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Critter
03-11-2010, 11:46 AM
With profuse thanks to Scott Prusso, I have the use of an Icom M700 Pro and AT-130 tuner for the SHTP. I've emailed Scott the following question, but he's out on the ocean somewhere.

There's a 4-conductor control cable that runs between the radio and tuner, and I have to connect the four wires to terminals inside the tuner box. The Icom manual has a little schematic of the connector at the radio end of the cable, on which the four conductors are identified, but it's not clear to me whether the labels apply when I'm looking at the front or the back of the connector (and which connector, M or F).

The four conductors are labeled:
Key
Start
13.6
E

Can I assume that the red wire is 13.6, ie positive power? That's one of the two possible interpretations of the diagram.

TIA ... Max

Culebra
03-11-2010, 12:35 PM
Max, I don't know the answer to your question, but be sure to go to this Sailnet thread and check out the wealth of basic information there. Also check a PM from me. One thing very interesting... it is recommended not to connect the tuner ground lug (with the wing nut) to anything, and not to connect the radio ground terminal to anything. Obviously do connect the power + and - terminals, but not the third one designated as ground. This is (they say) a common source of very bad interference with other boat systems.

http://www.sailnet.com/forums/electronics/60390-ssb-installation.html

Paul
Culebra

Culebra
03-11-2010, 12:51 PM
I should correct something I said... obviously you have to connect your antenna ground or counterpoise to the tuner ground lug. The important thing (they say) is not to connect that ground to your boat systems, not the engine especially, since that is tied into the negative side of the batteries and house panel. No copper foil connecting the tuner to the engine... a no-no. That gound should be completely independent of all other boat systems. And again, the radio ground terminal should connect to nothing (even though the ICOM manual says to connect it).

Paul
Culebra

BobJ
03-11-2010, 01:09 PM
Max, it looks like the answer may be in here:

http://www.icomamerica.com/en/downloads/Default.aspx?Category=137


Paul, Don at HF Radio says the same thing about not connecting the radio's ground.

However I did run a second copper foil from the tuner to the engine when the foil from the tuner to the keel bolt proved insufficient, so I can't agree on that one.

SSB counterpoises are all voodoo science anyway.

Culebra
03-11-2010, 05:47 PM
SSB counterpoises are all voodoo science anyway.

For a fun read on the voodoo science of radials and counterpoise (well... depends on a person's idea of fun), check out this article:

http://www.antennex.com/shack/Dec06/cps.html

Paul
Culebra

BobJ
03-11-2010, 06:03 PM
That guy cannot possibly have a life.

jfoster
03-12-2010, 12:24 PM
That guy cannot possibly have a life.

You are right, he died in 2008. However, a very active memorial site

http://cebik.com/

with mailing list forums lives on. There you can find more than you ever wanted to know about a world of antenna enthusiasts. I am a subscriber to their mailing list. Why?

My first diploma (from Ryerson in Toronto) in 1958 left me anomalously proficient with a large circular slide rule dedicate to antenna and antenna feed line calculations. Fifty something years ago does not seem all that long to be interested in something. After all, I bought my first cat rigged boat sixty three years ago. (grin)

John
Blueberry, Nonsuch 22 sail # 48

glythcott
04-08-2010, 11:49 AM
I am thinking of buying an ICOM 710 SSB on eBay. Does anyone know this unit? Will it do the trick (assuming it is in good working condition)?

Oceanslogic
04-21-2010, 10:30 AM
Hello everyone...
I pretty much have my SSB set up...and have the area where I will install the tuner...but I was wondering if it mattered if the tuner was mounted vertically (like on a bulkhead) or horizontally??? I would prefer to mount it vertically....Thanks for any help or info on this matter...

Adam
s/v Blue Moon
International Folkboat #175

BobJ
04-21-2010, 11:21 AM
My AT-140 is mounted horizontally on the inside wall of the cockpit. I don't think orientation matters as long as the tuner is as close as possible to the antenna.

I have a line (RFI) isolator in the tuner-to-radio control cable, at the tuner end, and two ferrite chokes in the cable at the radio end. Also try to keep the control cable away from your autopilot cables, if applicable. It avoids the "key the mike to gybe the boat" scenario.

Alchera
04-21-2010, 01:50 PM
Hello everyone...
I pretty much have my SSB set up...and have the area where I will install the tuner...but I was wondering if it mattered if the tuner was mounted vertically (like on a bulkhead) or horizontally??? I would prefer to mount it vertically....Thanks for any help or info on this matter...

Adam
s/v Blue Moon
International Folkboat #175

Check to see if the cooling vents are set up to use natural convection or a cooling fan. If you have a fan, the orientation probably doesn't matter that much. If it relies on convection only, then make sure the orientation allows the air to flow naturally from low to high through the unit.

- Mark

Samuel Burns
04-22-2010, 02:00 PM
Hello everyone...
I pretty much have my SSB set up...and have the area where I will install the tuner...but I was wondering if it mattered if the tuner was mounted vertically (like on a bulkhead) or horizontally??? I would prefer to mount it vertically....Thanks for any help or info on this matter...

Adam
s/v Blue Moon
International Folkboat #175

BobJ email above dated 3-11-10 has a link to AT-130 tuner PDF download, p.4 "mounting instructions" state either horizontal or vertical mounting with one of the water drains facing downwards.....Sam S 'aire......

glythcott
05-16-2010, 10:02 PM
I recently (today) finished my SSB installation and need to test it. In addition, I have no clue how to operate this radio. Is there a SSB person who can walk me through it and who I can attempt to talk with (on the radio)?

Critter
05-17-2010, 09:12 AM
George, I'd also like to do a test call. I think Eva of Fri is interested too. Sunday afternoon would be my first opportunity. Anybody else?

I doubt I can help you with operating the thing, other than "turn it on and twist the dial until you see a frequency that you recognize". Try Brian Boschma, he's given me some good advice.

Max

tiger beetle
05-17-2010, 09:29 AM
Tiger Beetle is available most evenings for an SSB radio check; I would be in the slip, so communications are not that good as compared to being out in the bay (marina has lots of RF noise and adjacent masts soak up the broadcast signal).

Let me know (via phone or email) if there's a convenient evening to try out the radio. I'm using an Icom M802, and won't know much about operating other radios. Simple thing to do is bring up WWV to see how the tuner and receiver are working.

- rob/beetle

cafemontaigne
05-17-2010, 10:31 AM
I am available evenings as well, but the surrounding terrain might make it hard to reach as far as California. I'd like to give it a try though. Later in the evening is probably better for propagation. I can be on the air on Sunday afternoon, and I'll probably be out in the open sailing as well.

I definitely heard Fri last time.

Adrian
Idefix

Paul Elliott
05-17-2010, 01:27 PM
VALIS will be at sea May 30-31 (Sunday-Monday) as we return home from the Spinnaker Cup, and I would be happy to help with a radio check. I might be able to do one during the race (Fri-Sat), depending on how hectic things are.

John Hayward
05-23-2010, 11:49 AM
I recently (today) finished my SSB installation and need to test it. In addition, I have no clue how to operate this radio. Is there a SSB person who can walk me through it and who I can attempt to talk with (on the radio)?

George,

I am just getting caught up on the forum. I just bought a 710 and I think most everything you need to know is in the manual which is available on line if you got a used radio and it didn't come with it. If you haven't gotten help already and you have specific questions, I would be happy to try to help. You already have my email address. I can also participate in radio checks if I know when and where.

John H
Dream Chaser