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Baofeng UV 9R Handheld programming

I have a Baofeng UV 9R Handheld that I just recently bought and received in the mail brand new, however as much as I like this handheld device I am maxed out with frustration as far as manual programming of this device is concerned. Does anyone have…
Sebastian Masters
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Alinco DJ-500T handheld radio will not transmit, why?

Shows the word OFF on screen when PTT is pressed. In settings "TX" is set to on, what am I missing? The manual is no use due to poor translation and general incompleteness.
Kevin
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Practical differences between switching and linear power supplies?

Power supplies for ham radio equipment (and other equipment of course) seem to come in two flavours: switching and linear. The switching gear tends to be cheaper and smaller as well as more efficient. My understanding is that switching supplies…
Jim MacKenzie VE5EV
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Is CW necessary to be competitive in most ARRL contests?

The ARRL hosts many contests throughout the year, and maintains a leaderboard of sorts to encourage competition. Is it possible to rank on any of the leaderboards without knowing or using morse code?
Adam Davis
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What is "Billion Code" for garage door openers from around 1996?

I've been trying to "hack" my garage door using an SDR (LimeSDR) for a high school physics project, and I have run into a snag. When I look at the signal and demodulate it using ASK in Ultimate Radio Hacker (URH), I seem to be getting a signal that…
Ben Newhall
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Why do we distinguish between balanced and unbalanced?

I hear all the time, "you need a balun between your balanced dipole and unbalanced coax to stop the common-mode current" when it seems the proper advice is "you need something to stop common-mode current (full stop)." Sure, attaching a balanced…
Dominick Pastore
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Cell Tower distance measurement

I am developing a hobby project to detect/measure the distance between my cell phone and a cell tower (GSM tower). I am newbie. I don't even know whether this is possible or not. I have following hardware: Raspberry Pi 3 RTL2832u I am planning to…
Avadhana Technologies
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Powering transceiver and SWR/power meter from same supply?

I'm mostly sure this will be ok, but I'd like to confirm. I have a switching power supply (can't remember the model right now, but it's for ham use, 13.8V/30A) and I'd like to power both the FT-857D as well as the power/SWR meter from it. Is there…
Rimio
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How important is the impedance and resonance of a receive antenna?

I'm very new to shortwave radio, as evidenced here: Can an antenna be too powerful for certain receivers? I want to build a longwire receive-only antenna for the HF frequencies. I've been using the source: SWL - Shortwave Listening as a guide, but…
fishfritters
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Lightning strikes nearby and coaxial cable

A direct hit on my home by lightning is very, very unlikely. However, many lightning strikes that hit Earth nearby are by far the main hazard for ham radio gear (in my opinion, after 60 years in the hobby). The huge electromagnetic pulse generated…
user10987
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Will an iron chimney work well as an antenna?

There is an iron chimney near my house that is not used anymore. It is ~15 meters in length and ~0.5 meter in diameter. How good will it be as an antenna for rtl-sdr?
vasili111
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1200 baud packet radio can't communicate

I'm toying with a simple 1200 baud packet radio I built. I'm attempting for it to be compatible with APRS, which uses the Bell 202 signaling, 1200Hz for mark and 2200Hz for space, which I assume map to 0 and 1 respectively. However it's not…
Adam Davis
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Can an antenna be too powerful for certain receivers?

I'm brand new to shortwave radio and have been researching what kind of a receiver to get. I'll use it on the antenna I'll build (longwire, 50-100 feet) for shortwave listening; no transmitting. Right now I have my sights on a Tecsun PL-360 as it's…
fishfritters
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Why should I practice one month before a contest, rather than the week before?

I've seen suggestions that it's better to practice a month prior to a contest, rather than at any other time prior to the contest. What is special about a that time frame that it would be suggested so often?
Adam Davis
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What is Norton's transform?

This article from Itchen Valley Amateur Radio Club describes an interesting technique called "Norton's transform": This results in a negative capacitor, but in a circuit where there are other parallel capacitors which can be combined, the result…
Phil Frost - W8II
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