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. …
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: …
Coaxial Folded Dipole Antenna Matching Impedance
Apr 22, 2015 · The site above depicts a regular dipole, with a simple matching system. First, a bit about dipole impedance. The impedance of a dipole is 73 Ohms at resonance, but away from the resonant …
Antenna tuning confusion - help! - Amateur Radio Stack Exchange
Aug 21, 2023 · A dipole antenna in free space ( no ground effects like capacitance or wire resistance) is 73 ohms. So if you had a dipole, @ a specific frequency, terminated into a 1/2 wavelength (electrical) …
Understanding how antenna mismatch can damage a transmitter
Nov 1, 2023 · Antenna impedance is largely due to radiation resistance: a center fed half wavelength dipole has a radiation resistance of about 73 ohms. Resistance due to heat loss is negligible, and I …
What is the impedance of an end-fed half-wave antenna?
Model the 1/2 wave center fed antenna using the wire size, altitude, and all location attributes to determine the center fed impedance. divide 600 by the 73 ohms or whatever you calculate the center …
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 would be the typical received power of an "S9" signal?
The Wikipedia S Meter article cites: IARU Region 1 Technical Recommendation R.1 defines S9 for the HF bands to be a receiver input power of -73 dBm. This is a level of 50 microvolts at the receiver's …
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 …
IC-7300 internal tuner failing when before tuning I have a 1.5:1 SWR?
Nov 21, 2022 · I have an IC-7300 and have tried it with a couple of antennas. In each case the internal tuner works sometimes, and not others. That is not a surprise in itself, but sometimes when the …