I wasn't gonna say anything but!You got to admit though, that there Star Gun shore is a purty antenner.
I think DJBoutit needs 4 of those on his bread box on wheels.
"To get a Standing Wave Ration of "1 : 1" both the antenna and the coax must have an impedance of 50 ohms."
This is simply untrue if the point of measurement happens to be at a null voltage point in the line (usually multiples of 1/2 wave). There is no "line" SWR, only point of measurment SWR.
I think you may be referring to VSWR.
There are fairly sharp null points of voltage standing on a poorly matched transmission line.
But the current standing at the same point is opposite: it peaks at the voltage null point.
Maybe its better not to think of antenna/coax mismatch that way.
I think it better to think of it in the context of return loss, which is specified in dB.
For example: an SWR of 3 is same as a 6dB return loss, meaning that the power reflected back to transmitter is 6dB down from the transmitter "forward" output power. Another swr, such as 1.2 is a 20dB return loss.
Return loss does not change depending on coax length, except for the coax insertion loss which is small for CB frequencies.
PS: an SWR of 1 is actually physically impossible. nothing in this world is perfect.
Pity the site owner doesn't understand AM swing though,for 100% modulation you will see 6 watts forward swing,not 8 watts on an average reading meter and just under 16w pep on a peak reading meter.
Incoming Region Produces X3 Solar Flare |
May 15, 2024 @ 14:55 UTC |
Another major solar flare, but this time from an active region just beginning to turn into view off the east limb. It is possible that the group responsible is old AR 3654 from the previous rotation. The latest flare, an X2.99 event just peaked at 14:38 UTC (May 15). Stay tuned |