! Loctite is an excellent electrical insulator! Don't ever use it on any fastener that's expected to make an electrical connection! Once you put it on, you will have a very difficult - if not impossible - task of getting it off. Methylene chloride and acetone are solvents, but those chemicals may ruin any plastics they touch. Never use any thread locker on electrical fasteners. Use lock washers.

Too much Loctite and misplaced the separate nuts for the electrical connection. The mechanical connection is close to the case and followed, separately by the nuts for the electrical.

[Brian.D]

Don't do anything that you do not feel comfortable doing. Removing the cover and tightening the thru bolts is needed. Pulling the RF Shielding cover off and looking for burnt components is not, unless when you take the cover off and you smell burnt odor.

Keep it simple for now. Fix the loose connectors and clean/replace the antenna feed point. Then test.

[alctel]

I disassembled the tuner and tightened up the screw that holds the stud the antenna connects to. It was very loose, and the internal ring connector on it was blackened, perhaps from a the poor connection? I cleaned it up and reattached, tightening everything and that seems to have done it - I can connect with remote stations and they can hear me fine.

Thanks again to everyone for all the help!

[Auspicious]

Originally Posted by alctel

I disassembled the tuner and tightened up the screw that holds the stud the antenna connects to. It was very loose, and the internal ring connector on it was blackened, perhaps from a the poor connection? I cleaned it up and reattached, tightening everything and that seems to have done it - I can connect with remote stations and they can hear me fine.

I'm glad it's working. I expect that the tuner and connection were fine at the low power (about 10W) used for tuning but arcing occurred at full power.

[Brian.D]

Bravo-Zulu, Alctel!

[alctel]

Sorry to bump this but I'm still having problems with my autopilot when transmitting.

I've choked all the wires leading to the autopilot (there are a lot of them) and it's still happening - would it be worth putting the autopilot computer unit into a metal box and seeing if it still happens? If so, would steel be ok?

[AA3JY]

Good grounding and a proper counterpoise is important..