Amateur Radio Stack Exchange
Amateur Radio Stack Exchange

Questions tagged [satellites]

Amateur radio satellites refer to any artificial object in Earth orbit that are useful for amateur radio purposes.

This tag covers all amateur radio communications with man-made Earth-orbiting objects, including communication over dedicated amateur radio satellites (AMSATs) and with astronauts aboard a space station such as the International Space Station (ISS).

It does not cover reflecting signals off passive, natural objects such as Earth-Moon-Earth communications (EME) or meteor scatter.

115 questions
22
votes
3 answers

Can I build a radio telescope out of a parabolic TV satellite dish?

I have the possibility to buy a very inexpensive 2.4m parabolic satellite dish and I would like to build a radio telescope from it. Originally this dish was designed to be a satellite TV antenna. Can I replace the TV LNB with radio receiver tuned…
SP5RFD
  • 323
  • 2
  • 6
12
votes
1 answer

Who funds amateur radio satellites?

I am currently studying for my Technician Exam and I am amazed at the sheer number of amateur radio satellites in orbit. Knowing how expensive it is to launch something into space, and assuming there is very little return on investment concerning…
Dave G
  • 295
  • 1
  • 9
11
votes
2 answers

Why do satellites receive and transmit on different bands?

Most satellites I've found transmit on VHF and receive on UHF or vice versa. Why is this? I would think there's enough space on a single band.
Skyler 440
  • 7,550
  • 7
  • 48
  • 88
11
votes
4 answers

How do GPS receivers communicate with satellites?

I have a Technical Amateur Radio license so I know the basics of wavelengths. What I'm researching is how GPS works. From what I've read, there are frequencies such as L1, L2, and L5 uses in GPS between the receiver and the satellite. These operate…
john_ham_radio
  • 309
  • 2
  • 5
11
votes
1 answer

Why would you need a signal generator to receive early satellite transmissions?

I recently watched, on You Tube, a NOVA program about the British school masters and students who were the first to publish the news that the Soviets had started launching satellites from a new launch site back in 1958. (School Boys Who Cracked the…
John Warren
  • 213
  • 1
  • 4
10
votes
2 answers

APRS digi path for ISS digipeater?

So when I try to work the ISS digipeater, what should I set the digi path to be? My setup is a 5 W HT with a 2 m yagi connected to my phone with APRSDroid. I've tried the past few nights with ARISS R0ISS and WIDE2-2 and none seem to get picked up…
JW03
  • 103
  • 1
  • 4
10
votes
3 answers

Calculating Doppler Shift for satellites

If I know how fast a satellite is moving through space, how can I calculate the doppler shift for the pass?
Skyler 440
  • 7,550
  • 7
  • 48
  • 88
9
votes
2 answers

Can there be (long range) propagation of HF from satellites?

HF transmissions from the ground can be reflected by the ionosphere leading to very long distance propagation. Satellites in low Earth orbit (160 km to 2,000 km) fly within the ionosphere (60 km to 1,000 km); with the F layer at 150 km to 500+…
DarcyThomas
  • 273
  • 2
  • 9
9
votes
2 answers

Are satellites Left or Right hand circularly polarized?

I'm thinking of building some helical antennas for satellite work. I want to know which way to wind them. If satellites are spinning randomly, how can we know if they are left hand or right hand polarized or Which way do I wind my antenna
Skyler 440
  • 7,550
  • 7
  • 48
  • 88
8
votes
2 answers

Have hams ever used (clusters of) geostationary satellites as passive microwave reflectors?

A number of geostationary satellites are quite large and/or appear in clusters. Moreover, many of them have large reflectors pointing to Earth (e.g. satellite TV sats). Finally, these satellites are located at roughly $\frac{1}{10}$ the distance…
on4aa
  • 1,277
  • 9
  • 22
8
votes
2 answers

cubesat turnstile antenna material selection

My cubesat team is working on our design for rolled whip antennas to deploy in a UHF turnstile configuration based on this design: What I would like advice on is the material for the antennas themselves. Spring steel has ideal mechanical…
Kontakt
  • 155
  • 7
8
votes
3 answers

What gain do I need to talk to SO-50 with my HT?

My HT has 5 W of power, a sensitivity of about 0.2 µV, and I would like to talk to the SO-50 with it. How much gain do I need in my antenna to make this work?
PearsonArtPhoto
  • 6,158
  • 2
  • 31
  • 61
8
votes
2 answers

What will I need to receive the ICE/ISEE-3 transmitter?

The ICE/ISEE-3 spacecraft, launched in 1979, is due to pass by the earth in August, 2014. It was commanded to power down completely years ago, but it appears to have failed to do so, and while it could be re-tasked to perform another mission…
Adam Davis
  • 12,095
  • 2
  • 45
  • 106
7
votes
1 answer

How to talk to the ISS

I have a UHF/VHF transceiver capable of transmitting on UHF and receiving on VHF or vice versa on channel mode. I finally got a directional Yagi antenna so reception/transmission shouldn't be a problem. I live in Colorado, USA. Which frequencies…
Skyler 440
  • 7,550
  • 7
  • 48
  • 88
7
votes
3 answers

Store-and-forward capable satellites in operation?

The amateur satellite community used to have a small fleet of pacsat satellites (AO-16 and friends), which were capable of store-and-forward message passing: you could upload messages to the LEO satellite on one side of the world, and download the…
oh7lzb
  • 2,361
  • 1
  • 14
  • 38
1
2 3 4 5 6 7 8