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31 votes
Accepted

Why do people say, "get a nickel," on repeaters?

"Getting a nickel" is a reference to how metered pay phones work (worked?). You'd put in some coins, make your call, and when the time you'd payed for expired, the phone operator would ...
webmarc's user avatar
  • 4,028
26 votes

Why do amateur radio operators call an RF choke a balun?

"Balun" is a portmanteau of "balanced" and "unbalanced". Anything made to interconnect a balanced and unbalanced load can be called a balun. A common-mode choke (like a ...
Phil Frost - W8II's user avatar
16 votes

What do "QRM" and "QSB" refer to?

I keep these "Q" signals in line with this : QRN is "N"atural band noise ( lightning ) QRM is "M"an-made band noise ( crowded signals ) QSB is "B"utterfly effect from Ionosphere in-stability.
Glen Ellis K4KKQ's user avatar
15 votes

Why are radio frequency ranges aligned on multiples of 3?

The ITU bands are actually delineated along plain powers of ten! They're just hiding a bit. From the description above a table of all the bands on Wikipedia: As a matter of convention, the ITU ...
natevw - AF7TB's user avatar
12 votes
Accepted

What is a "calling frequency"?

A calling frequency is a common channel known to all - this is the channel that anyone can jump onto and say Hi! Or a specific person you know may be monitoring this channel, you can call out to them. ...
Matt Clark's user avatar
12 votes
Accepted

What is homebrew?

Homebrew is (as the name suggests) when you make your equipment yourself, as opposed to buying it. An amateur setup consists of many components - the largest and most complicated of which are a radio ...
Scott Earle's user avatar
  • 4,589
10 votes
Accepted

Why is the band scope called panadapter?

Marcel Wallace founded Panoramic Radio Corp. and details his "Panoramic radio receiving system" in patent US2279151A (1938). Page 2, column 1, line 19 of the patent gives us a clue as to how the ...
Brian K1LI's user avatar
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9 votes
Accepted

In amateur radio conversation, what does "hihi" mean?

It is ham radio laughter. HIHI, sometimes HI, other other times HIHI. It's origins are in CW (aka Morse Code), not voice. In fact, I believe old-timers might think it is silly to say HiHi or ...
K7PEH's user avatar
  • 2,998
9 votes

What is a "roofing filter"?

The roofing filter is the filter through which the first IF must pass. The roofing filter is an IF filter, specifically the first one. AB4OJ provides a block diagram: As for why it's called a "...
Phil Frost - W8II's user avatar
8 votes
Accepted

Is there a special name (and if so what is it) for this flush-style SMA variant?

It is known as an SF style SMA connector. It is also commonly known as a Motorola SMA connector since they seem to be one of the few large scale users of this style connector You can find some ...
Glenn W9IQ's user avatar
  • 18.6k
8 votes

Is a 5 watt UHF/VHF handheld considered QRP?

My personal opinion is that QRP means using significantly less power than is customary for a given mode of operation. In that sense, a 5W HT would not be QRP because pretty much everybody else with an ...
mrog's user avatar
  • 1,023
8 votes

Is a 5 watt UHF/VHF handheld considered QRP?

My understanding of "QRP" is simply the use of as little power as possible to make contacts over interesting distances. There isn't a specific power level that equates to "QRP" - it is more a function ...
Synchros's user avatar
  • 101
7 votes
Accepted

What is a QSL card?

A QSL card is a physical card usually the size of a postcard. They are sent to verify a contact known as a QSL. To get various awards like Worked All States or DXCC (worked 100 entities) you need to ...
Jim's user avatar
  • 1,678
7 votes

What is IQ in the context of SDRs?

"IQ" refers to the practice of having two mixers with their oscillator phase 90 degrees apart, and then the digitization and processing of those two streams of data. One practical problem is in a ...
Phil Frost - W8II's user avatar
6 votes

What is the origin, history behind "Ben's Best Bent Wire"?

In the RAF we used "best bent wire" as a test transmission largely because it has a lovely jazz rhythm. Some put "bens" in front, some put another "bent" on the end, but i you send it a reasonable ...
user8244's user avatar
6 votes

What is a "calling frequency"?

Calling frequencies are defined for specific bands and most common for VHF and UHF and are mode specific (i.e. Weak signal, FM simplex, etc.). In fact, knowing calling frequencies such as 2-meter ...
K7PEH's user avatar
  • 2,998
6 votes
Accepted

Antenna length in relation to lambda length

Terminology can be ambiguous here; there is no universal standard for how to describe antennas. That said, here are some heuristics: If someone says, e.g., “a 20-meter dipole”, they mean an antenna ...
Kevin Reid AG6YO's user avatar
  • 24.5k
6 votes

I was told to check the cluster. What does that mean and how do I do that?

Definition A DX cluster is a venue (a website or Telnet session) where amateurs may post information about the callsign and frequency of a desirable DX station, so that others may see the posts and ...
Mike Waters's user avatar
  • 7,919
6 votes
Accepted

What does CI-V stand for?

CI-V stands for Computer Interface 5 [Roman numeral "V"] and is ICOM's designation for their rig interface to a computer or to another rig. You can find it on most HF and some VHF rigs since the ...
Mike Waters's user avatar
  • 7,919
6 votes
Accepted

What exactly are Gold sequences and how are they used?

Table of contents But what exactly generally is a Gold code? How exactly are they implemented in order to differentiate multiple signals on the same frequency? What Gold Codes are and aren't How ...
Marcus Müller's user avatar
5 votes

What is a panadapter?

A panadapter is a device that adapts the narrow (typically 4kHz) bandwidth of a traditional receiver into a much wider bandwidth, perhaps the entire band. The pan- prefix means all, as in panoramic, ...
Phil Frost - W8II's user avatar
5 votes
Accepted

Repeater identification ending (CW)

The repeater is in Blacksburg according to an internet search, so BBG is almost definitely an abbreviation of that.
hobbs - KC2G's user avatar
  • 12.1k
5 votes
Accepted

How proper HIHI sounds like?

People sending HI tend to fall into two camps. Some people send a correct HI, as if they learned that ...
Scott Earle's user avatar
  • 4,589
5 votes

What is IQ in the context of SDRs?

To just answer the literal question: I stands for Inphase and Q stands for quadrature. These are the two baseband signals you get when you mix the RF signal with a cosine of the carrier frequency, ...
Marcus Müller's user avatar
5 votes

How do you know if you're on a 10 meter band?

Frequency and wavelength of a wave are related: the frequency times the wavelength equals the speed of the wave, in this case the speed of light. For HF, the frequency in megahertz times the ...
rclocher3's user avatar
  • 9,182
5 votes

CB v Amateur Radio

None of the above. There are no "73 codes" like 10-codes, 73 is just 73. Yes, I know about the 92 code, but it's well and truly dead, with no survivors other than 73 and occasionally 88, so ...
hobbs - KC2G's user avatar
  • 12.1k
5 votes
Accepted

How do you make a HF contact?

A “contact” is just positive acknowledgment exchanged between 2 stations. For example: me: CQ CQ CQ from w4pso you: w4pso this is kc3wcr calling, your signal is 59. name here is Anthony, over. me: ...
webmarc's user avatar
  • 4,028
4 votes

What's the difference between saying “CQ” or “QRZ” in a contest?

The answer is very simple: a contest station "running" a frequency calls "QRZ?" because it is faster than calling CQ and giving the call sign. The station running the frequency isn't trying to get ...
rclocher3's user avatar
  • 9,182
4 votes
Accepted

What is RF hash?

Discovered on another thread (eham) that "RF hash" is slang for broadband noise, meaning a) RF interference that has an unusually large bandwidth (continuously spread) or b) covers multiple frequency ...
Noji's user avatar
  • 487
4 votes

How to determine a serial number in cq contest?

Serial numbers usually count from 1 to N where 1 is for your first contact of the contest. Serial numbers are incremented by 1 typically. But, there is no reason why you cannot start at 577 and ...
K7PEH's user avatar
  • 2,998

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