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- Hottest jargon Answers - Amateur Radio Stack Exchange
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
- Why do hams often conclude messages with 73?
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 "73" mapped to "best regards" or "my compliments" and was intended as a general valediction for transmitted messages It is still used for that purpose today in morse code transmissions and often makes its way
- Why does SWR of a dipole decrease the closer it is to the ground?
I presume you are running a 50 Ohm system (radio trasmission line), and while the characteristic impedance, in free-space, of a dipole is ~73 Ohms, at various distances from the ground, the impedance can vary significantly; So using a 1:1 BalUn, as you are, at a certain height you may be close to 50 Ohms, where at other heights you may be closer to the characteristic impedance of 73 Ohms or
- Antenna matching for a dipole - Amateur Radio Stack Exchange
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 balun and after that 73 ohm everywhere Just looking at the two branches of your antenna: I'm not sure I'd say you're "violating" anything, but the model for a "simple" dipole is that the gap between the
- HF SSB etiquette when someone is working quick but not contesting and . . .
When someone is working quickly -- clearly trying to work a lot of stations -- but pretty clearly isn't contesting, what's the etiquette when they 73 you and end the contact but you're not sure the
- How to find or derive the maximum safe input power to a receiver?
Then in order to put it at our supposedly generally-safe level of -73 dBm, we need $-73\:\mathrm {dBm} - 37\:\mathrm {dBm} = -110 \:\mathrm {dBm}$ That much attenuation is probably most conveniently achieved by the approach of putting a dummy load on the transmitter and letting the leakage carry your signal
- How to increase the bandwidth of half-wave dipole antenna?
I have designed a half-wave dipole antenna for frequency range of 150 to 200 MHz Due to resonant frequency of 175 MHz, Its dimensions are: L=817 44 mm, R=1 71 mm Impedance is also equal to 73 ohms
- Why do operators mention the band when calling CQ on phone?
Apart from historical reasons it's also a filler When calling CQ on SSB you probably want to stretch out your transmission a bit because that's what you need to get heard In theory you could just say your Callsign and "CQ", as it is enough information If people would hear each call immediately it would suffice In practise expanding the length of your transmission will increase your chances
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