166
Shortwave Pirate Radio In North America And Around The World, And Other Signals That Go Bump In The Night
We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations.
Always consult with the appropriate authorities if you have questions concerning what is permissable in your locale.
OK, that sounds like FLTSATCOM 8 is in a slightly inclined orbit, doing the figure 8 stuff.
Is it possible FLTSATCOM 7 is being moved? To shift an orbital slot, the satellite is moved slightly closer to or farther from earth. That causes it to move East or West. When it gets to its new orbital slot, the satellite is parked back into the geo orbit. This uses fuel so it is not done often.
FLTSATCOM 7 is old. I suspect that it is just in an inclined orbit.
If you look here:
https://www.n2yo.com/satellite/?s=17181
You will see that it has an inclination of 14.5 degrees, which is a lot for a geo.
UFO8, seen here:
https://www.n2yo.com/satellite/?s=25258
has an inclination of 8.6 degrees. There will be motion about the suborbital point, but not as much as for FLTSATCOM 7.
Compare the motion along the suborbital point for each of them.
If you compare this to, say, DIRECTV 15, as seen here:
https://www.n2yo.com/satellite/?s=40663
you will see an orbital inclination of 0 degrees and a sub orbital point that doesn't move. This satellite has Ka band transponders and a user base that does not have tracking antennas. It must stay in position, otherwise it will move outside the mainlobe of the user antennas. More fuel will be expended to keep that satellite in position.
Geostationary orbits are a form of equatorial orbit.
FLTSATCOM 7 is in a geo orbit.
https://space.skyrocket.de/doc_sdat/fltsatcom-2.htm
Maintaining a geo satellite with a near zero orbital inclination uses up station keeping fuel. One tradeoff the designer has is to allow small amounts of inclination (for example +/- 5 degrees) to develop. Doing this means you don’t have to perform station keeping maneuvers quite so often, saving fuel and extending the lifetime of the satellite.
To the observer on earth, this results in the satellite apparently “wandering” slightly in the sky, drawing a figure 8 pattern on the suborbital point on the earth. Maintaining a bore site on the satellite would require a simple antenna tracking mechanism, but the beamwidth of most directional UHF antennas is broad enough that this isn’t necessary. On Ka band it would be.
FLTSATCOM 7 and 8 are beyond their planned lifetime. I wouldn’t be surprised to if a decision had been made to leave them in place as long as they were working, but to allow them to develop some orbital inclination.
When a geo satellite is “retired” it is placed in a graveyard orbit. This requires less fuel than deorbiting the satellite. The satellite is pushed a few 100 km farther out than the geo orbit and left there. This frees up that geo slot for another satellite.
Also, you are talking about FLTSATCOM 8, not UFO8, right?
I have one of those. It works, but the one I have from www.rescueelectronics.com works a little better.
I would recommend caution with the bypass switch that the universal-radio filter has. The capacitance across the switch can degrade the overall rejection of the filter by allowing a little bit of signal to bypass the filter itself.
Also be sure to use a good quality jumper cable between the filter and the radio. Last year I noticed detectable signals in the stop band of a LF LPF I was using. It turned out that the jumper I was using was the problem. I replaced it with a different jumper and all was well again. Checking the jumper out on a Spectrum Analyzer I found that the poor jumper degraded the filter stop band by more than 20 dB. When I cut the jumper open I found very poor braid coverage.
Be careful about the 20W in the AMBC. Depending on where they put the LPF cut off frequency, that 20 watts you are reading may be a combination of the fundamental and harmonics.
I used my KX3 to check into a 5 MHz Navy MARS net once (since it was Navy MARS you know that was a few years ago). I did not modify anything for MARS ops, but it is possible that I was only able to do so because the radio was capable of 60 Meter band operation. I never tried it on other MARS frequencies.
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167
VHF/UHF Logs, including satellites and radiosondes / Re: FLTSATCOM
« on: March 06, 2020, 1234 UTC »
FLTSATCOM 8, seen here:
https://www.n2yo.com/satellite/?s=20253
Has an inclination of 13 degrees and you can see much more N/S movement around the suborbital point. It isn’t drifting West like FLTSATCOM 7. My guess is that they are either moving 7 or they no longer have enough fuel for station keeping.
https://www.n2yo.com/satellite/?s=20253
Has an inclination of 13 degrees and you can see much more N/S movement around the suborbital point. It isn’t drifting West like FLTSATCOM 7. My guess is that they are either moving 7 or they no longer have enough fuel for station keeping.
168
VHF/UHF Logs, including satellites and radiosondes / Re: FLTSATCOM
« on: March 06, 2020, 1226 UTC »
One other thing. It might seem like an inclined orbit is a negative thing for a Geo, and often it is, but it is sometimes useful. On the satellites farthest excursions North/South, it may be visible for a little while to earth sites at high latitudes that normally would never be able to see geo satellites.
169
VHF/UHF Logs, including satellites and radiosondes / Re: FLTSATCOM
« on: March 06, 2020, 1213 UTC »Well I'm confused then because when I plug the latest keps into Orbitron it shows FLTSATCOM 8 as stationary over India near its equator moving slowly S-N every day. If I plug FLTSATCOM 7 in, it shows it over Hawaii -- but every day it shifts west-ward along the equator. UFO 5, 6, and 9 are similar.
OK, that sounds like FLTSATCOM 8 is in a slightly inclined orbit, doing the figure 8 stuff.
Is it possible FLTSATCOM 7 is being moved? To shift an orbital slot, the satellite is moved slightly closer to or farther from earth. That causes it to move East or West. When it gets to its new orbital slot, the satellite is parked back into the geo orbit. This uses fuel so it is not done often.
FLTSATCOM 7 is old. I suspect that it is just in an inclined orbit.
If you look here:
https://www.n2yo.com/satellite/?s=17181
You will see that it has an inclination of 14.5 degrees, which is a lot for a geo.
UFO8, seen here:
https://www.n2yo.com/satellite/?s=25258
has an inclination of 8.6 degrees. There will be motion about the suborbital point, but not as much as for FLTSATCOM 7.
Compare the motion along the suborbital point for each of them.
If you compare this to, say, DIRECTV 15, as seen here:
https://www.n2yo.com/satellite/?s=40663
you will see an orbital inclination of 0 degrees and a sub orbital point that doesn't move. This satellite has Ka band transponders and a user base that does not have tracking antennas. It must stay in position, otherwise it will move outside the mainlobe of the user antennas. More fuel will be expended to keep that satellite in position.
170
VHF/UHF Logs, including satellites and radiosondes / Re: FLTSATCOM
« on: March 06, 2020, 0958 UTC »FLTSATCOM uses geostationary satellites...there is no “pass”...either your location is in the footprint or it isn’t.
Are you 100% sure about this? FLTSATCOM 8 appears to be geo but FLTSATCOM 7 appears to be in an equatorial orbit.
Geostationary orbits are a form of equatorial orbit.
FLTSATCOM 7 is in a geo orbit.
https://space.skyrocket.de/doc_sdat/fltsatcom-2.htm
Maintaining a geo satellite with a near zero orbital inclination uses up station keeping fuel. One tradeoff the designer has is to allow small amounts of inclination (for example +/- 5 degrees) to develop. Doing this means you don’t have to perform station keeping maneuvers quite so often, saving fuel and extending the lifetime of the satellite.
To the observer on earth, this results in the satellite apparently “wandering” slightly in the sky, drawing a figure 8 pattern on the suborbital point on the earth. Maintaining a bore site on the satellite would require a simple antenna tracking mechanism, but the beamwidth of most directional UHF antennas is broad enough that this isn’t necessary. On Ka band it would be.
FLTSATCOM 7 and 8 are beyond their planned lifetime. I wouldn’t be surprised to if a decision had been made to leave them in place as long as they were working, but to allow them to develop some orbital inclination.
When a geo satellite is “retired” it is placed in a graveyard orbit. This requires less fuel than deorbiting the satellite. The satellite is pushed a few 100 km farther out than the geo orbit and left there. This frees up that geo slot for another satellite.
Also, you are talking about FLTSATCOM 8, not UFO8, right?
171
Longwave Loggings / Re: New to longwave
« on: March 05, 2020, 1057 UTC »
Thanks. At least I know he is still alive. I still didn’t get a response to my latest email. I will calling him next.
I hope you like the filter.
I hope you like the filter.
172
Longwave Loggings / Re: New to longwave
« on: February 28, 2020, 1256 UTC »
Thanks. I will try contacting him again.
173
Longwave Loggings / Re: New to longwave
« on: February 27, 2020, 1133 UTC »
Please let me know if you get a response from Rescue Electronics. They didn’t answer an email I sent them a few months back (as I noted earlier). You should be safe with a Paypal purchase as you can get your money back if he doesn’t respond. The filter does work well.
The owner is W1VLF, who has several useful Youtube videos available.
The owner is W1VLF, who has several useful Youtube videos available.
174
Equipment / Re: NEMP Rated surge arrestor
« on: February 24, 2020, 0301 UTC »
The isolation capacitor in series with the center conductor is large enough for VHF and higher, but not for HF.
175
Equipment / Re: Spitfire Am transmitter
« on: February 23, 2020, 1314 UTC »
Outdoor unit:
http://talkinghouse.com/range-extender-2.5.htm
https://www.hobbybroadcaster.net/reviews/iss-range-extender-2.5-talking-house-iam-radio.php
The antenna tuner in the outside unit looks a lot like that used in the inside unit (https://images.app.goo.gl/BMwyMH8ZS4LTTBT99).
I don’t know if they actually put the final amplifier outside or not.
Note the patent links on this page. They provide an explanation of how it works.
http://www.prc68.com/I/TalkingHouseTransmitter.html
http://talkinghouse.com/range-extender-2.5.htm
https://www.hobbybroadcaster.net/reviews/iss-range-extender-2.5-talking-house-iam-radio.php
The antenna tuner in the outside unit looks a lot like that used in the inside unit (https://images.app.goo.gl/BMwyMH8ZS4LTTBT99).
I don’t know if they actually put the final amplifier outside or not.
Note the patent links on this page. They provide an explanation of how it works.
http://www.prc68.com/I/TalkingHouseTransmitter.html
176
Equipment / Re: Spitfire Am transmitter
« on: February 23, 2020, 1300 UTC »
As I remember, the amplifier and matching network are out at the antenna. The coax merely brings a low level RF signal from the indoor unit to the outside amplifier. So rather than put everything in one box, they split it into two.
177
Equipment / Re: NEMP Rated surge arrestor
« on: February 23, 2020, 1246 UTC »
The frequency limits they show are real too. I saw an installation where the installers used similar surge supressors for the HF antennas. The antennas were dead as a door nail. Replacing the supressors with ones rated for HF made everything good again.
178
Longwave Loggings / Re: New to longwave
« on: February 23, 2020, 1235 UTC »Would it be this filter? Or is this an old model?
https://www.universal-radio.com/catalog/filters/1143.html
A lot cheaper.
I have one of those. It works, but the one I have from www.rescueelectronics.com works a little better.
I would recommend caution with the bypass switch that the universal-radio filter has. The capacitance across the switch can degrade the overall rejection of the filter by allowing a little bit of signal to bypass the filter itself.
Also be sure to use a good quality jumper cable between the filter and the radio. Last year I noticed detectable signals in the stop band of a LF LPF I was using. It turned out that the jumper I was using was the problem. I replaced it with a different jumper and all was well again. Checking the jumper out on a Spectrum Analyzer I found that the poor jumper degraded the filter stop band by more than 20 dB. When I cut the jumper open I found very poor braid coverage.
179
Longwave Loggings / Re: eLoran 100 kHz 1252 UTC 20 Feb 2020
« on: February 20, 2020, 1426 UTC »
Good signal in Midland 1423Z. Note that the KiwiSDR has a decoder built in as an extension. GRI is 8970.
180
Equipment / Re: Any Elecraft KX3 owners?
« on: February 18, 2020, 1035 UTC »A lot of kx3 owners I know of are selling their kx and getting these things;
https://www.youtube.com/watch?v=gwHbZasHleQ
Simple one diode-ectomy to enable wideband tx, and they nicely placed a rather obvious arrow pointing at the diode to dissect. 20w even on ambc plus a transmatch that will match shorts to opens. Draws about 500 mils on rx with screen off.
Be careful about the 20W in the AMBC. Depending on where they put the LPF cut off frequency, that 20 watts you are reading may be a combination of the fundamental and harmonics.
I used my KX3 to check into a 5 MHz Navy MARS net once (since it was Navy MARS you know that was a few years ago). I did not modify anything for MARS ops, but it is possible that I was only able to do so because the radio was capable of 60 Meter band operation. I never tried it on other MARS frequencies.
