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SSB Noise Elimimation

SSB interferance

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#1 B.J. Porter

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Posted 15 October 2012 - 02:03 PM

Sadly, I think I said one of the magic words...if he shows we can just ignore him.

As mentioned in another thread, I'm having some noise issues with my SSB particularly around 8Mhz which is were a few of the more popular cruising nets are located.

I did the "shutdown" test, but I need to give some brief over view of the current installation and what I plan to do before I get into details. Many of you know I've got 24V House primary power and 12V house for radios and such. So "shutting down the boat" without killing the radio isn't such a big deal since I can turn off 99% of the boat without messing with the 12V though here are a couple of things on the 12V house.

This morning, listening to the Cruiseheimer's on 8152 Mhz with (almost) all the 24V systems powered off with the main battery switch thrown I could hear pretty well for a change, in the past I've not heard much at all. Picked up checkins from Fisher's Island to Delray Beach, Florida (currently sitting in Oxford, MD myself). I didn't disconnect the 24V battery wire so there were a couple of things still on, potentially noisy - 110 inverter on standby and the battery monitor, most notably. Those might add noise, but it worked pretty well with them on.

Then I started turning things on slowly and in an isolated fashion and started find some noise makers.

They were:
- Spectra water maker; even when it's not making water the control panel is on all the time, ticking down to the next membrane flush.
- NMEA 2000 instruments. This is the big one, I don't think I can leave my instruments off for hours to get weather faxes and so on.
- Fridge/Freezer. The compressors seem to make more cyclic noise than the water pump, this is a Frigoboat raw water cooled system.
- A 12V volt circuit called "Lights 2" which I need to explore what is on that.

Surprisingly a few things did not cause extreme noise including:
- Blue Sky 3024i solar charge controller, though it IS kind of cloudy this AM
- Ship's PC
- Wind generator in 10-12 knots of wind

I found enough noise with the N2K to not even bother firing up all the Furuno hardware (MFD's, Radar, AIS, Autopilot, etc.) which I probably should do.

My NMEA power source is encrusted with the ferrites that one of you guys recommended in another SSB thread. The N2K network has a LOT of stuff on it, so I'm a little nonplussed where else to start looking. One maybe culprit is the NMEA 0183 IN to the radio, which is done with an Actisense N2K to 0183 bridge being send through one of their NMEA buffers; I will apply ferrites but I don't think that's will solve it.

I've got one closet behind my nav station I turned into a comm/tech closet - there's a lot of gear in there including my PC, the power supply for the Radar, the AIS receiver (no transceiver...don't ask), as well as three of those Actisense N2K converters and the NMEA Buffer. I wonder if there is some way to shield the whole comm closet somehow.

What I am planning to do:

My first step here is to rewire the power on the SSB - it's not optimal. When I installed the new SSB I used the existing power feed which is a run of 8AWG. This goes back to the main 12V house feed fuse (not through the main power switch) which goes to the batter, and the Negative goes to a ground shunt for a now removed battery monitor that goes to a common ground. I've gotten some 6 AWG double wire which I intend to run directly back to the house battery, getting it off the common ground and directly on the batter with appropriate fusing. At a minimum it should insure that the power is a clear as it could be and I'm not getting any warbling.

What I need to figure out:
- How to stop the N2K noise. I can't leave my N2K instruments off for hours when I am say, receiving Weather faxes. Even shutting them down for a short while is a pain in the rear as it sets off all sorts of alarms, the boat loses heading information, etc. etc.

- How to minimize the howl from the fridge/freezer. I can shut them off for a while for net check-ins and communication but the fax thing needs to happen (no, I don't have a sat phone and no plans to get one).

- The water maker noise; I will contact Spectra about this but I will also slap a few ferrites around and see what happens. The question is where to stick them. The Catalina 200 with the MPC-5000 controller stays on all the time, every 120 hours it kicks off a cycle that does a freshwater wash on the membrane. This is in lieu of pickling it when you don't use it for an extended period. In theory I could turn it off and set an alarm every five days but if I forget I could ruin the membrane which is ex$pen$ive. Right now we're not using but when we get to the Caribbean in a couple of weeks this will change.

- "Lights 2"; I need to run this circuit down and see whats on it.


So - suggestions, guidance, help and all the usual?? I wish there was a device I could just wave over my electronics to detect and analyze noise.

#2 sailSAK

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Posted 15 October 2012 - 02:31 PM

I should be paying more attention to these threads. I couldn't even hear the high seas voice forecast without shutting down at least the engine, heater, refer, and autopilot. It was inconvenience enough that I abandoned my plans to join the pacsea net. My only thought was to put the radio and tuner on its own dedicated battery that was completely isolated when working the radio. SSB counterpoise would be through my dynaplate and copper foil only without a tie to the boat's DC negative. Easy enough to try, but that would suck if you are using it for pactor, wefax and such.

#3 B.J. Porter

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Posted 15 October 2012 - 02:35 PM

I should be paying more attention to these threads. I couldn't even hear the high seas voice forecast without shutting down at least the engine, heater, refer, and autopilot. It was inconvenience enough that I abandoned my plans to join the pacsea net. My only thought was to put the radio and tuner on its own dedicated battery that was completely isolated when working the radio. SSB counterpoise would be through my dynaplate and copper foil only without a tie to the boat's DC negative. Easy enough to try, but that would suck if you are using it for pactor, wefax and such.


My pactor powers off the radio itself so that wouldn't be a problem. I'm using a KISS SSB for a counterpoise which seems to work reasonably well - on other bands people can hear me.

#4 kent_island_sailor

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Posted 15 October 2012 - 02:37 PM

Lights is likely an LED light. Most of mine make no noise at all and one or two really mess up the SSB :(
As far as a device to "wave", we used to use old cheap AM radios. You can do some creativeve foil wrapping to make it less sensitive.
As much as I hate to even mention it, an o-silly-scope can actually help in some cases :rolleyes:
You might want to do more ferrites on the N2K stuff. Every lead right off the instrument and use more then you think you need. Also try a direct run from SSB to battery and ferrite those leads too. I used to carry bags of the things to my jobs.

#5 B.J. Porter

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Posted 15 October 2012 - 02:48 PM

Lights is likely an LED light. Most of mine make no noise at all and one or two really mess up the SSB :(
As far as a device to "wave", we used to use old cheap AM radios. You can do some creativeve foil wrapping to make it less sensitive.
As much as I hate to even mention it, an o-silly-scope can actually help in some cases :rolleyes:
You might want to do more ferrites on the N2K stuff. Every lead right off the instrument and use more then you think you need. Also try a direct run from SSB to battery and ferrite those leads too. I used to carry bags of the things to my jobs.


"I think we're going to need a bigger ferrite"

I've been sprinkling these and these all over the boat. I need more, I've put quite a lot of them around but not on each instrument.

Getting stuff shipped now is SUCH a pain...

#6 kent_island_sailor

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Posted 15 October 2012 - 03:33 PM

How long are you around for?
I am going to Florida Weds and back Sunday. You can ship stuff to my house and I can drive it to Oxford or nearby areas.


Lights is likely an LED light. Most of mine make no noise at all and one or two really mess up the SSB :(
As far as a device to "wave", we used to use old cheap AM radios. You can do some creativeve foil wrapping to make it less sensitive.
As much as I hate to even mention it, an o-silly-scope can actually help in some cases :rolleyes:
You might want to do more ferrites on the N2K stuff. Every lead right off the instrument and use more then you think you need. Also try a direct run from SSB to battery and ferrite those leads too. I used to carry bags of the things to my jobs.


"I think we're going to need a bigger ferrite"

I've been sprinkling these and theseall over the boat. I need more, I've put quite a lot of them around but not on each instrument.

Getting stuff shipped now is SUCH a pain...



#7 VALIS

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Posted 15 October 2012 - 03:38 PM

Good idea on the AM radio as a sniffer, but if the interference is truly localized around 8 MHz the AM radio might not hear it. If you can get an all-band receiver, try that. You might be able to use the SSB receiver as a sniffer: Make up a length of coax with a small single-turn hairpin coil (about one inch in diameter) from the center conductor to the shield at one end, and an appropriate connector at the other. Use RG-58, or some other flexible cable. Disconnect the antenna / tuner coax from your SSB, and connect this sniffer cable.

How to use the sniffer: Before you start, characterise the noise you are searching for. Is it a broadband hash, or is it a discrete frequency? Try to tune it in, searching for the strongest interfering signal. If, for example, you hear a strong signal at 8.000 MHz, search at 4.000, 2.666, 2.000, 1.600 MHz, etc (these are 8/2, 8/3, 8/4, 8/5 -- the interfering signal may be lower in frequency, with 8 MHz as a harmonic). Turn stuff off and on while you are listening for the interference.

Having found a strong interfering signal, use the sniffer and poke around your instruments, etc. There may be one particular device on your N2K string that is particularly noisy. It's possible that multiple devices are contributing, but it's often the case that you have one major culprit.

But before you start the sniffing project, do continue with the process of disconnecting and powering-down individual devices. This is usually the easiest way to localize the problem.

Another test: Tuen the SSB to the offending frequency, then disconnect your antenna cable from the radio. If the interference persists, it may be conducted via your power and control cabling. This will be easier to fix (use more ferrites, and possibly capacitors).

Before you even consider shielding your nav-equipment locker (which will be a lot of work, and probably ineffective) do locate the source of interference.

Regarding the refrigerator, try searching "SSCA Forum". People have posted there with their refrigerator controller shielding / filtering efforts. Here's a link to one of these conversations: http://forum.ssca.or...php?f=5&t=12779

#8 Innocent Bystander

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Posted 15 October 2012 - 04:27 PM

How long are you around for?
I am going to Florida Weds and back Sunday. You can ship stuff to my house and I can drive it to Oxford or nearby areas.



Lights is likely an LED light. Most of mine make no noise at all and one or two really mess up the SSB :(
As far as a device to "wave", we used to use old cheap AM radios. You can do some creativeve foil wrapping to make it less sensitive.
As much as I hate to even mention it, an o-silly-scope can actually help in some cases :rolleyes:
You might want to do more ferrites on the N2K stuff. Every lead right off the instrument and use more then you think you need. Also try a direct run from SSB to battery and ferrite those leads too. I used to carry bags of the things to my jobs.


"I think we're going to need a bigger ferrite"

I've been sprinkling these and theseall over the boat. I need more, I've put quite a lot of them around but not on each instrument.

Getting stuff shipped now is SUCH a pain...


Same for the Western Shore. If you will be in the Solomons area, ship it to me and I'll deliver. I'll be in NY Wed-Friday but otherwise here.

#9 B.J. Porter

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Posted 15 October 2012 - 04:47 PM


How long are you around for?
I am going to Florida Weds and back Sunday. You can ship stuff to my house and I can drive it to Oxford or nearby areas.



Lights is likely an LED light. Most of mine make no noise at all and one or two really mess up the SSB :(
As far as a device to "wave", we used to use old cheap AM radios. You can do some creativeve foil wrapping to make it less sensitive.
As much as I hate to even mention it, an o-silly-scope can actually help in some cases :rolleyes:
You might want to do more ferrites on the N2K stuff. Every lead right off the instrument and use more then you think you need. Also try a direct run from SSB to battery and ferrite those leads too. I used to carry bags of the things to my jobs.


"I think we're going to need a bigger ferrite"

I've been sprinkling these and theseall over the boat. I need more, I've put quite a lot of them around but not on each instrument.

Getting stuff shipped now is SUCH a pain...


Same for the Western Shore. If you will be in the Solomons area, ship it to me and I'll deliver. I'll be in NY Wed-Friday but otherwise here.


Thanks guys! We're headed into the Hinckley yard this afternoon to get the seal on the timing cover on the generator replaced, should take a couple of days.

After that we've not figured out where to go. Need to be in Hampton around Halloween or a little before to start our last prep to go to the Caribbean.

#10 kent_island_sailor

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Posted 15 October 2012 - 05:07 PM

I have noticed that HF radio in general has been noisy with utter crap propagation for a long time now. I seem to have many days when it seems wall to wall noise. It seems to just now be getting a few sunspots and picking back up.
We should set up a SSB schedule. Do you do PSK31?
I'll have my boat back in her slip by November.
More noise :(
No wading out to the dinghy to go to the mooring though :) *

*really odd zoning rule for our club means a powered dinghy has to floating out OFF the beach

#11 B.J. Porter

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Posted 15 October 2012 - 05:14 PM

I have noticed that HF radio in general has been noisy with utter crap propagation for a long time now. I seem to have many days when it seems wall to wall noise. It seems to just now be getting a few sunspots and picking back up.
We should set up a SSB schedule. Do you do PSK31?
I'll have my boat back in her slip by November.
More noise :(
No wading out to the dinghy to go to the mooring though :) *

*really odd zoning rule for our club means a powered dinghy has to floating out OFF the beach


I've never tried PSK.

#12 kent_island_sailor

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Posted 15 October 2012 - 05:27 PM

I love PSK31. *No Sound*
After everyone is in their bunks I crank it up and "talk" silently. It gets through when conditions are bad way better than voice.


I have noticed that HF radio in general has been noisy with utter crap propagation for a long time now. I seem to have many days when it seems wall to wall noise. It seems to just now be getting a few sunspots and picking back up.
We should set up a SSB schedule. Do you do PSK31?
I'll have my boat back in her slip by November.
More noise :(
No wading out to the dinghy to go to the mooring though :) *

*really odd zoning rule for our club means a powered dinghy has to floating out OFF the beach


I've never tried PSK.



#13 Timo42

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Posted 15 October 2012 - 06:40 PM

I love PSK31. *No Sound*
After everyone is in their bunks I crank it up and "talk" silently. It gets through when conditions are bad way better than voice.



I have noticed that HF radio in general has been noisy with utter crap propagation for a long time now. I seem to have many days when it seems wall to wall noise. It seems to just now be getting a few sunspots and picking back up.
We should set up a SSB schedule. Do you do PSK31?
I'll have my boat back in her slip by November.
More noise :(
No wading out to the dinghy to go to the mooring though :) *

*really odd zoning rule for our club means a powered dinghy has to floating out OFF the beach


I've never tried PSK.

As long as some Winlid doesn't start pactorbating <_< without checking for a clear frequency, psk31 is great :ph34r: , info Digipan software. and the waterfall display is cool looking. :P

#14 B.J. Porter

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Posted 15 October 2012 - 07:36 PM


I love PSK31. *No Sound*
After everyone is in their bunks I crank it up and "talk" silently. It gets through when conditions are bad way better than voice.



I have noticed that HF radio in general has been noisy with utter crap propagation for a long time now. I seem to have many days when it seems wall to wall noise. It seems to just now be getting a few sunspots and picking back up.
We should set up a SSB schedule. Do you do PSK31?
I'll have my boat back in her slip by November.
More noise :(
No wading out to the dinghy to go to the mooring though :) *

*really odd zoning rule for our club means a powered dinghy has to floating out OFF the beach


I've never tried PSK.

As long as some Winlid doesn't start pactorbating <_< without checking for a clear frequency, psk31 is great :ph34r: , info Digipan software. and the waterfall display is cool looking. :P


Better go dig up that ARRL guide to HF communications. Sounds more like Hammy rag-chewing stuff than practical cruiser things!

#15 phantomsailor

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Posted 16 October 2012 - 06:13 PM

Not sure what kind of reefer compressors you have but Danfoss compressor controllers are notorious for SSB interference. Danfoss makes a shielded version of their compressor controller - for a BD35, the controller is a 101N0320. Haven't tried one myself as the controllers are spendy.

I have a freezer and a reefer with a BD-35 for each. With either compressor running, it literally wipes out the 40 meter ham band and the 8 Mhz marine band. The interference sounds like crappy unreadable morse code that slowly drifts up or down in frequency. I just shut the reefer and freezer off when using the SSB. Problem is, I forget to turn them back on.

#16 Zonker

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Posted 18 October 2012 - 03:44 AM

+1 on the fridge. We routinely shut ours off when talking on ham/ssb or doing Pactor. Yes we listen before sending. Well I do, my wife hits the green button with the volume down...

#17 B.J. Porter

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Posted 18 October 2012 - 12:03 PM

Well the helpful fellow from Spectra Watermakers wrote that I should "Make sure that all of the control cables for the both the MPC 5000 control board, and the remote display are run on opposite sides of the vessel from each other, and that at no point do they ever run next to, or parallel to each other."

Which may be challenging once everything is freaking installed on the boat.

The SSB is on the opposite side of the boat from the watermaker, and the cables only come close near the nav station .

#18 B.J. Porter

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Posted 18 October 2012 - 04:33 PM

So I put a PEP/SWR meter on the radio.

The good news is my antenna SWR is around 1.2.

The bad news is that my PEP transmitting on the 40 M & 20M bands was around 15 Watts. That ain't right at all, although it DOES explain why I could hear net checkins from New England to FL, but someone in Annapolis had to relay my check in to the net control.

Planning to re-wire the power to get good, clean, properly crimped connections direct to the house battery then re-test.

#19 VALIS

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Posted 18 October 2012 - 04:38 PM

Hey may have said "opposite sides of the boat", but what this really means is "don't bundle the cables together". As long as you have a couple of inches between the cables (on average) there should be no problem, and having them occasionally be close should also not cause issues.

I say this because if the cable and signals are so sensitive to external coupling that a spacing of a few inches causes problems, then the system just isn't going to work with any reasonable length of cable regardless of how the cables are routed. I have a Spectra watermaker with the controller and remote display, the cables are probably 20 feet long, and as I recall they are run along the same general path. It works fine.

This doesn't mean that the watermaker cables won't generate SSB interference. If so, ferrites at each end should help. I usually keep the watermaker powered off, and I don't recall if mine generates any EMI.

#20 Timo42

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Posted 18 October 2012 - 04:44 PM

So I put a PEP/SWR meter on the radio.

The good news is my antenna SWR is around 1.2.

The bad news is that my PEP transmitting on the 40 M & 20M bands was around 15 Watts. That ain't right at all, although it DOES explain why I could hear net checkins from New England to FL, but someone in Annapolis had to relay my check in to the net control.

Planning to re-wire the power to get good, clean, properly crimped connections direct to the house battery then re-test.


Have you checked the voltage at the radio while transmitting? Would shielding the battery cables to the radio help maybe?

#21 VALIS

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Posted 18 October 2012 - 04:48 PM

So I put a PEP/SWR meter on the radio.

The good news is my antenna SWR is around 1.2.

The bad news is that my PEP transmitting on the 40 M & 20M bands was around 15 Watts. That ain't right at all, although it DOES explain why I could hear net checkins from New England to FL, but someone in Annapolis had to relay my check in to the net control.

Planning to re-wire the power to get good, clean, properly crimped connections direct to the house battery then re-test.


Remind me: What radio do you have? The low power output may be due to mic gain / compressor settings. Also, what SWR meter are you using?

I'm available for ham and marine band contacts for the next few days. I've got an Icom IC-7200 and a multi-band off-center dipole here at the Friday Harbor house, and my boat (with the Icom 710 and backstay antenna) is in the marina.

#22 B.J. Porter

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Posted 18 October 2012 - 05:10 PM


So I put a PEP/SWR meter on the radio.

The good news is my antenna SWR is around 1.2.

The bad news is that my PEP transmitting on the 40 M & 20M bands was around 15 Watts. That ain't right at all, although it DOES explain why I could hear net checkins from New England to FL, but someone in Annapolis had to relay my check in to the net control.

Planning to re-wire the power to get good, clean, properly crimped connections direct to the house battery then re-test.


Remind me: What radio do you have? The low power output may be due to mic gain / compressor settings. Also, what SWR meter are you using?

I'm available for ham and marine band contacts for the next few days. I've got an Icom IC-7200 and a multi-band off-center dipole here at the Friday Harbor house, and my boat (with the Icom 710 and backstay antenna) is in the marina.


Icom IC-M802 radio, Daiwa CN-101L meter. I know it's a low end meter, but +/- 10% accuracy is close enough for what I'm talking about.

I'll be replacing the battery source cables in the next 24 hours or so, then we can test a little more.

#23 VALIS

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Posted 18 October 2012 - 06:05 PM

I've got the Daiwa CN-101L sitting on top of the ham rig here. As an experiment (testing as I type this), I hooked it up in series with an MFJ-872 SWR/Power meter, and then on to a dummy load. The MFJ is another hobbyist-grade meter, that claims to work to 200 MHz, so I use it for testing marine VHF connections. When compared to the MFJ, the Daiwa often reads low when measuring PEP. When I transmit full-power in RTTY mode (I would use CW but I don't have my key here), the two meters both read about 105W. On USB, when I whistle into the mic they both read about 100-110W. When I say "test" (actually, "teeeeeessst") the Daiwa reads about 50W and the MFJ reads 100W. I don't have my spectrum analyzer here, but I do recall doing this same test and seeing that the radio was putting out full peak power, so I think the Daiwa under-reports PEP with some voices.

Still, it should be showing you more than 15W.

When you were transmitting and being relayed, did the relay station comment on your signal quality? If you've got a poor 12V supply, this will usually cause serious distortion on your transmitted signal. If you were sounding clean, it's not likely that you have DC power issues.

The 802 did originally have issues with overload and compression. Do you know the history of your particular radio? Ones that are fairly new (or had the factory modifications) should be OK.

#24 Moonduster

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Posted 18 October 2012 - 09:54 PM

I have never been on a cruising boat that had voice communications over SSB without some degree of interference from onboard electronics.

The random conducted interference from a few dozen systems, even in stand by, quickly becomes unmanageable. Clamp-on chokes might help a bit, but even with real toroids, you're fighting an uphill battle. To a great extent, one's success is a matter of luck. Beyond that, good installation practices can help. But in many cases, the only viable solution is to switch off the offending components.


From my experience, the likelihood of even moderate voice communication over an SSB radio while brushed DC motors (water makers, refrigeration, pressure water, etc) or alternators or gensets is zero. These things are sources of radiated, not conducted, emissions and no number of chokes will suppress the noise.

#25 VALIS

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Posted 18 October 2012 - 10:21 PM

From my experience, the likelihood of even moderate voice communication over an SSB radio while brushed DC motors (water makers, refrigeration, pressure water, etc) or alternators or gensets is zero. These things are sources of radiated, not conducted, emissions and no number of chokes will suppress the noise.


Brushed motors are definitely noisemakers, but I think the odds are better than zero. For example, during the Pac Cup and return passages VALIS was the comms boat. We had our refrigerator always powered (a 12V Danfoss system), and I guarantee you that the motor would occasionally be spinning during our net operations on 4, or 6, or 8 MHz. For whatever reason I've had no problems with motor-related noise on receive. My NMEA-0183 system does put out some one-second pulses that I can hear weakly on some channels. but other than that VALIS is a pretty quiet boat. I haven't tried running the watermaker, windlass, etc, during SSB operations. I've taken no heroic EMI-suppression efforts, other than a liberal use of ferrites.

Oh yeah, I almost forgot: Running the engine during SSB operations is bad. The alternator and charging system put out a lot of noise.

#26 Naviguesser

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Posted 02 November 2012 - 03:41 AM

It's a very good idea to identify all of your various noise sources so that when you're in the middle of nowhere trying to receive a weak signal you can turn off the offending noise sources rather than troubleshoot the problem on the water. We had to shut down the Ockam instruments to receive Gribs and weather faxes during the '08 Pac Cup; chokes made little difference, if any.

#27 NoStrings

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Posted 02 November 2012 - 08:25 AM

Oddly enough it wasn't my alternator that raised the noise floor, it was the reefer pump that we turned on around day 10. We also accidentally disconnected the tuner control cable around day 12 while we were wrestling with the quadrant. On the way home we ran the reefer 24/7, but we had to turn it off to transmit. Chokes had no effect at all.

#28 kent_island_sailor

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Posted 02 November 2012 - 11:19 AM

That Icom model is somewhat famous for backing power WAY off if the SWR isn't perfect. If memory serves, there is a fix for it.
Experiment - get a dummy load and see what happens. If you can't find a real one, connect some coax to a light bulb. A 50 watt bulb should get pretty bright on the voice peaks. Does that radio have a CW key connection so you can get the full 150 watts for testing?

http://www.hamradio....m?pid=H0-001070

#29 B.J. Porter

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Posted 02 November 2012 - 12:09 PM

That Icom model is somewhat famous for backing power WAY off if the SWR isn't perfect. If memory serves, there is a fix for it.
Experiment - get a dummy load and see what happens. If you can't find a real one, connect some coax to a light bulb. A 50 watt bulb should get pretty bright on the voice peaks. Does that radio have a CW key connection so you can get the full 150 watts for testing?

http://www.hamradio....m?pid=H0-001070


If I shut off the water maker, N2K net, and refigeration I can hear people from Maine to Florida and still be heard.

I'll be distributing ferrites all over the N2K net, but I just got word we're leaving Sunday now, which is a change from the initial postponement to Tuesday. So not a lot of time to screw around.

I think I might just tie in one of my handheld Garmins to the Navnet MFD so I can kill N2K for communications without losing position information.

#30 Innocent Bystander

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Posted 02 November 2012 - 01:46 PM


That Icom model is somewhat famous for backing power WAY off if the SWR isn't perfect. If memory serves, there is a fix for it.
Experiment - get a dummy load and see what happens. If you can't find a real one, connect some coax to a light bulb. A 50 watt bulb should get pretty bright on the voice peaks. Does that radio have a CW key connection so you can get the full 150 watts for testing?

http://www.hamradio....m?pid=H0-001070


If I shut off the water maker, N2K net, and refigeration I can hear people from Maine to Florida and still be heard.

I'll be distributing ferrites all over the N2K net, but I just got word we're leaving Sunday now, which is a change from the initial postponement to Tuesday. So not a lot of time to screw around.

I think I might just tie in one of my handheld Garmins to the Navnet MFD so I can kill N2K for communications without losing position information.


BJ,

Good luck on the rally. We'll expect position reports and observations as you go.

Best to the family.

L&L.

#31 B.J. Porter

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Posted 02 November 2012 - 05:14 PM



That Icom model is somewhat famous for backing power WAY off if the SWR isn't perfect. If memory serves, there is a fix for it.
Experiment - get a dummy load and see what happens. If you can't find a real one, connect some coax to a light bulb. A 50 watt bulb should get pretty bright on the voice peaks. Does that radio have a CW key connection so you can get the full 150 watts for testing?

http://www.hamradio....m?pid=H0-001070


If I shut off the water maker, N2K net, and refigeration I can hear people from Maine to Florida and still be heard.

I'll be distributing ferrites all over the N2K net, but I just got word we're leaving Sunday now, which is a change from the initial postponement to Tuesday. So not a lot of time to screw around.

I think I might just tie in one of my handheld Garmins to the Navnet MFD so I can kill N2K for communications without losing position information.


BJ,

Good luck on the rally. We'll expect position reports and observations as you go.

Best to the family.

L&L.


Date is back to Thursday-ish depending on weather window.

I won't be able to update here on SA, but I can send e-mails and will be updating the blog.

via Winlink

#32 kent_island_sailor

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Posted 02 November 2012 - 08:12 PM

Pick one of us and we'll translate email to CA ;)

A few of us could do a ham schedule too if you want.

#33 B.J. Porter

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Posted 02 November 2012 - 08:30 PM

Pick one of us and we'll translate email to CA ;)

A few of us could do a ham schedule too if you want.


The rally will be checking in with the Doo-dah net (1700 EST, 8152 Mhz) every day as well.





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