You are all very welcome....
For Mike, and anyone else planning an
HF radio install on-board (whether M-802 or otherwise)...
Quote:
Originally Posted by Mike OReilly
I'll be getting into an install project over the next six months. Hope I won't need to pester CFers too much for help .
|
...I have a few tips / pieces of
advice for you all...
Here are a few of the most important things to do (and/or not do), that are often ignored by many doing their own installs....
Enjoy...
1)
Power the radio (12vdc) directly from your main house
battery bank, do NOT go thru a distribution panel / breaker panel....and I further recommend not even thru a vessel's DC buss bars, but directly to the
batteries...
Do NOT use the entire length of DC
power wire supplied with the radio, as it is designed for installations were there is a constant 13.8vdc available (not our nominal/typical 12.5vdc)....
I recommend using the last 12" - 18" max. of this supplied power cable, typically near where there will be fuse(s), and then use a much larger wire run direct to your
batteries....(depending on length, I recommend 6ga - 2ga)
Although many self installers do not do so, ABYC rules state that you should have a fuse/breaker within 7" of the
battery end of this wire....
(although running your 6ga - 2ga wire, to "battery side" of the main battery switch is acceptable in
some cases...assuming the run from the main battery switch to the batteries is very short, < a couple feet, and is 00ga or larger...the approach I detail above is always what I recommend....and it doesn't cost you much, nor take much time...)
Some folks question the reason for this recommendation....and while I don't have the time for all the regular minutia...here's the gist of "why"...
-- Giving your radio "clean" power is always a good idea, and will always make it work better!!!
-- Having the radio draw directly from the batteries, NOT thru a dist panel / breaker panel, will prevent/reduce flashing and dimming of lights and voltage sags on other systems on-board...
--- Having the radio draw directly from the batteries, NOT thru a dist panel / breaker panel, will also prevent/reduce RF energy that may flow along the power wires, or that is being picked up by the power wires, from causing
interference into other systems on-board...while you are transmitting...
-- Having the radio draw directly from the batteries, NOT thru a dist panel / breaker panel, will also prevent/reduce RFI (interference) FROM other systems on-board, causing problems with your receiving of signals...
-- Having the radio draw directly from the batteries, NOT thru a dist panel / breaker panel, will improve the voltage available to the radio (less voltage drop), and allow the radio to preform to its optimal capabilities...
-- Having the radio draw directly from the batteries, NOT thru a dist panel / breaker panel, will actually allow the radio to draw less power from your batteries (taking less A/H's from your batteries), as there will be less voltage drop and hence less
current drawn....which means you'll be using less power, and means the radio will not be using as much power as it would otherwise...
-- The large house battery bank acts as a large "filter", reducing radiated RFI....
-- Using a larger sized wire is very important here as well....as the radios are designed to run on 13.6 - 13.8vdc (what everyone on land calls a "12 volt radio")....and on-board most will not have voltages like that available unless they are
charging (solar,
wind,
water, genset,
alternator, etc..)...so keeping the voltage that is supplied to the back of the radio WHEN TRANSMITTING (not on a panel meter!) as high as possible is VERY important!!!
[Note that MANY / MOST modern ham transceivers will NOT work correctly when voltages (at the radio) are below 12.5 volts...and MANY / MOST will have severe distortion and other issues when the voltage dips to near 12.0 volts....and MOST (all?) of them will quit transmitting, or cut-out intermittently when the voltage dips to near 11.5 volts (when transmitting)!!!
If you're batteries are at 12.2 - 12.3 volts (which is very plausible), even with a BIG guage wire, you're probably going to have problems, and if you have even as little as a 3% - 5% voltage drop, you're radio may become useless on transmit....
This is just one of the many reasons that a REAL
marine transceiver (such as an M-802, M-710, etc.) is such an improvement....as they are not only "spec'd" to handle a wider range of input voltages, but they MUST meet their rated specs and meet (or exceed) the FCC / ITU specs for
commercial marine
service when operated AT their MINIMUM, MAXIMUM, and NOMINAL voltages....
Which in the case of the M-802, is from 11.5vdc to 15.6vdc (nominally 13.6vdc +/- 15%)....
That means it will still work to it max rated specs AND meet the FCC Part 80 spec (for
commercial marine service), with a voltage (AT THE RADIO) of as low as 11.5 volts!!!
Some may then question why spend the $$ on bigger wire....my answer is, read all of the above!!!]
2) Do NOT worry extensively about your RF Ground /
Antenna Ground /
Counterpoise.....
Despite the arguments on-line, that seem to go on-and-on, it REALLY isn't that difficult of an issue!!!
(You do NOT need to spend days running 100 sq ft of copper mesh/foil thru your bilges!!! That is a waste of your time!!!)
Instead, find a good location for your
remote antenna tuner (such as the AT-140, SGC, etc.), where you can get at it, and where you can run the wires to it....
Make sure it is within a few feet (< 3' - 5', but closer is better) of your antenna base (backstay, whip, alternative backstay, rope-tenna, etc.) and within a few feet (<5' - 8'....but closer is better) of an underwater metal
thru hull or grounding plate (bronze thru-hull, or Dynaplate)....
Use GTO-15 antenna wire, to run from the tuner to your stay or whip, etc...and understand that this IS part of your antenna, and a VERY important part!!
Keeping this run of wire as short and as much in the clear, away from EVERYTHING else on-board is VERY important....do NOT place it near, nor run it along other wires, etc.. NEVER....
Use wide copper strapping NOT thin copper foil....I recommend at least 0.012" thick copper strapping, 3" wide....(I use 0.022" thick 6" wide, but I'm a fanatic!!)...and run this as short of a run as possible from the
remote tuner's "grd" lug to your nearest underwater
bronze thru-hul or grounding plate....
{You CAN do more for RF grounding /
counterpoise, such as pushpits, pullpits, alum toerails, tuned-radials, additional grounding straps to a
keel bolt, etc....but you run into the laws of diminishing returns....so do the above FIRST, and then see what else you may desire to do....unless you're doing a complete vessel re-fit, where you have her gutted anyway, then add in as much as you can...}
For the coaxial cable and power/control wires from the radio to the remote tuner, use a coaxial line isolator on the coax line (at the tuner end) and clip-on ferrites on the tuner power/control cable....
Line isolators and ferrites are available from DX Engineering and Radioworks...I've used both, and both work fine....(although, I prefer DX Eng...and they are really nice guys to do business with!!)
http://www.dxengineering.com/parts/dxe-fcc050-h05-a
http://www.dxengineering.com/search/...-ferrite-beads
T-4
Line Isolator System
Do NOT run any "ground strap" between the M-802 transceiver (radio) and the AT-140 tuner....NOR, from the M-802 transceiver to your RF Ground system, thru-hill, grounding plate, etc...NO matter what the manual says, do not do it...
This can cause ground loops and can cause RFI problems on-board...(read some of my other postings, the Sailmail primer, radioworks site, etc. for more details. if desired...)
3) Understand that much of the consumer electronics that surround us these days, even on-board our boats (and a surprising amount of the basic
electrical devices on-board boats), can generate Radio Frequency
Interference (RFI), and ridding your
boat of devices that do this, and/or shielding/filtering this interference, and/or simply removing the
electrical power from these devices while using the HF Radio, will make a substantial difference in your ease and success in using HF Radioon-board....
Here again video #9 (and #4, and #5, as well) on this thread will be of help...
Getting rid of on-board RFI, or at least being aware of exactly what is causing it and being able to switch off these systems/devices when needed, will go a long way to your successful use of an HF Radio...and using clip-on ferrites on all of your interfering systems' power and control wires, AND on all of your on-board electronics signal and power wires, etc. might seem like overkill, but it does work!!
The most common causes of RFI on-board are:
-- inverters of all types / sizes...
-- battery chargers, of all types/sizes (not just your big house bank
charger, but also small
cell phone chargers and battery drill chargers, etc..)
-- microprocessor controlled circuits / timers...
-- inferior LED
lighting voltage regulators...
-- refrigeration/freezer compressors....(you'll mostly just learn to live with them
-- small,
cheap electric motors, such as 12 volt fans...
-- digital panel meters, remote sensing devices, etc...
The list of potential RFI sources goes on-and-on....the easiest way to find them all is first get away from shore (1/2 mile or more is usually fine) and way from other boats to....(so that you will not mistake locally generated RFI, from shore or other boats, as coming from your boat!!)
And, then simply power down the whole boat, removing power from everything, switch off all breakers and battery switches, and remove all
fuses, etc...
Then turn on you HF Radio and tune thru all your channels (or at least your most often used dozen or two), and listen and note any noises (including the signal strengths)....and then switch on the battery switch(es) and listen again...and then switch on one breaker at a time, and then turn on that one item/system (again, just ONE-AT-A-TIME), and listen again to each channel, noting the noises and signal strengths....
It will become quite apparent, quite quickly, when you find an interfering system/device....and then you'll need to filter/reduce the interference (ferrites, better
wiring, move
wiring, etc...) and/or accept and live with this interference...
4) Finally, the last of my
installation tips, might seem less like an installation tip and more of an operating tip....and I suppose it really is...but it is VERY important, nonetheless!!
You should spend the time (a few hours at most) to LEARN about HF Radio Communications, HF Radiowave Propagation, and How-to-Use your radio!!!
This IS so very important, I cannot stress it enough!!!
ALL OF THE ABOVE "TIPS" ARE USELESS if you, the radio's user, is ignorant on how to properly use the radio!!!
Many sailors will spend hours/days/weeks/months
learning sailing,
anchoring,
navigation,
diesel mechanics, watermakers,
scuba diving, etc etc..some will spend 1000's of $$$$ on classes/courses, some will desire to attain certifications and/or licenses (even a ham radio license), but never spend any more than 15 minutes reading a radio manual and never truly invest the time to LEARN how to use an HF Radio properly...
The information is out there (some of it right here in this thread and some in these videos, but there is a LOT more out there as well!), all the sailor needs to do is ask and be willing to learn!!!
Bottom line here is a VERY important (and indisputable) fact:
An experienced and well trained radio operator, can make excellent use of, and have great success with, even a poor to mediocre radio set-up/installation!!!
But, a inexperienced and poorly trained radio operator will have very poor results and NOT have much success at all (probably even none!), even with a perfect radio set-up/installation!!!
These are well-proven, long-established, FACTS....that somehow new/novice HF Radio users seem to discount/dismiss....
And, heck even some old-times seem to refuse to understand that learning is a life-long process!!!
If I had a dollar for every time I heard even long-time hams make obvious false statements, or seasoned hams propagating myths, etc. I'd be a VERY wealthy guy!!!
So, PLEASE accept the above facts about operator experience / training as actual facts....and spend some time learning about HF radio and radiowave propagation, and you'll be very happy that you did!!!
5) I do hope the above helps....and FYI, the above installation tips (#1 - #3) are NOT my sole original ideas!!!
These have been the accepted "good engineering practice" for decades and have been part of Sailmail's installation guidelines for > 10 years now...
Even if you are not planning on installing a
PACTOR modem (I don't have one either), it makes good sense to follow Sailmail's installation guidelines!!!
a) Read the Sailmail Primer, and follow their guidelines...
SailMail Primer
SailMail
b) Use my installation tips (above)...
c) Read over the SSCA Discussion Boards, for a MUCH greater wealth of info on HF Radio and installation tips, problems, advice, etc...
http://www.ssca.org/forum/viewforum.php?f=5
d) Use my videos and postings to learn the basics of hot-to-use your radio....
Do all of these things and you should be very successful!!
Fair winds and good luck!!
John, KA4WJA
s/v Annie Laurie, WDB6927
MMSI# 366933110
http://www.qrz.com/db/KA4WJA
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