ICOM M 802 SSB Install: Cabling and Ferrites???

[muttskie]

Ahoy,

I am installing an ICOM M802 with the AT140 tuner.

The cabling and coax run, between the AT140 and the receiver, is right around 25 feet and there is no other option than to run the two near many other various GPS coax cables, NMNE 2000 cables, autopilot control cables, and other assorted wiring.

I have purchased a good selection of #31 clamp-on ferrite cores, but don't have a clue as to were to put them.

I also have a T4-Plus line isolator that I will install at the AT 140 coaxial ( LMR 400 ) connection.

The 12V power is clean, via dedicated AWG2, from the house bank, 420ah, ( 15 feet, one way ) to the 30A circuit breaker switch, which is located adjacent to the receiver.

The cables from the receiver to the control head, and the speaker, are about 8 feet along the same path as the antenna coax/AT140 cable.

The antenna wire from the AT140 to the backstay connection will be about 3-4 feet, using GTO 15 wire.

The boat has the built in SSB ground plane that is throughout the hull and the AT140 will connect directly to that.

Of course, I am trying to minimize electromagnetic noise as much as possible.

Any suggestions regarding the ferrite core placements? And, perhaps a dummies guide regarding ferrites, in general? Other installation comments?

This is your cue, John

Thanks,
Bill

[wrwakefield]

Hi Bill,

I'm no radio expert, but learned everything I needed to know when I installed our ICOM M802 [replacing a functioning M710] from this book:

Icom IC - M802 Made Simple for Cruisers: by T L Sparks CDR

This book also contains a useful section on how to use the DSC function for non-emergency communications [in addition to emergency coms of course...] which has been handy with some cruising buddies. I just have to refer them to the directions in this book and they can set up for DSC between our vessels. [Like you may do now with VHF DSC.]

Among many, other good US resources include:

Farallon Electronics [Who also have a good installation guide on their site.]
Dockside Radio

Regarding ferrites, usually you put them close to the power lead inputs and sometimes need to loop the twisted 12VDC leads through the core once or twice. I remember reading about other placements as part of the installation and troubleshooting section of the Sparks book linked above, but don't recall specifics.

In hopes this helps you continue your progresses finishing your project.

Cheers!

Bill

[svadagio]

When I installed my 802 and a inverter charger the people at Magnum were very helpful also. The engineer recommended a special ferrite which I bought and used. I was amazed at the difference it made. I will try to find the number and post it. It turns out the clip on and many more have a low mue(sp).
Bob

[Mycroft]

Yes, ferrites should be as close to connection as possible. Make sure you protect the positive conductor at the source (battery) with a fuse. I would recommend the MRBF type.

https://www.fisheriessupply.com/blue...se-blocks-2151

[Frankly]

When I installed my 802 I located the tuner in the laz right next to the backstay, the radio power unit in the quarter berth (opposite side) along with the Pactor modem, and control/ speaker unit at the Nav station. T4 line isolator right next to tuner and copper strap to dynaplate (now removed and replaced by centerboard hardware) from tuner to centerboard pipe. Ferrites on all lines going fwd (radio and modem) to the nav station (multiple loops where possible). Ferrites located back with the radio/ modem. Also connected the 802 power unit to the ground system.

Unit has worked for 10 years with no apparent issues other than the Danfoss refrigeration motor controller. Nothing I have tried will shut that thing up other than turning off the breaker.

Also have a good robust power feed from the main 12V distribution bus to the power unit.

[ka4wja]

Bill,
Okay, here's the short skinny!
It all looks good!
(you're following both the "Sailmail Primer" recommendations as well as those of most/all professional marine SSB installers....and you're looking good!)


Please be sure to read the "sticky" right at the top of the Marine Electronics page here....where you'll find all the references / links to just about everything "marine radio related", including the answers to these questions....(and I'll be adding more to that soon!)
http://www.cruisersforum.com/forums/...tc-133496.html




Here are a few brief specifics, in red....

Originally Posted by muttskie

I am installing an ICOM M802 with the AT140 tuner.

The cabling and coax run, between the AT140 and the receiver, is right around 25 feet and there is no other option than to run the two near many other various GPS coax cables, NMNE 2000 cables, autopilot control cables, and other assorted wiring.

I have purchased a good selection of #31 clamp-on ferrite cores, but don't have a clue as to were to put them.
In short, put them everywhere except for on the GTO-15 wire!!

In actual practice, you'll probably find the best / most effective placement to be on:
a) the tuner control wiring, both ends....but start with the tuner end first..
b) ALL the other wiring in this same area, such as your NMEA 2000, GPS, autopilot control cables, etc...place them at BOTH ends of all of these cables...
c) all the various cables going into / out-of the M-802, such as all your modem cabling, NMEA input, remote head cable, speaker wires, tuner control wires, etc....even the DC power wires (although this is probably not necessary with your power wiring, it couldn't hurt....and is what I've done)


I also have a T4-Plus line isolator that I will install at the AT 140 coaxial ( LMR 400 ) connection.
Having the T-4 isolator is great!!
(FYI, the T-4 will provide as much common-mode isolation as a dozen or more Mix #31 ferrites, so adding ferrites to the coax line is usually unnecessary....but I have some on the transmitter end of my coax...)

BUT...
But, your choice of LMR-400 is unfortunate.....this is a cable that I would never recommend for normal HF operation, let alone that in a marine environ....it has a copper-clad, solid alum center-conductor, and is very stiff/difficult to maneuver and run in tight spots....you CANNOT bend it tight, nor kink it without ruining it....the thin tinned-copper braid is easily damaged if the jacket of the cable is pierced (albeit difficult), and being laid-onto the bonded alum foil tape, makes this a corrosion problem in the making....

Also, you will need to purchase special, crimp-on connectors as well as the crimp tool / die, just to install a couple connectors....(although buying pre-made cable assemblies eliminates this issue, it adds another issue of having the big connector on a stiff cable, making even more of a pain in ass to install properly)

While LMR-400UF eliminates some of these issues, it is still a cable that requires extra care on installation, as well as the same connector issues, etc.

All in all, you'd be better off returning the LMR-400, and buying some quality (Belden, Times, Davis, Commscope) RG-213....or even some Belden RG-8x, would be better than the LMR-400....





The 12V power is clean, via dedicated AWG2, from the house bank, 420ah, ( 15 feet, one way ) to the 30A circuit breaker switch, which is located adjacent to the receiver.

The cables from the receiver to the control head, and the speaker, are about 8 feet along the same path as the antenna coax/AT140 cable.

The antenna wire from the AT140 to the backstay connection will be about 3-4 feet, using GTO 15 wire.
All this looks good....




The boat has the built in SSB ground plane that is throughout the hull and the AT140 will connect directly to that.
Take note that "anything" will work....including nothing at all....so, this will probably be okay...but...
But, having a low-impedance direct sea water connection, allowing you to use the sea water as your primary RF Ground / Antenna Ground, will be much better!!!
(any bronze thru-hulls within 8' of your AT-140?? Run a 3" wide copper strap to it, and you'll be good to go!)


Of course, I am trying to minimize electromagnetic noise as much as possible.
Watch the videos....


Any suggestions regarding the ferrite core placements?
See details above...


And, perhaps a dummies guide regarding ferrites, in general? Other installation comments?
Bill, you are not the only one asking!!!
I get plenty of e-mails and PM's asking this....and even got 2-3 today!!!
SO...

So, instead of rambling on, I will refer you to the "sticky" at the top of the Marine Electronics page here (and I will be adding more to that soon!), and of course to the Sailmail Primer itself...

http://www.cruisersforum.com/forums/...tc-133496.html


This is your cue, John

Thanks,
Bill

I hope this helps...

Fair winds..

John

[ka4wja]

Bill,
In addition to my referring you to the "sticky" up top....
http://www.cruisersforum.com/forums/...tc-133496.html


For details about "proper operating", please see my latest posting there..
http://www.cruisersforum.com/forums/...ml#post2030792

fair winds..

John

[hellosailor]

"Unit has worked for 10 years with no apparent issues other than the Danfoss refrigeration motor controller. Nothing I have tried will shut that thing up other than turning off the breaker."
I had something similar with a Linksys router, which apparently passed FCC tests for home use and then, some engineering accountant removed a few "unneeded" components from the boards before they went on sale. I even put the touer in a cookie tin as a Faraday Cage. No joy, it radiated enough noise on the Ethernet cables to wreak havoc. Choke or no choke, or maybe wrong choke.
But that's actually EMI, no longer RFI since it is traveling on the power cables and not radiating electrically through the aether. In theory, properly matched chokes will stop it. If you know the frequency of the EMI, and if you know the type of choke that absorbs that. Choke materials are vastly different at what frequencies they will eat.

[NahanniV]

I am just getting ready to install my M-802.
I am trying to avoid what the OP has described since I had problems with HF interference on a previous boat.
Already have head unit and speaker installed at nav station.
Insulated back-stay Antenna and grounding are both installed terminating at the stern quarter under the aft cabin bunk (dry area).
I am planning to install the tuner, transceiver, and Pactor modem all in the same area (stern quarter).

The power leads will be about 13' to the battery, not near any other wires.
I have an extension cable for the head unit and speaker;
Those will be the only long cables (approx 30').
The Pactor modem connects by Bluetooth;
I won't be able to see the status lights on the modem.
I am planning to connect the AT-140 to the transceiver using the pig-tails on the AT-140 with a PL259 male-male adapter.

It seems like a good idea to isolate all the HF stuff in one area, but I am wondering if there is some problem I am not aware of ?

Cheers,
JM.

[muttskie]

Originally Posted by ka4wja

Bill,
Okay, here's the short skinny!
It all looks good!
(you're following both the "Sailmail Primer" recommendations as well as those of most/all professional marine SSB installers....and you're looking good!)


Please be sure to read the "sticky" right at the top of the Marine Electronics page here....where you'll find all the references / links to just about everything "marine radio related", including the answers to these questions....(and I'll be adding more to that soon!)
http://www.cruisersforum.com/forums/...tc-133496.html




Here are a few brief specifics, in red....




I hope this helps...

Fair winds..

John

Thank you very much, John.

I did purchase a prefabricated LMR 400 cable that has Amphenol PL 259 connectors installed. I have already installed it, without the need for any difficult bends. I would be willing to remove and replace it with RG 213, if it would be smart to do so.

And thank you for the advice regarding the ferrite cores. I have a bunch of them and will install them as you have described.

I have read all of your stickies, watched all of the videos, and will do so again. Each time I re-read, or re-watch, more is absorbed by my brain and more and more makes sense. It's definitely a learning process.

Thanks again,

Bill Petras

[ka4wja]

Bill,
You're very welcome!
Looks like you're good to go!


As for the LMR-400....sorry about my "rant"...it's just a peeve of mine that so many salesmen push the stuff (high-profit) when another cable is better suited to the application!
But, with a pre-fab cable, already properly installed, you're good...no need to rip it out and run RG-213!

Originally Posted by muttskie

I did purchase a prefabricated LMR 400 cable that has Amphenol PL 259 connectors installed. I have already installed it, without the need for any difficult bends. I would be willing to remove and replace it with RG 213, if it would be smart to do so.

Just hoping others will read this and be advised....

BTW, for HF comms, the loss in the cable is negligible, no matter what cable you choose....and even though I hate generic RG-8x (there are NO standards for this cable, you know), a good quality (Belden) RG-8x or even a nice Belden RG-58 is more than adequate for HF comms, as the loss is negligible....BUT...
But, in our situations (installing coaxial cabling in a boat, in moist areas, in tight spots, etc.), it is the physical strength, outer-jacket integrity, and longevity, of the cabling that are the important factors....
And, here is where a nice RG-213 is your best choice....but, as I write above, a good RG-8x, or even a good RG-58, properly installed, are fine! (heck SGC supplied their tuners with 12' long RG-58 jumpers already attached, for many years....and Icom used RG-58 pig-tails on their AT-140's...)



fair winds...

John

[btrayfors]

Originally Posted by NahanniV

I am just getting ready to install my M-802.
I am trying to avoid what the OP has described since I had problems with HF interference on a previous boat.
Already have head unit and speaker installed at nav station.
Insulated back-stay Antenna and grounding are both installed terminating at the stern quarter under the aft cabin bunk (dry area).
I am planning to install the tuner, transceiver, and Pactor modem all in the same area (stern quarter).

The power leads will be about 13' to the battery, not near any other wires.
I have an extension cable for the head unit and speaker;
Those will be the only long cables (approx 30').
The Pactor modem connects by Bluetooth;
I won't be able to see the status lights on the modem.
I am planning to connect the AT-140 to the transceiver using the pig-tails on the AT-140 with a PL259 male-male adapter.

It seems like a good idea to isolate all the HF stuff in one area, but I am wondering if there is some problem I am not aware of ?

Cheers,
JM.

IMHO, you'd be better served by placing the transceiver nearer to the control head (within 10' or so) and using a longer coax run to the AT-140. Coax can be any desired length, and should be RG8X if you need thin, or RG-213/214 if the 1/2" diameter cable will work for you.

Having the box closer to the control head means you have shorter runs for the power cables, the control head cable, the speaker wire, modem if any, etc. Also makes it easier to install a power/swr meter, either for testing or, better, as a permanent part of the installation.

Bill

[ka4wja]

NahanniV,
I didn't see where Bill, the OP, has any problems to avoid....but, in your case, I see some potential problems (some rather serious), that you can avoid quite easily!

Originally Posted by NahanniV

Insulated back-stay Antenna and grounding are both installed terminating at the stern quarter under the aft cabin bunk (dry area).
I am planning to install the tuner, transceiver, and Pactor modem all in the same area (stern quarter).

First and foremost, installing the transceiver near the antenna is a fairly bad idea...

While the M-802 is a good unit, and well shielded....and if you provide good common-mode isolation (line isolator and plenty of ferrites), and have excellent grounding, this might be okay...BUT...

But, you are asking for trouble placing the radio near the antenna, as you cannot reduce the radiation from the antenna, keeping the radio (transceiver, control head, PACTOR modem, etc.) as far away as possible from the antenna, AND keeping the sensitive wiring (control wiring and modem wiring) going into and out-of the M-802 as short as possible and/or coiled-up thru some ferrites (and NOT long stretched wires, acting as antennas), is the intention you should be designing your installation toward!
And, remember that the AT-140, etc. IS part of your antenna.

(sorry, if that is awkwardly worded....bottom line is: get the radio, modem, etc. away from the antenna and AT-140!)

Running coaxial cable from the radio to the tuner, and keeping then as far away as possible on-board, is your best approach! (and, this is how the system is designed)



Also, I'm not privy to the details of a Finnsailor 38, nor how dry the area you describe is.....but be aware that the AT-140, GTO-15, and a copper-strap ground connection are designed for outdoor/moist/marine environment, and do not technically need a "dry" spot....BUT...
BUT, the M-802 and PACTOR modem, DO need a dry area!!


A few other specifics, in red...

Originally Posted by NahanniV

I am trying to avoid what the OP has described since I had problems with HF interference on a previous boat.
You didn't say whether this was transmit RFI, or received RFI???

Probably the latter (receive RFI), as this is VERY common....and can be caused by oh so much of our modern stuff on-board...
Be advised that most of this (probably 95% to 99%), is noise picked up my your antenna....and only a rare minor amount is "conducted"....meaning that there is little to do on the HF radio itself, to eliminate this...
BUT, you can do a LOT by eliminating this RFI from being radiated by all the stuff on-board!! (see references/links in the "sticky" at the top of the Marine Electronics page, for lots of details here!)
http://www.cruisersforum.com/forums/...tc-133496.html


As for transmit RFI....you are setting yourself up for troubles here, if you're placing the radio, modem, etc. near the AT-140 and antenna!



Already have head unit and speaker installed at nav station.
Insulated back-stay Antenna and grounding are both installed terminating at the stern quarter under the aft cabin bunk (dry area).
Don't know what "grounding" you have already installed, but as an FYI, much of the transmit RFI (where your transmit signal interferes with other systems on-board) can be reduced by:
--- proper grounding of the remote tuner (preferably a low-impedance direct sea water connection)
--- lots of ferrites on the wiring of these other systems...(impossible to protect everything, of course...which is why having a direct sea water RF Antenna Ground can be a VERY important thing!)



I am planning to install the tuner, transceiver, and Pactor modem all in the same area (stern quarter).
As for transmit RFI....you are setting yourself up for troubles here, if you're placing the radio, modem, etc. near the AT-140 and antenna!


The power leads will be about 13' to the battery, not near any other wires.
If you are running the DC power wiring (larger than the Icom-supplied wiring) directly to the batteries, doubtful that having near any other wires would be of any issue...




I have an extension cable for the head unit and speaker;
Those will be the only long cables (approx 30').
The Pactor modem connects by Bluetooth;
I won't be able to see the status lights on the modem.
I am planning to connect the AT-140 to the transceiver using the pig-tails on the AT-140 with a PL259 male-male adapter.

These here underlined above, are rather bad ideas...see above for details...
Nothing wrong with Bluetooth for laptop-to-modem connection, but placing the radio near the antenna and antenna tuner, and running long control wires, are both very bad ideas!!!!


It seems like a good idea to isolate all the HF stuff in one area,
Why would that seem like a good idea??
For proper operation, testing, etc. as well as for RFI reasons, you want to keep your radio and as much of your electronics equipment away from the radiating antennas...
And, in general, it's easiest to have as much of your electronics gear centrally located...
So, it is actually a rather bad idea to place the radio, modem, etc. next to the tuner and antenna!

but I am wondering if there is some problem I am not aware of ?
Yes, please read all of the above....
And, please read the "sticky" at the top of the Marine Electronics page...
http://www.cruisersforum.com/forums/...tc-133496.html

Cheers,
JM.

I hope this helps..

Fair winds..

John

[NahanniV]

@btrayfors
@ka4wja

Thanks for your replies, glad I asked.

I will have to find a spot for the transceiver further from the antenna and tuner.

How important is a line isolator ? Grounded or not ?

Cheers,
JM.

[exMaggieDrum]

Since refrigeration compressors/motors are such a common problem, what can be done to shield that? I put a perforated copper "shield" over one on my last boat but not sure it really helped that much. Would ferrites on the power wires to the unit help?