Amateur Radio Stack Exchange
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1500 questions
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1 answer

Are some ferrites porous enough they should be protected outside?

I recently bought a couple of 61-mix toroids, and as usual I wrote the mix number on them before they become mystery parts. However, the ink soaked right into the ferrite. I've left ferrites hanging out in the weather, getting wet and frozen without…
Phil Frost - W8II
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Which countries require you to change your call sign if you change your residence?

I live in Austria (OE). There we have to change our call sign if we move beyond one of the 9 Austrian federal state's border. For example I lived near Innsbruck (Tyrol) with the sign OE7TKT. I moved to Graz (Styria) for studying - new call sign…
Tom Kuschel
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SSB offset determination?

Is there any algorithmic way to determine if the mixed frequency offset in an SSB SDR demodulator is wrong (too high or low), other than listening for funny sounding voices? (perhaps by checking to see if voiced vowel spectral overtones fall in a…
hotpaw2
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Is a ground plane necessary for transmitting and receiving with a vertical (monopole) antenna?

I've read the post here: https://electronics.stackexchange.com/questions/77256/why-do-some-radio-antennas-require-a-path-to-ground-and-some-do-not which says The antenna system requires a "ground plane" for the radio wave to form. With dipoles, one…
Steve
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What is a shallow/deep QSB?

Probably all amateurs recognize QSB as the q-code to represent 'fading'. I recently encountered the terms Shallow QSB Deep QSB A quick google search failed to yield fruit; What do the above terms mean?
VU2NHW
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How to calculate single-stub match (general case)?

I'm trying to build a 1/2 wave "Coaxial J-Pole" antenna, similar to what is described here: Such an antenna would be great for stringing up in a tree when operating remotely, no tuner needed. The trick is that I'm trying to use 75Ω RG6 coax for the…
Robert Quattlebaum
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Does the wire/conductor size of all the elements affect antenna bandwidth?

Does the wire diameter of the reflector and the directors of a beam antenna affect the bandwidth or is it only the driven element diameter that has this effect?
Mein Tenah
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Are there easier ways to make traps than coax and plastic pipe?

I recently built an antenna for my attic inspired by http://degood.org/coaxtrap/. I found making the coax traps very time consuming and frustrating to tune. I got to thinking about 3D printers, and I've been wondering if there is a better option…
K9KRB
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Pre-transmission burst sent by fldigi

Every time I click on a PSK macro, before transmitting the message, fldigi outputs a burst of something for about a second. This is visible but not readable on my waterfall display. It wastes time and I want to get rid of it.
Andrew Rose
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Which is better in my situation: Balanced dipole, or as much wire as possible in the air?

I'm finally getting to the point of hopefully putting up a HF antenna. The idea is to start with a simple, straight wire dipole using trees as support points. (No traps or coils.) However, with the layout of my property and the location of the trees…
user
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How to ground with little surface area?

Let's say I have a very small device, like an RC airplane, which transmits information as well as receiving commands for control. The body is made out of non-conductive foam, therefore not much ground is available. How can quality transmissions be…
Skyler 440
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In amateur radio conversation, what does "hihi" mean?

A common phrase/word I've seen used in text and I've heard on air in conversation is "hihi" or "hi-hi". What does this mean and in what contexts is it appropriate to use?
user2943160
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How to build a remote control unit that works on amateur radio frequencies?

The only remote control units I have used before was those little cheap 27Mhz puny range cheap units. I would like to build some sort of RC unit, which has a range up to 1km line of sight. I have a general license. How can I get started with remote…
Skyler 440
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How should this SWR meter's directional coupler work?

I'm wrapping up a "home build" of the MFJ-941EK antenna tuner kit and having trouble getting the wattmeter calibrated. I can't use C4 to get the reflected power reading calibrated down to 0 as is supposed to happen. So now I need to figure out what…
natevw - AF7TB
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How to measure a balun for effectiveness?

It seems there are almost as many "balun" designs as there are web pages about "baluns". There's lots of accusations pointed in all directions ("design Z isn't a balun OR a choke", "design Y is overkill", "design X could lead to spurious…
natevw - AF7TB
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