Why do hams often conclude messages with "73"?
2013年10月25日 · "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 …
How does one read a ferrite datasheet? - Amateur Radio Stack …
Datasheets for ferrite materials are usually filled with incomprehensible graphs with greek letters. For example, Fair-Rite's 73 material: What's a $\mu'_s$ and a $\mu''_s$? What do these …
How to estimate a dipole feedpoint impedance?
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 …
digital modes - How do you log (or not) "busted" FT8 QSOs?
2021年10月24日 · 73 Dave - K1DJE. Share. Improve this answer. Follow answered Oct 24, 2021 at 18:18. Dave Dave. 81 2 2 ...
Understanding how antenna mismatch can damage a transmitter
2023年11月1日 · 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 …
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, …
CW: when I supposed to send "E E"? - Amateur Radio Stack …
2020年1月8日 · First, some history. As I understand it, the "dit-dit" (E E) comes from an old practice. There is a short tune in popular music that was often used to end a musical …
Core mix preferences for a balun (or unun) vs a choke
2022年5月10日 · Manganese-zinc (MnZn) available as Mix #31, #75 and #77 (and others) – work well for common mode chokes Nickel-Zinc (NiZn) available as Mix #43, #52, #61, (and others) …
Are there formulae to calculate capacitance and inductance of an ...
Keep in mind that a center-fed, infinitely thin, physical half-wave dipole in free space has an impedance of 73+j42.5 ohms; many of the calculations in the reference use this as the …
procedure - CW contact content - Amateur Radio Stack Exchange
2015年1月12日 · AA1BBB DE YU1NKA R OK TNX DR BOB FER ALL BT WILL SEND QSLL VIA BURO BURO BT HPE TO CU AGN ES ALL BEST FER U ES UR FAMILY IN 2015 BT TNX …