BEGIN:VCALENDAR VERSION:2.0 PRODID:-//jEvents 2.0 for Joomla//EN CALSCALE:GREGORIAN METHOD:PUBLISH BEGIN:VTIMEZONE TZID:Europe/London BEGIN:STANDARD DTSTART:20201025T010000 RDATE:20210328T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20211031T010000 RDATE:20220327T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20221030T010000 RDATE:20230326T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20231029T010000 RDATE:20240331T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20241027T010000 RDATE:20250330T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20251026T010000 RDATE:20260329T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20261025T010000 RDATE:20270328T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20271031T010000 RDATE:20280326T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20281029T010000 RDATE:20290325T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20291028T010000 RDATE:20300331T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20301027T010000 RDATE:20310330T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20311026T010000 RDATE:20320328T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20321031T010000 RDATE:20330327T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20331030T010000 RDATE:20340326T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20341029T010000 RDATE:20350325T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:STANDARD DTSTART:20351028T010000 RDATE:20360330T020000 TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:Europe/London GMT END:STANDARD BEGIN:DAYLIGHT DTSTART:20200711T193000 RDATE:20201025T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20210328T020000 RDATE:20211031T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20220327T020000 RDATE:20221030T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20230326T020000 RDATE:20231029T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20240331T020000 RDATE:20241027T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20250330T020000 RDATE:20251026T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20260329T020000 RDATE:20261025T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20270328T020000 RDATE:20271031T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20280326T020000 RDATE:20281029T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20290325T020000 RDATE:20291028T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20300331T020000 RDATE:20301027T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20310330T020000 RDATE:20311026T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20320328T020000 RDATE:20321031T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20330327T020000 RDATE:20331030T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20340326T020000 RDATE:20341029T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20350325T020000 RDATE:20351028T010000 TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:Europe/London BST END:DAYLIGHT END:VTIMEZONE BEGIN:VEVENT UID:b8b8efafc46ddca724baae9f0917b6f4 CATEGORIES:DEFAULT CREATED:20210706T125538 SUMMARY:Second Zoom talk by Barry K3EUI on the NanoVNA DESCRIPTION:LRS Online Club Night Topic: NanoVNA: An Antenna Stethoscope Part 2\nPlease join me tonight to take another look at the Nano VNA.\n What exactly does it measure?  What is calculated?\n \n Are we able to interpret what each of the following graphs are showing about an antenna's performance?\n \n Refl ection Coefficient (magnitude)\n Return Loss (dB)\n SWR\n \n Question:\n Wh ich impedance has the largest SWR value with  50 ohm coax feed line:\n     25+jo,  100+j0,  40+j30,  40-j30\n \n What level of attenuation (dB) in our feed line is "acceptable" ?\n \n Then Resistance, Reactance, and Impedance :  what do these mean?\n When operating off the resonant frequency, which c hanges faster: resistance or reactance?\n \n How can we correct a reactance (at the antenna)?\n How can we correct a reactance from our shack?\n \n Th e Smith Chart - we have to spend more time on this graph\n The POLAR graph has some real benefits over a rectilinear X,Y graph.\n \n Resonance again -  is it always the "lowest SWR" point?  \n Don't confuse resonance (no reac tance) with the best match.\n My  130 ft  long 80m dipole 25 ft above groun d has a much lower impedance than 50 ohms so without a matching coil I get a fairly large SWR on  50 ohm coax.  Now what?\n \n Bring quesions and comm ents to this Zoom talk.\n \n12thJuly 2021 19.30 BST 18.30 UTC\n\nJoin Zoom Meeting\nhttps://us02web.zoom.us/j/9149763075?pwd=WEJicFc4U0FVNUc1MUJ6WVB3W lNQdz09\nMeeting ID: 914 976 3075\nPasscode: 0eGTG0\nOne tap mobile\n+44131 4601196,,9149763075#,,,,*442838# United Kingdom\n+442030512874,,9149763075# ,,,,*442838# United Kingdom\nDial by your location\n        +44 131 460 119 6 United Kingdom\n        +44 203 051 2874 United Kingdom\n        +44 203 481 5237 United Kingdom\n        +44 203 481 5240 United Kingdom\n        + 44 203 901 7895 United Kingdom\nMeeting ID: 914 976 3075\nPasscode: 442838\ n X-ALT-DESC;FMTTYPE=text/html:

LRS Online Club Night Topic: NanoVNA: An Ante nna Stethoscope Part 2

Please join me tonight to take another look at the Nano VNA.
What exactly does it measure?  What is ca lculated?

Are we able to interpret what each of the following graphs are showing about an antenna's performance?

Reflection Coefficient (magnitude)
Return Loss (dB)
SWR

Quest ion:
Which impedance has the largest SWR value with  50 ohm coax feed line:
    25+jo,  100+j0,  40+j30,  40 -j30

What level of attenuation (dB) in our feed line is "accep table" ?

Then Resistance, Reactance, and Impedance:  what do these mean?
When operating off the resonant frequency, which chan ges faster: resistance or reactance?

How can we correct a reac tance (at the antenna)?
How can we correct a reactance from our shack ?

The Smith Chart - we have to spend more time on this graph The POLAR graph has some real benefits over a rectilinear X,Y graph.
Resonance again -  is it always the "lowest SWR" point? &n bsp;
Don't confuse resonance (no reactance) with the best match.
My  130 ft  long 80m dipole 25 ft above ground has a much lower impedance than 50 ohms so without a matching coil I get a fairly large SWR on  50 ohm coax.  Now what?

Bring quesions and comm ents to this Zoom talk.

 

12thJuly 2021 19.30 BST 18.30 UTC

Join Zoom Meeting
https://us02web.zoom.us/j/9149763075?pwd=WEJ icFc4U0FVNUc1MUJ6WVB3WlNQdz09

Meeting ID: 914 976 3075
Passcode: 0eGTG0
One tap mobile
+441 314601196,,9149763075#,,,,*442838# United Kingdom
+442030512874,,9149763075#,,,,*442838# United Kingdo m

Dial by your location
        +44 13 1 460 1196 United Kingdom
& nbsp;       +44 203 051 2874 United Kingdom
    &nbs p;   +44 203 481 5237 United Kingdom
        +44 203 481 5240 United Kingdom
 & nbsp;      +44 203 901 7895 United Kingdom
Meeting ID: 914 976 3075
Passcode: 442838

CONTACT:Dave G8PGO DTSTAMP:20260415T014745 DTSTART;TZID=Europe/London:20210712T193000 DTEND;TZID=Europe/London:20210712T220000 SEQUENCE:0 TRANSP:OPAQUE END:VEVENT END:VCALENDAR