Questions tagged [microwave]
Questions related to operating on frequencies above 902MHz.
4
votes
1answer
72 views
How to create a simple 1296MHz transmitter?
I have asked this quesion on other sites, but want to try to repeat it here. Also I have asked question about multiplier, and this is a different question.
I discovered a 1296MHz beacon in my city ...
5
votes
1answer
48 views
What is the best approach for measuring return loss of a home-made 3cm horn?
Let's assume I have built a SMA-to-waveguide transition that flares out into a horn antenna. There's no flange between transition and horn, it's made of a single metal sheet. The antenna has tuning ...
1
vote
1answer
57 views
RF inert adhesive for building antennas in the UHF to low GHz region
I want to experiment with different mechanical designs for some Yagi antennas for 440 MHz through perhaps 2.3 GHz. I am looking for some adhesives and/or potting-like materials that would be ...
2
votes
1answer
1k views
Why are FM radio waves less susceptible to interference than AM?
When studying modulation of radio waves (or of most electromagnetic waves for that matter) I came across this question:
Why are FM waves less susceptible to interference than AM waves?
I know that ...
0
votes
1answer
1k views
How to calculate Return loss of cascaded system?
If system 1 has 10 dB return loss and system 2 has 20 dB return loss then what is the overall return loss of cascaded system of 1&2 ?
8
votes
1answer
740 views
Faraday cage in Microwave oven
If I put my mobile phone in my microwave oven and close its door,
Should I be able to get incoming calls ?
Because, I tried it and I was able to get calls, what does it mean?
Does my microwave oven ...
1
vote
1answer
39 views
Picostation Not Accepting AREDN Firmware
Help! I got a PicoStation off of Ebay. When trying to upload the Amateur Radio Emergency Data Network firmware to it, I get Bad firmware update image. How do I get ...
4
votes
1answer
193 views
How far the near-field reactive region extends from the transmitting antenna?
I am doing research on near-field harvesting. In my situation the transmitting antenna is a dipole antenna operating at 2.45 GHz and its length is 14 cm long. I am trying to find how far near-field ...
6
votes
3answers
262 views
What is this large, flat microwave coaxial connector?
I picked up a random piece of RF hardware at a flea market. I'd like to know what these unusual connectors on it are.
The jack is flat on its face except for the gold ring. Inside the gold ring ...
2
votes
1answer
1k views
How to build the smallest directional antenna (ISM band)?
What kinds of configurations should I try when trying to make the physically smallest 2.4 GHz (ISM band) antenna that is significantly directional front-to-back. "Smallest" meaning in in cm maximum ...
1
vote
1answer
176 views
why fiber optics replaced microwave [closed]
I was recently reading an article where they mentioned about abandoned microwave towers being replaced by fiber optics.
From what I understand microwave technology is better at speeds, is cost ...
4
votes
1answer
221 views
What is a general procedure for aligning directional antennas?
I want to establish a microwave link (1.2GHz) between two stations using antennas with a directional radiation pattern. The stations have a clear line of sight to each other. Each antenna is attached ...
2
votes
2answers
273 views
Linksys WRT54G turned in to a brick
I just bought my first WRT54G (V3), and wanted to build a mesh network (Using the Broadband-ham firmware, http://www.broadband-hamnet.org/ , which as I understand is based on OpenWrt). I wasn't paying ...
7
votes
2answers
321 views
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 ...
7
votes
1answer
227 views
What is a good way to bench test a mesh network?
I've been experimenting with some 2.4ghz based mesh networks similar to http://hsmm-mesh.org/. I'd like to have something on the bench where I could simulate roving between nodes, and create hidden ...
