Date   

NanoVNA Basics #howto

Jon - KI6RT
 

Attached is a very Basic NanoVNA how to...

Jon KI6RT


SFARC General Meeting - Fri, 04/09/2021 7:30pm-9:30pm #cal-reminder

sfarc@w6ek.groups.io Calendar <sfarc@...>
 

Reminder: SFARC General Meeting

When: Friday, 9 April 2021, 7:30pm to 9:30pm, (GMT-07:00) America/Los Angeles

Where:ONLINE

View Event

Description:

Join us for the SFARC Online Club Meeting from your computer, tablet, smartphone or even by regular telephone. You do not need to be a member and everyone is invited to attend!

Meeting Log-in Information

https://zoom.us/j/96261675605

Meeting ID: 962 6167 5605

You may instead call in using only your telephone.

1-669-900-9128, 96261675605#

Teleconference etiquette is to mute your own microphone unless you are speaking. Please join the teleconference from a quiet location, without background noise as this can be very disruptive to other participants. Sign in using your first name and call sign as ID.


Upcoming repeater usage for April and Coffee Break Net.

Clyde Campbell
 

The W6EK 2 & 440 repeater has been reserved to support the following events for April 2021:
17 April American River Classic Endurance Ride 0600-1500 hours
24 April Canyons 100K Run   0500- until
In support of these events there will be no Coffee Break Net on those days, also the 440 repeater will be in analog mode and linked to the 2 meter machine.
Also coming up in May are practice runs for the Western States  100 mile Run. The Run will be Held June 26-26 so there will be now Coffee Break of Field Day nets on those days.
The Tevis Cup will also run in July on the 24th.
Details on all events will be posted closer to the dates. If you are interested in volunteering for any of these or other events see the clubs web page at W6EK.org
Clyde Campbell AB4CC
Station Trustee W6EK


End of PiGate

Ken - K6KEC
 

Sharing the below announcement regarding PiGate ...  If you are a PiGate user you might want to download the images and documentation before it disappears...

 

Email about PiGate 

Dear Friends and PiGate Supporters,

It is with a sad heart that I must announce the ending of all PiGate  operations.  During the past few years as I enjoyed my retirement, it  has become increasingly hard to pay the expenses of keeping the PiGate  website operational, as well as the FTP download site.  As a result of  increasing costs, on Monday, April 12th, the website www.pigate.net will be taken down, the domain name deactivated, and the FTP site will also end service.

I have spent the majority of my adult life working with computer systems  of all kinds, writing code in several different languages, helping  people better use their computing resources, and I will miss all of  this.  If anyone needs help with a PiGate system in the future, please  don't hesitate to ask at my personal email address given below.  I'll  keep my development system up and running for at least the next year  just in case I need to consult it for some reason.

Thanks again for being such a friendly group of people!

Mark Griffith
KD0QYN

 


SFARC Net - Thu, 04/08/2021 #cal-notice

sfarc@w6ek.groups.io Calendar <noreply@...>
 

SFARC Net

When:
Thursday, 8 April 2021
7:30pm to 8:30pm
(GMT-07:00) America/Los Angeles

Where:
W6EK Repeater - 145.430 -600, PL162.2

Description:
Check-in for Club updates from Officers and members, QSTs and more. Everyone is welcome!


SFARC Board Meeting - Fri, 04/09/2021 6:00pm-7:00pm #cal-reminder

sfarc@w6ek.groups.io Calendar <sfarc@...>
 

Reminder: SFARC Board Meeting

When: Friday, 9 April 2021, 6:00pm to 7:00pm, (GMT-07:00) America/Los Angeles

Where:ONLINE

View Event

Description: Monthly SFARC Board meeting will be held ONLINE until further notice. Join our meeting from your computer, tablet or smartphone. 

Meeting ID: 962 6167 5605

You can also call in using only your telephone.

1-669-900-9128, 96261675605#

 


Next Field Day Meeting - Apr 12 at 7 pm

Gerry - WA6E
 

Greetings fellow members -

It's time for another Field Day meeting.  It will be this coming Monday, April 12, at 7 pm via zoom meeting.  Details below. 

Whether or not you are part of the committee please feel free to join us.

At the moment we are planning on operating at the Blue Canyon Airport as we did in 2019.  The Forest Service is not approving use applications yet because they don't have direction from higher HQ on approving such applications given the covid pandemic.  We submitted our application anyway in the hope that we will get approval before June.  Otherwise we do have a backup.

Looking forward to your joining us at the meeting.

73,

Gerry

WA6E


Join our meeting from your computer, tablet or smartphone. 

Meeting ID: 962 6167 5605

You can also call in using only your telephone.

1-669-900-9128, 96261675605#


Re: 5/8th Wave Antennas Why does the 5/8th have gain, and how much gain does it have?

Greg - KO6TH
 

Good info, Jef.  I am running a 5/8 wave J-pole for my packet station, and it works pretty well.

A follow-up to the satellite question..  One generally wants some sort of gain, such as a small beam.  Satellites are relatively weak, since they're hundreds to thousands of miles a way (line of sight), and generally don't have much by way of transmit power.  The exception is the International Space Station, which is in a fairly low orbit, and has a transmitter with some oomph behind it (up to 25 w, but they probably run at a bit lower power).  SO-50 is one of the weaker ones at 250mw, and many of the "cubesats" aren't running much more.

All that said, one of the better antennas can be a simple 2m 1/4 wave ground plane antenna, operated in dual-band mode.  On it's 3rd harmonic fro 70cm, it turns out to have some gain upwards from the horizontal, which helps with satellite work.  It's still not wonderful, but a LOT better than an HT's antenna, and can sometimes be better than a high gain omni antenna, where the pattern is aimed at the horizon. 

http://aprs.org/aprs-satellite-igate-antennas.html  (Old satellite and product info, but physics still works.)

Greg  KO6TH


Jef - N5JEF wrote:

Tonight someone on the Elmer net was asking about ⅝λ antennas with regard to a ground plane.  I tried to explain that a ⅝λ antenna is already a complete antenna, so it doesn't require a ground to make it complete the way a ¼λ wave antenna does.  Further, a ⅝λ antenna gets its gain (lower-angle radiation) from ground reflections further out from its base.

Here's a page that I think explains ⅝λ antennas very well and clears up some myths and folklore:  https://www.w8ji.com/VHF%20mobile%20vertical.htm

As a related matter, it seems that few people realize that a ¼λ whip with a decent ground plane has 3dB gain over a full-length vertical dipole twice its length.

- Jef N5JEF


5/8th Wave Antennas Why does the 5/8th have gain, and how much gain does it have?

Jef - N5JEF
 

Tonight someone on the Elmer net was asking about ⅝λ antennas with regard to a ground plane.  I tried to explain that a ⅝λ antenna is already a complete antenna, so it doesn't require a ground to make it complete the way a ¼λ wave antenna does.  Further, a ⅝λ antenna gets its gain (lower-angle radiation) from ground reflections further out from its base.

Here's a page that I think explains ⅝λ antennas very well and clears up some myths and folklore:  https://www.w8ji.com/VHF%20mobile%20vertical.htm

As a related matter, it seems that few people realize that a ¼λ whip with a decent ground plane has 3dB gain over a full-length vertical dipole twice its length.

- Jef N5JEF


Re: Radio humor #repair

Devon, KM6MDG
 

So it must release "magic smoke" then. ;)


Elmer Net - Wed, 04/07/2021 7:30pm-8:30pm #cal-reminder

sfarc@w6ek.groups.io Calendar <sfarc@...>
 

Reminder: Elmer Net

When: Wednesday, 7 April 2021, 7:30pm to 8:30pm, (GMT-07:00) America/Los Angeles

Where:W6EK Repeater - 145.430 -600, PL162.2

View Event

Description:

The Elmer Net meets every 1st and 3rd Wednesday, and is devoted to answering your questions, solving puzzling issues related to ham radio, and scheduling help for all Hams. No question is "stupid". We encourage everyone to ask away so we can all learn and grow our knowledge together. Web address: http://w6ek.org/nets.html


SFARC Net - Thu, 04/08/2021 7:30pm-8:30pm #cal-reminder

sfarc@w6ek.groups.io Calendar <sfarc@...>
 

Reminder: SFARC Net

When: Thursday, 8 April 2021, 7:30pm to 8:30pm, (GMT-07:00) America/Los Angeles

Where:W6EK Repeater - 145.430 -600, PL162.2

View Event

Description: Check-in for Club updates from Officers and members, QSTs and more. Everyone is welcome!


Re: RDF Base Station Antenna prototype

Jon - KI6RT
 

For EEs that have run out of things to read...
https://w6ek.groups.io/g/sfarc/files/RDF%20Project%20Files/base%20station%20electronics.pdf

Any inputs/refinements to the RDF electronics? 
  • I usually put a Nano footprint on the board so that a Nano can just be plugged in. Should it be shield instead?
  • I used a 555 as a DC/DC voltage inverter to generate -12V. Why not an LDO? Cost. The 555 circuit is cheaper.
  • Not sure a LP filter is needed. I wanted some type of buffer for the audio therefore rather than a unity gain buffer decided might as well make it a Sallen-Key LP with an Fc of around 700 Hz.
  • Integrator to shape antenna pulses -- with the slow rise time there should be no need for a PIN diode. Thoughts?
  • Have made no attempts to separate ground domains (rf, digital, analog). Should we separate ground domains and place mecca ground at the DC input? I think not critical but...
Anyone have their CNC setup to route PCBs? I damaged stepper motor on mine so need to fix. If you have such a capability let me know & I'll send over the Geber and PCB blank.

Thanks in advance for your inputs.

Jon


Radio humor #repair

KM6YKX - Rob Newburn
 
Edited

Some people may have created this scent without the candle...

Cheers/73!
Rob - KM6YKX


RDF Base Station Antenna prototype

Jon - KI6RT
 

RDF Base Station Antenna prototype for discussion. 
The proto shown is not using final PCBs (out for fabrication). Whips shown using copper wire (pulled off of scrap Romex) not stainless steel nor telescopic elements. But it solved the primary problem -- eliminates hassle of setting up the antenna to test/evaluate the RDF Doppler electronics.  

Link to full document below. Comments welcome.
https://w6ek.groups.io/g/sfarc/files/RDF%20Project%20Files/base%20station%20antenna.pdf


Re: FOR SALE: Ameritron AL-811H 800W linear, MFJ-989D1200W tuner, MFJ-929 200W tuner, AA-55 Zoom #forsale

Brian - AI6US
 

Bump...
--
Brian- AI6US


Re: Turboencabulator history and success revisited

Jef - N5JEF
 

Reminds me of this classic (I have a printed copy on my SCADA test stand):

image.png
- Jef  N5JEF


Turboencabulator history and success revisited

Jim - N6MED
 

I'm guessing most everyone has not only heard the story but seen the GMC training film re the Turbo Encabulator.

Enjoy this article that revisits it and more:

https://www.avclub.com/the-turboencabulator-was-the-most-complicated-device-ne-1846599079

The link in the article to the GM 1977 training film:

https://www.youtube.com/watch?v=Ac7G7xOG2Ag

Chrysler improved on the design and service in 1988:

https://www.youtube.com/watch?v=MXW0bx_Ooq4


Re: Starlink Satellite Launch Tomorrow #QST #satellites

Greg - KO6TH
 

Thanks, Dennis.

But, 5:30am?

{sigh}

Greg  KO6TH


Dennis - WU6X wrote:

60+ satellites going up tomorrow ... Click the link to see more info:

https://james.darpinian.com/satellites/?special=starlink

Heavens Above is also a good site: https://www.heavens-above.com/main.aspx?Session=kebgfcjhhcidfomaleeflaka

73, Dennis - WU6X


Re: FOR SALE: Uniden BCD436HP Digital Handheld Scanner #forsale

Alan - W6WN
 

Just a note: This scanner supports "Fire Tone Out" functionality, which enables it to remain silent until it detects a transmission from one or more fire stations that are geographically local to your neighborhood. This is a critical feature in fire country that all scanners should have - but many don't.

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