ISS & Satellite Communication
- Thread starter KF0SOP
- Start date
BC_Scan
Member
how do you know ?, there are all kinds of example of on line of handheld LOW POWER with correct antenna pointed at ISS when above and people make it thru, I think like all things as in contesting 100 people are yelling into radio when ISS is overhead , the operator becomes overwhelmed with all kinds of signals hitting his station , it might become a situation where they only pick the intelligible ones vs in the weeds, keep trying test your station with another ground station on simplex to ensure you are above board .
Ok! Thanks! I'm not too experienced an operator, so I haven't gone through all the ins-and-outs, so I'm just going off of what my friend suggested. I have gotten multiple contacts on other stations around KC, so I know my radio's working, and I'll prob just have to keep trying
Are you hearing the repeater aboard ISS? Reason I ask is that the astronauts onboard ISS very seldom "get on the radio". If they do it is usually for events that are scheduled with schools and on frequencies that are not publicized. HOWEVER, you should be able to easily hear the amateur radio repeater aboard the ISS. It has a 25 watt output, which is more power than any of the hamsats that are up there now. I hear it on my base scanner whenever there is an overhead pass, and usually can hear it on a handheld scanner with just a rubber duck during an overhead pass. It is a BIG signal. The downlink frequency is 437.800 mHz (FM mode) and you should be able to hear it easily on any overhead pass. The uplink frequency is 145.990, but for that you'll likely need a directional antenna aimed at the ISS during the pass. It's a standard FM repeater so you'll be hearing other stations on earth... NOT hams aboard ISS.
rf_patriot200
Active Member
Do you have the ISS app on your phone ? That will help you to track it when it goes over your area, so you'll know when to listen for it.
Last I heard you need a 67pl squelch code just on the uplink VHF frequency.
rf_patriot200
Active Member
Yes, on 145.990 to reach the repeater.
wtp
Member
KF0SOP,
i sent a PM with some stuff, look to the top right of this page.
i sent a PM with some stuff, look to the top right of this page.
wd9ewk
Member
Scheduled events use uplink frequencies that are not publicized. The downlink frequency for those events is 145.800 MHz, and anyone within the footprint of those contacts is welcome - and encouraged - to listen in.
The cross-band repeater runs at 5W - still stronger than any other amateur satellite, and protects the ISS radio from overheating. Packet runs at 10W - a little more power, since the digipeater won't transmit for long periods of time. Scheduled contacts using the 145.800 MHz downlink, or any unscheduled contacts using the old split-frequency setup in the 2m band (145.200/145.800 for ITU Region 1, 144.490/145.800 for the rest of the world - this hasn't been used for a few years) where the crews are on the mic, are at 25W. The power settings are built into the customized firmware for the ISS radios, a pair of Kenwood TM-D710Gs (one in the Russian service module used normally for packet, the other in the European Columbus laboratory module normally used for the cross-band repeater).
I was on an ISS pass this evening, using a 5W Kenwood TH-D75 and an Elk handheld dual-band log periodic antenna. I made contacts using packet and FM during that pass - packet contacts using APRS messages to and from a specific station through the 145.825 MHz packet/APRS digipeater, followed by an FM voice contact through the cross-band repeater. The repeater was busy, and the digipeater wasn't too busy. The packet contact took little time to complete, and not much more time was needed for the voice contact. Fun!
Good luck!
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