a silly question but = SSB

[john61ct]

With commercial outfits taking over, they'll be monetizing soon, like the old 900 calls but $20 a minute

[stormalong]

Originally Posted by continuouswave

Putting aside the various problems of signal level, path loss, attenuation or reflection in ionosphere layers, and crew availability, the principal problem of communication with the ISS is going to be the chance the ISS is in view from your location with an elevation angle 15-degrees or higher

The ISS orbit is 250-miles high. At that height the amount of the total Earth surface from which the ISS appears in the sky at an elevation angle of 15-degrees or higher is only 1.4-percent.

The chance that at a particular moment the ISS will be in view with at least 15-degrees elevation angle from a random point on Earth is correspondingly low.

To further diminish the probabilities, the nature of the ISS orbit must be considered and your location must be considered. The ISS orbit is only inclined 51.6-degrees, which means its ground track on Earth is never higher in latitude than 51.6-degrees North or South. If you are in latitude higher than 51.6 North or South, the chances of the ISS being in view is just about zero.

For some background on nadir angles from satellites, and percentage of earth surface as a function of orbit height, see

Nadir Angle and Elevation Angle - CONTINUOUSWAVE

It is even more complicated, You need a directional antenna and an azimuth and elevation to point it. Also need the astronauts to be operating when you call.

A little google searching should get you to a site that tells you when the ISS is in view and a spotting site that will tell you when they are operating. A little difficult to do in open ocean.

I think most of their ham activity is related to school contacts set up well in advance.

[S/V Illusion]

Originally Posted by Scorpius

I seem to remember that an Extra Class license (I used to have one: AB6KL) was required to speak with the shuttle. Is it the same for the ISS?

No. Unless they (the ISS) is operating on a frequency only authorized for Extras. But they do not.

[ohgary]

While the shuttle no longer flys, the space station does have ham gear. Your going to need VHF and or UHF ham gear to talk with them, know the schedule they are operating and when they will be seeking general contacts vs pre-arranged school contacts.

I did talk to the shuttle many years ago, as well as the mir space station and the international space station. Fun but usually only last a few minutes with the fast speed they are going.

[tkeithlu]

"A marine SSB can operate legally on the amateur radio bands.

Still not quite right. The radio can do it, but the guy squeezing the PTT button needs a General Class ham license.

[stormalong]

Originally Posted by tkeithlu

"A marine SSB can operate legally on the amateur radio bands.

Still not quite right. The radio can do it, but the guy squeezing the PTT button needs a General Class ham license.

Still not exactly right. Technician class and even Novice class (which there are still a few around) have voice privileges on the 10 meter band and CW privileges on the 80, 40, 15 and 10 meter bands.

[ohgary]

Originally Posted by tkeithlu

"A marine SSB can operate legally on the amateur radio bands.

Still not quite right. The radio can do it, but the guy squeezing the PTT button needs a General Class ham license.

and can a marine radio converted to the ham bands be convert back to marine and still meet type acceptance?

[stormalong]

Originally Posted by ohgary

and can a marine radio converted to the ham bands be convert back to marine and still meet type acceptance?

They are not converted. An option is set within the radio to allow transmission on the ham bands. This does not affect marine SSB operation. There are only a few Marine SSB radios that can do this. These radios are software controlled and the software sets the operating frequency limitations.

[tkeithlu]

ohgary, it's clipping one diode to remove the radio's restriction on transmitting on those bands. The radio stays the same; before if you pressed the PTT, you'd get an "Error" or just nothing, after, it transmits. From all of us who worked our butts off getting the licenses that require this understanding, please don't go wandering about the ham frequencies pressing buttons.

In this terrestrial area, the problem is hunters buying 2 meter (VHF) radios, opening them, and transmitting on any frequency that comes to mind, including the ambulance to hospital one and our county fire department net.

[S/V Illusion]

Originally Posted by tkeithlu

"A marine SSB can operate legally on the amateur radio bands.

Still not quite right. The radio can do it, but the guy squeezing the PTT button needs a General Class ham license.

If you are going for precision -
“At least” a General class license.

[continuouswave]

Originally Posted by stormalong

It is even more complicated, You need a directional antenna and an azimuth and elevation to point it. Also need the astronauts to be operating when you call.

Re-read my comments in which I mention putting aside those problems in order to consider the location of the ISS relative to your position on Earth.

A directional antenna is not absolutely necessary, as I demonstrated in the path loss analysis.

In any situation in which many amateur radio stations might be calling one other station--known as a pileup--the loudest signal is the one to get through. If you are the weakest signal, you might never get through the pileup.

Receiving weak signals in space is generally not a problem because the local noise level is often very low, at least compared to the noise level on Earth. Weak signal reception on Earth is generally limited by local noise sources, usually noisy power lines, spurious signals from consumer equipment, noisy electrical devices in the home or in adjacent homes, and so on. Weak signal reception in space is generally limited by the local radio noise on the spacecraft, which is usually very well designed to be very low. Of course, pointing an antenna at Earth also brings in a lot of Earth-generated noise.

As someone suggested earlier, a 5-Watt handheld might be able to be heard at 250-miles on 145-MHz if conditions were favorable, that is, no other stations competing, no local noise at the receiving end, and perhaps some antenna gain at the receiving station.

[continuouswave]

Remarking about my comments about percentage of earth surface in view to a satellite at 250-Miles high:

Originally Posted by stormalong

It is even more complicated...

Actually, it is more complicated, but not for any of the reasons you mentioned, which I excluded from my remarks.

Because the orbit of the ISS is inclined at 51.6 degrees, there is a large part of the Earth over which it will never appear at an elevation angle greater than 15-degrees. Let's assume anyone higher than 55-degrees is out of luck. The area in which the ISS will actually ever be in view is then already less than the total area of the Earth. We'd have to calculate just what that area would be, then figure out what percentage of that area is in view at 250-miles up. So the percentage of the POSSIBLE areas of Earth where you could see the satellite and the area in view to the satellite would be be calculated to be higher than the 1.4-percent I mentioned earlier.

[CaptainJohn49]

Boy you guys are smart. Sailors must have a lot of time to play with their ham sets. Can’t understand sailing much less ham radio.

CaptainJohn49
KG7YBI

[belizesailor]

Originally Posted by CaptainJohn49

Boy you guys are smart. Sailors must have a lot of time to play with their ham sets. Can’t understand sailing much less ham radio.

CaptainJohn49
KG7YBI

But yet you sign off w your call sign...a bit of sarcasm?

A ham hamming it up? [emoji6]

[CaptainJohn49]

Kinda, although I knew you could contact the ISS I don’t personally know anyone who has done it. These guys and girls on these forums know all kinds of things. That’s one reason I love to follow them. Keeps the mind active.

CaptainJohn49