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1500 questions
9
votes
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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
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Why do so many HF transceivers use a UHF connector?
Just looking around at various rigs online for a fiend. Lots of them look really attractive TS-480, K2, K3, FT-450D, FT-950, IC-78, FT-897 to name just a few...
These rigs are mostly HF, albeit some are also VHF/UHF capable. Yet the antenna…
VU2NHW
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9
votes
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What is the procedure to obtain an amateur radio licence in Australia?
What and how would I go about obtaining a licence for HAM radio in Australia?
Do the licencing regulations vary significantly from state to state?
user17
9
votes
1 answer
Antenna size for wideband
I just bought a SDR dongle that comes with an antenna. The dongle is for DVB-T.
The antenna is very small but the specs say that the dongle can go 30Mhz to 850Mhz.
From my knowledge of antenna physical size should be 1/4 the size of the…
Martin Naughton
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9
votes
3 answers
When will my new license appear in the FCC database?
I tested and passed my Technician's test on Thursday, June 4, 2015. Approximately how long will my license take to appear in the FCC database?
Melona380
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9
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2 answers
What causes ground losses in a HF antenna system?
This applies to mobile and fixed installations. What are ground losses, and how can they be minimized? It seems to involve proximity to the ground, but what is the mechanism that causes loss? Does antenna installation height influence ground loss in…
Bill - K5WL
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9
votes
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Antenna modeling on non-uniform terrain
I'm interested in modeling the radiation pattern of wire antennas for hf before I invest the resources necessary to erect the antenna. I'm familiar with tools such as 4nec2, but from what I can tell the ground is modeled as being flat.
However, at…
W5VO
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9
votes
3 answers
How do club codes stay secret?
To use auto patch, IRLP or other special repeaters, you need the club code from the local club I am part of, which is a DTMF code.
But I was thinking, DTMF can't be very hard to decode, and if someone (like an unlicensed guy with a receiver) records…
Skyler 440
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4 answers
2m or 70cm FM mobile radio for digital mode operation
Are there any 2m and/or 440cm FM mobile radios that have audio inputs for supporting digital modes, like PSK31 or SSTV?
I have a Rigblaster that I use with my HF radio so I could get a mike cable and connect it directly to the mike input in the same…
Kevin Hooke KK6DCT
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9
votes
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What privileges do I gain with each addition step of the license (in the UK?)
The UK has 3 licensing levels, foundation, intermediate and advanced. Aside from the allowed power output going up each time (10W, 50W, 400W) are there any other privileges one would gain?
berry120
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9
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1 answer
Advantage of 6 meter repeaters
6 meters seems to be a place where when the conditions are right, repeaters may interfere with each other from far distances, but when the conditions are normal, repeaters are similar to 2 meters.
What is the advantage of installing repeaters on 6…
Skyler 440
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9
votes
4 answers
How can you calculate the frequencies for each band?
I've just started studying for my HAM license a couple of weeks ago, so please excuse me if this is a remedial question...
I have the Canadian Amateur Radio Basic Qualification Study Guide (which I'm finding is terribly hard to understand). Their…
BenAlabaster
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9
votes
2 answers
Is Morse code allowed on FM in the USA
Let's say I get my little 2 meter FM handheld out and make a little sine-wave generator with which I pulse a morse code and if I connect it to headphones a speaker, I hear the dits and dahs of a nice sine wave tone. Now let's say I connect this to…
Skyler 440
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9
votes
1 answer
How does a slot antenna work?
How does a so-called slot antenna work? How can one construct one? What might be the radiation pattern and efficiency compared to a wire antenna?
And, if a small slot antenna "works" at mobile phone cellular and radar frequencies, would a very…
hotpaw2
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9
votes
3 answers
How far does an antenna need to be from metal to avoid problems?
Living in an apartment, I'm struggling to get good antennas set up, especially for HF. Worse yet, I'm not allowed external antennas (but am willing to try something low profile on the balcony), my apartment is built with stucco (with the "chicken…
David KF4MDV
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