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1500 questions
5
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4 answers
What is ham radio?
What is ham radio? (or, more commonly, What are those antennas on your car for?)
I know what ham radio is, of course, but I have a hard time explaining it to people who are not familiar with it. Assume the asker has a typical consumer-level…
kj7rrv
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5
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Would it be possible to transmit all CTCSS tones at once?
What happens if all CTCSS tones are transmitted at once? Would it trip all radios listening on that frequency?
Richard Hum
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5
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4 answers
Can I float an SLA 12v battery at 13.8V forever?
I am considering a battery-backup power source for a radio. Typically, power would be supplied through a standard 13.8V power supply, so the battery would be available if mains power goes out:
AC -> 13.8V linear supply --+--> Radio
…
KJ7LNW
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Can my small ham radio antenna interfere with WiFi in my RV park?
We live full time in our RV. We are at an RV park for the winter. They just knocked on my door and asked what kind of antenna I have on top of my RV. I told them it's a small ham radio antenna that I use only for monitoring at this time. I was told…
pris
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5
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3 answers
Is possible to make small HF microstrip or helical antenna by using high permittivity dielectric material?
Is possible to make small HF microstrip or helical antenna by using high permittivity dielectric material like SrTiO3 ?
abduoman11
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5
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1 answer
maximum acheivable range on CB radio by ground wave?
I have 10 watt CB radio system & 0.64 lambda monopole antenna , I think it has a 5 dBi gain .
what is the maximum acheivable range by ground wave in an urban area ?
If I want to increase my range without increase the system’s power , can I make …
abduoman11
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5
votes
1 answer
How to properly simulate a crystal filter being pulled?
After reading k1zmt's answer to the question of how to change the resonant frequency of a quartz, I wondered how to simulate a quartz filter to check that result.
I went with the following model of a simple quartz filter:
The "loop" in the center,…
Marcus Müller
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5
votes
2 answers
What is this (dangerous) connector type that looks like SMA?
At a hamfest, I recently bought a few RF adapters that I thought were BNC to SMA:
However, when I tried to use one, it ended up destroying the SMA male plug on the cable I attached to it. It pushed the pin out of the housing!
When I looked more…
user3486184
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5
votes
2 answers
Metal panels in 4nec2
I have a number of immovable metal roofs that are near my antennas. I'm wanting to model how these affect my antenna performance.
Is there a way I can put a metal plane into my models on 4nec2?
David Findlay
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5
votes
1 answer
Checking if the frequency is in use for digital modes
On CW and phone, we are taught to ask if the frequency is in use before calling CQ. Is it correct to say that with digital modes, that is impractical, and you should just listen (over the bandwidth you plan to use) and if you hear nothing, just…
gschro
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Are there any stations other than W1AW that fall under 47 CFR 97.113(a)(3)(iv)?
47 CFR 97.113(a)(3) normally prohibits amateurs from transmitting
[c]ommunications in which the station licensee or control operator has a pecuniary interest, including communications on behalf of an employer.
However, 47 CFR 97.112(a)(3)(iv)…
Someone
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5
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Is the Kawamall DMTF 6pin microphone usable with the Kenwood TK-805D radio?
I have a Kenwood TK-805D commercial radio, which I am using for UHF ham operation.
For repeater usage, with AllStar, IRLP, and Echolink, I need a DTMF mic for it.
I did a search on the internet, and found this pinout:
The diagram claims that the…
Skyler 440
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5
votes
2 answers
Antenna tuning confusion - help!
In a recent discussion with a fellow ham about where to use a RigExpert antenna analyzer for tuning an antenna for minimum SWR, we couldn't decide if "antenna only" or "feedline+antenna with the analyzer at the transmitter end". For example, if I…
K4JUL
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5
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1 answer
What's the protocol when making a call on the ISS repeater?
I have mostly only used non-crowded 2 meter repeaters, but recently I tuned my radio to the downlink frequency: 437.8 mhz while the ISS was passing overhead - just to listen.
What I heard was people calling out their call signs in phonetic alphabet,…
scm
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5
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2 answers
Cannot connect Quansheng UV-K5(8) with programming cable
I bought a Quansheng UV-K5(8), and I am impressed by the audio quality, there appears to be a better ratio of signal to noise out of the speaker on listening, and it's a nice little radio, though with some quirks.
I also bought a Baofeng programming…
spl
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