OK, I am HF certified... now what?

[carstenb]

Originally Posted by Rustic Charm

That's a good suggestion I'll do that. The radio part of it works fine, but I'll call someone who I've arranged it with.

Can I ask, third time, are you using VHF or SSB? Or both?

And does the DSC operate across both radios?

Rustic

Maybe I didn't explain it properly. A high frequency radio wave is sent at an angle upwards where it will bounce off the atmosphere and come back down. The ground length of this "bounce" (meaning where it comes back down) is something like 1000/1500nm, meaning if you are less than 1000nm from the sender - you simply will not hear their radio call because you are inside the cone formed by the radio wave bouncing off the atmosphere.


Since VHF means Very High Frequency and HF means High Frequency - a DSC signal sent on one radio(f.eks VHF) will not be heard on the other type of radio since the VHF DSC is being sent on a wavelength the HF radio does not receive.

Hope that helped

carsten

[Rustic Charm]

Originally Posted by carstenb

Each radio has its own DSC - so when I call a ship to agree a starboard to starboard passing, agree intentions or similar - I can usually see them or at least see them on my AIS, here I use my VHF radio.

I've had no reason to try to call a ship 1000nm away, but I have called other sailors who have an SSB and spoken with them (in the MED). Again I simply dial (push buttons) their MMSI number and assuming they are in the mood to talk - they'll answer.

AS I noted earlier - trying to call someone on your SSB who is only 20-25nm away is a non-starter. you'd need to to be sending with enormous power, maybe 500-600 watts or the receiver would need a huge antenna.

I tested my SSB with a local Ham operator, 20nm away. He could hear me when I sent with 150 watts (he has an enormous antenna array) and I could hear him when he powered up to 700 watts.

Thanks. I don't have an SSB yet. I'll get my VHF set tested with someone I know at the club. I've tried perhaps sic or seven times and so far not got anyone to respond. I had wondered whether the ships I've tried to call, which I've identified on AIS simply arnt DSC equipped yet? Which means they would not be hearing the call.

[carstenb]

Originally Posted by Rustic Charm

Thanks. I don't have an SSB yet. I'll get my VHF set tested with someone I know at the club. I've tried perhaps sic or seven times and so far not got anyone to respond. I had wondered whether the ships I've tried to call, which I've identified on AIS simply arnt DSC equipped yet? Which means they would not be hearing the call.

I doubt very much that any AIS ship is not VHF DSC equipped. I would also doubt that any commercial ship is not DSC equipped. This type of equipment is requried.

I'd test my VHF if I were you - I suspect the problem is at your end.

[SimonV]

The following list is next to my 802 for choosing the band of frequencies to find your first bounce:

2 MHz 200-400 miles
4 MHz 400-600 miles
6 MHz 600-1,200 miles
8 MHz 800-1,600 miles
12 MHz 1,200-2,400 miles
16 MHz 1,600-3,200 miles
22 MHz 2,200-4,000 miles plus
26 MHz ???????


2 MHz low power seems fine for line of sight out to 200 miles plus.

[GILow]

Originally Posted by SimonV

The following list is next to my 802 for choosing the band of frequencies to find your first bounce:

2 MHz 200-400 miles
4 MHz 400-600 miles
6 MHz 600-1,200 miles
8 MHz 800-1,600 miles
12 MHz 1,200-2,400 miles
16 MHz 1,600-3,200 miles
22 MHz 2,200-4,000 miles plus
26 MHz ???????


2 MHz low power seems fine for line of sight out to 200 miles plus.

So, at the risk of exposing how little I understand (hence my desire to get learning now) what do you do when the "net" you are trying to contact is listening on a frequency incompatible with those transmission distances?

So if "Cruiser's Bargain Boat Bits" HAM net was operating around the 6 MHz range, but I am 1500 miles away, I read this as my bounced signal will overshoot them and they won't hear me (or me them.)

Very confused

Matt

[SimonV]

Its all a guide. I spend most of my time in the 4 and 6 MHz during the day. If you can hear the net they should hear you.

[GILow]

Originally Posted by SimonV

Its all a guide. I spend most of my time in the 4 and 6 MHz during the day. If you can hear the net they should hear you.

So, from the word "should" I can infer that there will be times that the net you wish to contact will be sitting at a distance that you can't communicate with? Either too far, or, oddly enough, too close?

[Snowpetrel]

These hap charts are interesting http://www.ips.gov.au/HF_Systems/6/6/1 propagation is pretty weird! Night and day is like.. well night and day.

In theory aus and NZ are still monitoring 4,6 and 8 mhz (nz 12,&16) but I wouldn't stake my life on being able to raise them, especially during daylight hours.

On a square rigger I was mate on we occasionally had trouble sending the met obs from the Pacific islands back to nz with a big 250w set. Usually got through at night, if we had missed a daytime Obs.

Saying all this I love the romance of HF. The static with a slightly distorted voice link to a faraway place is always a thrill. For this reason alone I will continue to carry and use a HF.

Sent from my HTC_0PCV2 using Cruisers Sailing Forum mobile app

[carstenb]

Originally Posted by GILow

So, from the word "should" I can infer that there will be times that the net you wish to contact will be sitting at a distance that you can't communicate with? Either too far, or, oddly enough, too close?

LOL Welcome to the wonderful world of radio signals propagation. You're right sometimes you can be too close or too far.

Occasionally a "skip" will occur and you can find yourself talking on your VHF to someone a few hundred NM away. Once when I lived inthe US and had a CB set - I spoke with a guy in california and I was in virginia. The skip only lasted a couple of minutes though then he faded out.

[GILow]

I think this all just confirms my concerns. I need to get practising with this stuff.


And Snowpetrel captured what I perceive as the joy of the whole thing with the remark about the "Romance of HF". Back in my younger days we used to muck around with AM CB radio and we had so much fun. My favourite game was one called "Cat and Mouse" where someone would hide somewhere in town (a town with about 50,000 people) and transmit from their car and the rest of use had to find them. One year someone clever parked themselves near the concrete channel that diverted the river around the city centre and had us all chasing their signal 10 miles away at the other end of the river. Now that was some very strange skip.

[ka4wja]

Matt,
I understand your query / situation...

Originally Posted by GILow

So I have finally got around to doing my HF marine radio certification.
...I am now unsure what to do next.
....At the moment I do not have a HF radio on the boat. We need to buy a radio, clearly, but what to buy and when is still uncertain.
....But doing the HF course made me feel that there is a bit of a black-art, or at least some skill required to operate marine HF and now I am wondering if I should bring the HF forward a bit. And if I do bring it forward, how do I learn to use it. I mean, I would kind of feel silly trying to join a cruisers net from the pen at the yacht club. Or is that OK? I feel I need to USE the radio to know how to use it.

Can anyone enlighten me?

Matt

And, yes, I CAN enlighten you!!

Originally Posted by GILow

I am most concerned with getting some meaningful use of it in the interim once I have bought one. I am wondering how I should go about getting practiced at using HF. But maybe the answer is to go down the HAM path instead, and get some time that way? It appears that the skills are transferrable?
Matt

1) First, it isn't rocket science, nor is there much of "black art" involved at all!!!
(while yes, there is no substitute for experience and well-explained knowledge....no matter what anyone tells you, there is VERY little "black art" at all....it is all very explainable and as long as you use the proper equipment and follow the basic rules, it is actually VERY reliable!!)

2) Secondly, yes, experience / getting used to the radio, and especially HF radiowave propagation and HF radio operating techniques, are important to getting both optimal performance out of your system, but also in making things easy and comfortable....

3) I have attempted to ease the learning curve a bit, by making a significant number of videos and assembling some into specific Youtube Playlists that allow you to follow along in a logical manner, from the novice/beginner to the more intermediate radio user, covering the basics of:
--- radiowave propagation
--- radio operation
--- HF marine (SSB)
--- specific functions / features
--- noise / interference
--- distress signaling
--- weather information
--- DSC
--- ham radio
etc. etc. etc. etc...

If you have decent internet connection (can watch standard definition Youtube videos), and have an hour or so....watch these videos and you WILL learn a LOT...
(and once you have a radio in front of you, you'll already know quite a bit...and then you can re-watch them, with the radio in front of you, and you'll be proficient enough for most of the basic marine SSB operations!!)

Please have a look...
And, take note that these videos are shot LIVE, on-board my boat, sitting at the dock, using all real-world signals and in real-life, so you can see (and HEAR) exactly what to do, and what it sounds like!!!
LIVE, in the REAL-WORLD....no laboratory, no simulations, no examples, no boring instructors, etc....and no fancy video production nor editing either, sorry about that!



These videos show the REAL thing...LIVE as it happens....

Marine HF Comms...
https://www.youtube.com/playlist?lis...ZDo_Jk3NB_Bt1y

Marine HF-DSC comms..
https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX

Icom M-802...
https://www.youtube.com/playlist?lis...rC-8QKVyMb4tVr


Offshore weather...
https://www.youtube.com/playlist?lis...zdjTJjHlChruyY



And, here are some threads with some real-world practical info for you...
Tips for using an HF-SSB Radio (mostly for newcomers)

HF Radio Freqs, summertime Atlantic crossing, offshore Net..

Offshore / Hi-Seas Weather data / forecasts


Also, here is the extensive thread (actually a "sticky") where you'll find almost all the references you'll ever need about HF Marine (SSB) radio, how-to use it, how-to install it, how-to troubleshoot any issues, etc...
http://www.cruisersforum.com/forums/...tc-133496.html


And, if you wish to learn more and move into the amateur radio field, the ARRL here in the US has some great on-line resources (and I suspect you have similar resources downunder as well??)
www.arrl.org







4) FYI, yes, in addition to being the only real affordable HF-DSC-SSB Radio telephone on the market, the Icom M-802 also works very well on the ham radio bands, and makes an excellent ham rig!!!
(I even have a video specifically showing this...)







There is a LOT more I could write, but this answers your specific questions directly and should get you going in the right direction...


I hope this helps...

Fair winds...

John

P.S. I have > 40 years of HF communications experience, both marine and ham, at sea and on-shore....so, sometimes I tend to assume others will "get it" quickly.....but, when setting out to explain HF-DSC, I used my 64 yr old non-tech sister and my 94 yr old non-tech Mother (both of whom are sailors), to critique my videos and give me ideas about editing....but, my earlier videos (the M-802 specific videos) I sort-of assume that everyone had the radio in front of them....so, if you find some things not explained well enough, please let me know, and I'll try to explain it here!!

[ka4wja]

Well, I don't wish to pick on anyone specifically, and I think carstenb is trying to explain things as best he can....BUT...
But, this info is very flawed...sorry...


In addition to watching the videos I linked to above and reading the threads I referenced above, perhaps a bit more specific info here will help???


1) First off, for explanation and LIVE, real-world demonstration of HF radiowave propagation, please have a look this video...(video #1 in the Maritime HF Communications playlist)

https://www.youtube.com/watch?v=T-1L...B_Bt1y&index=1

2) Secondly, please read over this thread, where the various ranges of different HF frequencies/bands is explained in laypersons terms...
HF Radio Freqs, summertime Atlantic crossing, offshore Net..


3) Third...
The most often misunderstood part of HF radiowave propagation and communications is, how the radio waves travel and how they are reflected!!
{please understand that to write a treatise here about radiowave propagation would take WAY more time than I have available....so please watch the videos and read the other threads, 'cause I just cannot continue to re-type everything, every few months!! }

Fact 1: "local" / "close-in" HF comms (from 10 miles out to 300-400 miles is almost always (99.999%) via Near Vertical Incidence Skywave (NVIS) on the frequencies between 2mhz and 9mhz.....
And, this is VERY easy and very reliable....
And, most will find daytime comms beyond 400 - 500 miles on these lower frequency bands (2mhz thru 9mhz) to be non-existant....(although, at night, the range can be 1000's of miles)

Fact 2: HF radiowave have VERY little groundwave component, and the higher in frequency the shorter and weaker the "groundwave" is....(ex: on freqs above 14mhz, it can be as short as 5 - 10 miles, and even then it can be weak...)

Fact 3: Knowing what frequency band to use, based on the distance to communicate and the time-of-day (and even to a lesser extent, time-of-year), is the single most important thing that new HF radio users must learn....(and understand that there is NO "black art" to this....it is very teachable and repeatable)



4) Some helpful hints / opinion...
a) The way I start to explain it to laypersons is this:
"the higher the sun, the higher the freq....the lower the sun, the lower the freq...and the shorter the distance, the lower the freq...the longer the distance, higher the freq..."
(the sun is of course "lower" at night, since it is below your horizon...)
Once you learn this simple set of rules, then you're ready for specifics...

b) Specifically for HF communications on-board (using our antennas and radios):
Daytime:
--- Ranges from 0 to 400/500 miles = 7mhz - 8mhz
--- Ranges from 250/300 miles to 3000/4000 miles = 12mhz - 14mhz
--- Ranges from 500 miles to 6000 miles+ = 16mhz - 25/26mhz....
{you may see that I didn't list 2mhz, 4mhz, or 6mhz for daytime use???
and you may be wondering why??
especially because many "local" cruising nets use these freqs??
The reason is three-fold...
a) there is typically much greater noise on the lower bands...
b) typical cruising boat antenna systems are less efficient on these lower bands..
c) typically 7mhz to 8mhz is superior in all aspects....(except for the very close comms, 10 - 25/50 miles, when close to sunset / just after sunrise....where the lower bands might be better...)

So, if you wish to see the real-world daytime ranges for these bands, here 'ya go...
--- Ranges from 0 to 100 miles = 2mhz (NOISY!)
--- Ranges from 0 to 200 miles = 3.6mhz - 4.5mhz (still noisy!)
--- Ranges from 0 to 300 miles = 6mhz (still noisy) }

Nighttime:
--- Ranges from 0 to 300-500 miles = 2mhz (but still noisy!)
--- Ranges from 0/50 miles to 3000/4000 miles = 3.6 - 4.5mhz (but typically noisy, especially in tropics!!)
--- Ranges from 100 miles to 4000/5000+ miles = 6mhz, 7mhz, and 8mhz...
---- Ranges from 300 to 4000/5000+ miles (early evenings) = 12mhz, 14mhz, and sometimes 16mhz to 21mhz...but typically not usable much beyond a few hours past sunset...



5) Some specifics in red....

Originally Posted by carstenb

AS I noted earlier - trying to call someone on your SSB who is only 20-25nm away is a non-starter.
In reality, as long as you choose the correct freq, this is actually a very easy form of HF comms, and is very reliable!!

you'd need to to be sending with enormous power, maybe 500-600 watts or the receiver would need a huge antenna.
In truth, high power and large antennas are NOT needed at all!!! (again, as long as you choose the correct freq, this is actually a very easy form of HF comms, and is very reliable!)

I tested my SSB with a local Ham operator, 20nm away. He could hear me when I sent with 150 watts (he has an enormous antenna array) and I could hear him when he powered up to 700 watts.
In addition to freq choice, there are other reasons for this....noise, RFI, use of vertical antenna on-board and horiz antenna on shore, etc...

Originally Posted by carstenb

Maybe I didn't explain it properly. A high frequency radio wave is sent at an angle upwards where it will bounce off the atmosphere and come back down. The ground length of this "bounce" (meaning where it comes back down) is something like 1000/1500nm, meaning if you are less than 1000nm from the sender - you simply will not hear their radio call because you are inside the cone formed by the radio wave bouncing off the atmosphere.

This is only true on the very high end of the HF radio spectrum, but NOT the case for all the HF bands, and certainly not the case fro daytime comms on the lower bands (below 9mhz)!!
See details above, in the videos, and in the other threads referenced...

Originally Posted by SimonV

The following list is next to my 802 for choosing the band of frequencies to find your first bounce [not really about where the signal will bounce, nor are these precise about the typical/normal ranges (see above), but Simon is close...]:

2 MHz 200-400 miles
4 MHz 400-600 miles
6 MHz 600-1,200 miles
8 MHz 800-1,600 miles
12 MHz 1,200-2,400 miles
16 MHz 1,600-3,200 miles
22 MHz 2,200-4,000 miles plus
26 MHz ???????


2 MHz low power seems fine for line of sight out to 200 miles plus.

Again, as long as you watch the videos and read the other threads referenced, I do think this will help....

fair winds..

John

[GILow]

Originally Posted by ka4wja

... And, yes, I CAN enlighten you!!

Hello John, thank you for posting a reply. I will read what you have written here in a moment, but first I would like you to know I am already half way through your series of videos on youtube, which I found when I first started looking into HF on Cruisers Forum, and they really are excellent.

I'll come back with a question about the 802 in a moment, once I have confirmed that you have not already addressed my concerns.

Matt

[GILow]

OK, I've got many more happy hours of youtube watching ahead of me I see.

John, with regard to the 802, I am aware some low level rumblings about the reliability or otherwise of this particular radio. I have read your posts on the frustration of getting people to be aware of the clipping issue and the simple fix thereof (send it to the makers, they will fix it, or if you are REALLY keen and well setup solder in the 470K resistor yourself) and I also read of your caution about shoddy installations allowing RF intrusion.

So, generally speaking, are you happy with it once it has been installed correctly, particularly on an older medium large fibreglass boat. The boat in question is very "dry" as boats go, but I note that the 801 was much more "marine-proof" in the design.

If you were not worried about cost, and were thinking simply of robust and flexible radio, particularly the ability to use the HAM bands, would you recommend the 802 or would you be going another path?

(I am starting to understand why the boat had a Kenwood TS-430 when I bought it.)

Finally, I would appreciate your thoughts on manual vs auto tuners, when in this case you have a reasonably technical person on board who is likely to be able to drive either setup properly once trained in their correct use.

Matt

[El Pinguino]

Originally Posted by GILow

OK, I've got many more happy hours of youtube watching ahead of me I see.

John, with regard to the 802, I am aware some low level rumblings about the reliability or otherwise of this particular radio. I have read your posts on the frustration of getting people to be aware of the clipping issue and the simple fix thereof (send it to the makers, they will fix it, or if you are REALLY keen and well setup solder in the 470K resistor yourself) and I also read of your caution about shoddy installations allowing RF intrusion.

So, generally speaking, are you happy with it once it has been installed correctly, particularly on an older medium large fibreglass boat. The boat in question is very "dry" as boats go, but I note that the 801 was much more "marine-proof" in the design.

[COLOR="rgb(46, 139, 87)"] If you were not worried about cost, and were thinking simply of robust and flexible radio, particularly the ability to use the HAM bands, would you recommend the 802 or would you be going another path[/COLOR]?

(I am starting to understand why the boat had a Kenwood TS-430 when I bought it.)

Finally, I would appreciate your thoughts on manual vs auto tuners, when in this case you have a reasonably technical person on board who is likely to be able to drive either setup properly once trained in their correct use.

Matt

I can't comment on the clipping issue but assumed that had been resolved by Icom on the newer radio.
I won't comment on DSC either except to say I was scared for life by experiences with it when it first appeared on commercial ships....

Moving right along I would say the 802 would be the way to go... not a whole lot dearer than a new 710 and only a part of the whole system.... lookee here and scroll down ... Marine Radio Packages - Marine HF SSB Radios - Icom M802 HF Marine Radio WITH DSC IC-M802 (DSC Version) 2 Year Warranty - radios.net.au shop

Only way to go would be an Icom AT-140 tuner .... its automatic... manual tuners make my brain hurt....

Simple to set up... power to radio.... coax and control cable to tuner... connect your ground and your ant to the tuner and away you go... easy when you say it quick..

What are you going to use it for?
I receive fax and voice weather on the marine bands but I can do that with a $100 portable...
I use it on occasion on cruising nets... the Isabella Net (? I think thats what it was called ) up in Polynesia and the Patagonian Net are both on Marine bands.
Its primary use is HF email /Sailmail and I get my money's worth from the above.

In the Tasman / E coast Oz area there are a couple of cruising nets on the ham bands, Tony's in NZ and the Comedy Net on the East coast.
Ham radio is very much whatever you want it to be........