Why do hams often conclude messages with "73"?
Oct 25, 2013 · The usage of "73" for such a purpose comes from the Phillips Code, originally devised in the era of telegraphs to speed up transmission of common messages by mapping them to numbers. …
jargon - CB v Amateur Radio - Amateur Radio Stack Exchange
Aug 16, 2021 · I am learning about Amateur Radio so as I can go for my foundation licence but I was on CB back in the days, a channel nine monitor and used the 10 code and the Q code but all I can see …
digital modes - How do you log (or not) "busted" FT8 QSOs? - Amateur ...
Oct 24, 2021 · Since it is "technically" a complete QSO I log it (in DXKeeper) but don't upload to e-qsl or LotW unless the other party does. If he does, I'll upload: if he doesn't I assume he has it as …
CW: when I supposed to send "E E"? - Amateur Radio Stack Exchange
Jan 8, 2020 · I'm new to CW and one thing I couldn't figure out is when I supposed to send "E E". Let's say I'm calling CQ and somebody answers me. The QSO is almost over. Should it be ended like this: …
What is the impedance of an end-fed half-wave antenna?
Theoretically, (73 + j42.5)Ω. When the dipole is too short, its reactance will be capacitive. When it's too long, inductive. Since the exactly half-wave dipole has a slightly inductive reactance, shortening it …
Core mix preferences for a balun (or unun) vs a choke
May 10, 2022 · The MnZn ferrite cores (Mix 31, 73, 75) have high permeabilities above 800 µ, have fairly low volume resistivity and moderate saturation flux density. They offer high ‘Q’ factors for the 1 KHz …
What's the difference between saying “CQ” or “QRZ” in a contest?
The best thing to do is to listen for a while, and notice which stations are being responded to. Sometime operators will prematurely respond with their callsign, without waiting to hear if the other station has …
procedure - CW contact content - Amateur Radio Stack Exchange
Jan 11, 2015 · In the end, we have 73, which is commonly used. Then there's the procedural part. I send SK, meaning that I'm ending the conversation and I send CL, meaning that I'm closing down my …
How to estimate a dipole feedpoint impedance? - Amateur Radio Stack ...
An ideal dipole, at resonance, will have an impedance around 73 ohms. A folded dipole, around 280 ohms. How can I calculate the impedances when not at resonance? Let's assume I have a span of …
Antenna matching for a dipole - Amateur Radio Stack Exchange
Apr 5, 2025 · The question is whether the approach is OK or am I violating the design for dipole? The two elements of dipole are around 6cm away from each other. I am following 50ohm matching until …