ISS using 145.800 for RX/TX?????

[spdfile1]

Okay last week the wife and I were driving around near our home in south florida and had the kenwood "a" side on 145.800. We hear Col. Wheelock talking and tried to talk back to him on 437.800 but he never responded. Come to find out an old friend got thru to him as I recognized his callsign. Upon talking to another friend who talked to the friend who talked to Col. Wheelock he stated he was using simplex!!!! I always thought the uplink was on 437.800 but can both the downlink & uplink be 145.800?????

 

[kma371]

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The US uplink for 145.800 is 145.200. The UHF uplink your talking about is for repeater mode.

http://www.issfanclub.com/frequencies

 

[ff-medic]

I live in WV. Anytime the ISS flys over, I always hear , what sounds like a data packet transmission on 145.800 ; I never hear a voice transmission at all . I have numerous freqs in my scanner for the ISS, both vhf as well as uhf programmed.....and the only radio traffic I hear is on the 145.800....agtain ; it sounds to be a data transmission from a computer packet. ---- > Hmmmm

What freq do they talk to school students on? Is there a uhf downlink for NASA?

FF-Medic !!!

 

[spdfile1]

kma371,

Thanks for the info. I will monitor 145.200 along with the others and see what I hear.


ff-medic,

Thats a good question!! I know issfanclub.com posts a bunch of different frequencies used for various things by the iss but I don't remember one labeled for being used to talk to school kids. I have heard of them doing that though. Hopefully some can shed some light on the issue.

 

[JeremyB]

The usual uplink for crew contacts is 144.49 for North and South America

There has been some simplex operation on 145.800.
voice on simplex 145.800 | ISS Fan Club
The ISS Packet repeater is on 145.825

I think they use a few ground stations for their school contacts, I have heard the term telebridged used frequently during discussion of school contacts. I know for even the highest overhead passes, I can only receive the ISS for maybe 10 minutes but it might be good enough for a school contact

 

[gewecke]

The usual uplink for crew contacts is 144.49 for North and South America

There has been some simplex operation on 145.800.
voice on simplex 145.800 | ISS Fan Club
The ISS Packet repeater is on 145.825

I think they use a few ground stations for their school contacts, I have heard the term telebridged used frequently during discussion of school contacts. I know for even the highest overhead passes, I can only receive the ISS for maybe 10 minutes but it might be good enough for a school contact

I think you mean 145.490mhz.Nfm
n9zas

 

[DiGiTaLD]

The usual uplink for crew contacts is 144.49 for North and South America

Correct. The downlink is the same worldwide, however the uplink frequency varies by ITU region. I have worked him using this configuration from Indiana with little trouble using my regular 2 meter base station setup which consists of a Cushcraft ARX-2B at about thirty feet connected to a Yaesu FT-2600M. Nothing fancy there.

Obviously an azimuth-elevation beam setup such as one would use to work satellites would be much better, and you could track the station as it passes, and if you can compensate for Doppler shift, it is great, but ISS can be worked with a regular old base station set up for terrestrial communications, or even a mobile, as I have heard him acknowledge some mobiles as well. When you're that high up, you're going to hear pretty much everything.

 

[kma371]

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The usual uplink for crew contacts is 144.49 for North and South America

There has been some simplex operation on 145.800.
voice on simplex 145.800 | ISS Fan Club
The ISS Packet repeater is on 145.825

I think they use a few ground stations for their school contacts, I have heard the term telebridged used frequently during discussion of school contacts. I know for even the highest overhead passes, I can only receive the ISS for maybe 10 minutes but it might be good enough for a school contact

145.800 is still used as a downlink for school contacts. They are telebridged through IRLP or Echolink from the school to the ground station who is actually within TX/RX range.

 

[spdfile1]

I appreciate everyone's response. That is what I was looking for was different opinions. I just talked to a friend this afternoon who advised he talked to the iss station this morning and they were using 145.800 simplex. He even asked them why they don't use the uhf frequency much and they replied it just gets to busy so it is easier for them to recieve & transmit on 145.800. So there you have it.

 

[kg4ciu]

I think you mean 145.490mhz.Nfm
n9zas

thats not right145.490 is a earth bound repeater out-put I know We operate a repeater there!!

 

[CalebATC]

I appreciate everyone's response. That is what I was looking for was different opinions. I just talked to a friend this afternoon who advised he talked to the iss station this morning and they were using 145.800 simplex. He even asked them why they don't use the uhf frequency much and they replied it just gets to busy so it is easier for them to recieve & transmit on 145.800. So there you have it.

The UHF freq as said earlier, is for when it is in repeater mode.

"What frequencies are used for ISS contacts?-

The following VHF frequencies are used for contacts with the ISS.
Voice Downlink: 145.80 MHz (worldwide)
Voice Uplink: 144.49 MHz (regions 2 and 3), 145.20 (region 1)
Packet Uplink: 145.825 MHz simplex (worldwide"

Note, that you should NOT use the 145.8 for uplink. Although I have heard rumors they are monitoring 145.8 for some problems with their radio. But, use 144.49 unless advised.