Date   
Loomis Hamfest Planning Meeting Reminder

Orion, AI6JB
 

Good Evening Everyone!

Quick reminder, we are having our last Hamfest Planning meeting at the site tomorrow evening starting at 5:00 PM.  All team leads and members are invited to attend.  We'll be finalizing logistics and layout.  Hope to see you all there.

The Loomis Hamfest site is located at 5775 Horseshoe Bar Road in downtown Loomis.  We will meet at the train depot building.

73
Orion, AI6JB
2020 Loomis Hamfest Chair

Re: W6EK 2M Repeater Failure Update

Clyde Campbell
 

While not a ham radio system this is an example of how far we have progressed. When I went to work CALOES in 1978 we had a  Statewide single pair VHF radio system that employed two PL tones one for state use and one for counties to use. The mountain top repeaters were controlled by a burst tone. To further complicated matters the repeaters were microwave interconnect. So the early mobile had an outboard Burst tone box and rotary dial to activate the microwave system. The rotary dial was later replaced by an outboard DTMF box. 
73 de AB4CC Clyde

Re: W6EK 2M Repeater Failure Update

Casey - W7IB
 

I still have the IC-AT with the dip switches and it still works well!

On Sun, Mar 8, 2020 at 4:03 PM Orion, AI6JB <ojendres@...> wrote:

Skip,

 

Thank you for the historical perspective!  As a relatively new ham, PLs are SOP and are easily programmed on our radios. 

 

73

Orion Endres, AI6JB

1201 Wood Oak Court, Roseville, CA 95747-7383

(916) 788-8251 H \\ (916) 534-8251 C

 

What the heck does “73” mean?  73 is morse code short hand for “Best Regards” used by Ham radio operators.  It’s origin goes all the way back to the landline telegraph days.

 

 

 

From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> On Behalf Of Dennis - WU6X
Sent: Sunday, March 08, 2020 14:14
To: sfarc@w6ek.groups.io; k6dgw@...
Subject: Re: [from W6EK Groups.io] W6EK 2M Repeater Failure Update

 

Hey, I "resemble" those days, Skip. Hi! I had an IC-2AT into which I installed the ComSpec PL board with the DIP switches exposed out the rear ... it worked great! Getting the level "right" was always a challenge in those early years, adjusting so it didn't get passed through with the audio, so loud that people complained you had a power supply hummmmm!

 

Tnx for the memories!

 

Dennis, WU6X

 


From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> on behalf of Skip - K6DGW <k6dgw@...>
Sent: Sunday, March 8, 2020 12:02 PM
To: Greg D <ko6th.greg@...>; sfarc@w6ek.groups.io <sfarc@w6ek.groups.io>
Subject: Re: [from W6EK Groups.io] W6EK 2M Repeater Failure Update

 

K6ARR was originally on 146.16/.76 and the PL was missing.  While popular in congested areas such as SoCal and Silicon Valley, PL didn't make it to the "rural" repeaters until about 1980.  There was some co-channel QRM from a system in the San Joaquin Valley and eventually, Jim put 94.8 PL on the .16/.76 repeater.  This was a moderately big deal for most users at the time because few of the HT's and mobiles in use had PL built it and you had to get a ComSpec PL board and wire it into your radio(s).  The move to 144.83/145.43 took place shortly after the FCC opened that sub-band for repeaters.  The PL was 162.2 and it still is, or was last time I was in Auburn a few weeks ago.  .16/.76 was the second most popular repeater pair in the country after .34/.94 and many re-purposed land mobile radios had crystals for those two channels only.

Being the Poster Boy for "Old," I couldn't remember some of the details but fortunately, I found them in one of my old station notebooks.

73,

Fred ["Skip"] K6DGW
Really Old Guy in Sparks NV



--
Dennis - WU6X

--
73 de W7IB Casey

How Rockets are Made #QST

Dennis - WU6X
 

This video takes you through the United Launch Alliance (ULA) rocket factory in Decatur, AL just down the street from the US Space & Rocket Center in Huntsville, AL. If you've been to the US Space & Rocket Center (I've been twice) to see the finished product, or you are an engineer, you will thoroughly enjoy this video tour by CEO Tory Bruno, a real "rocket scientist" turned executive. It's a long video, but well worth it. The Decatur factory designs and builds the Atlas V, Delta IV, and the new Vulcan Centaur rocket. Unbelievable technical and engineering expertise!

https://www.youtube.com/watch?v=o0fG_lnVhHw

Enjoy,
Dennis - WU6X

Call for Volunteers - CERA Enduro - Sunday, May 3

Michael - N6MRP
 

The California Endurance Riders Association's Fool's Gold Enduro is less than two months away! (Sunday, May 3)

SFARC has supported the CERA enduros with communications support for many years. This is a great event to use 2 meter mobile gear in a field environment. Operators new to the hobby are especially welcome - you'll get plenty of air time! We operate in Eldorado National Forest east of Georgetown, with Net Control at the Start/Finish and field stations around the course. 

Please let me know if you're interested in volunteering!

73

Mike Perry N6MRP
SFARC Volunteer Events Coordinator


Re: W6EK 2M Repeater Failure Update

Orion, AI6JB
 

Skip,

 

Thank you for the historical perspective!  As a relatively new ham, PLs are SOP and are easily programmed on our radios. 

 

73

Orion Endres, AI6JB

1201 Wood Oak Court, Roseville, CA 95747-7383

(916) 788-8251 H \\ (916) 534-8251 C

 

What the heck does “73” mean?  73 is morse code short hand for “Best Regards” used by Ham radio operators.  It’s origin goes all the way back to the landline telegraph days.

 

 

 

From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> On Behalf Of Dennis - WU6X
Sent: Sunday, March 08, 2020 14:14
To: sfarc@w6ek.groups.io; k6dgw@...
Subject: Re: [from W6EK Groups.io] W6EK 2M Repeater Failure Update

 

Hey, I "resemble" those days, Skip. Hi! I had an IC-2AT into which I installed the ComSpec PL board with the DIP switches exposed out the rear ... it worked great! Getting the level "right" was always a challenge in those early years, adjusting so it didn't get passed through with the audio, so loud that people complained you had a power supply hummmmm!

 

Tnx for the memories!

 

Dennis, WU6X

 


From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> on behalf of Skip - K6DGW <k6dgw@...>
Sent: Sunday, March 8, 2020 12:02 PM
To: Greg D <ko6th.greg@...>; sfarc@w6ek.groups.io <sfarc@w6ek.groups.io>
Subject: Re: [from W6EK Groups.io] W6EK 2M Repeater Failure Update

 

K6ARR was originally on 146.16/.76 and the PL was missing.  While popular in congested areas such as SoCal and Silicon Valley, PL didn't make it to the "rural" repeaters until about 1980.  There was some co-channel QRM from a system in the San Joaquin Valley and eventually, Jim put 94.8 PL on the .16/.76 repeater.  This was a moderately big deal for most users at the time because few of the HT's and mobiles in use had PL built it and you had to get a ComSpec PL board and wire it into your radio(s).  The move to 144.83/145.43 took place shortly after the FCC opened that sub-band for repeaters.  The PL was 162.2 and it still is, or was last time I was in Auburn a few weeks ago.  .16/.76 was the second most popular repeater pair in the country after .34/.94 and many re-purposed land mobile radios had crystals for those two channels only.

Being the Poster Boy for "Old," I couldn't remember some of the details but fortunately, I found them in one of my old station notebooks.

73,

Fred ["Skip"] K6DGW
Really Old Guy in Sparks NV



--
Dennis - WU6X

Re: W6EK 2M Repeater Failure Update

Dennis - WU6X
 

Hey, I "resemble" those days, Skip. Hi! I had an IC-2AT into which I installed the ComSpec PL board with the DIP switches exposed out the rear ... it worked great! Getting the level "right" was always a challenge in those early years, adjusting so it didn't get passed through with the audio, so loud that people complained you had a power supply hummmmm!

Tnx for the memories!

Dennis, WU6X


From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> on behalf of Skip - K6DGW <k6dgw@...>
Sent: Sunday, March 8, 2020 12:02 PM
To: Greg D <ko6th.greg@...>; sfarc@w6ek.groups.io <sfarc@w6ek.groups.io>
Subject: Re: [from W6EK Groups.io] W6EK 2M Repeater Failure Update
 
K6ARR was originally on 146.16/.76 and the PL was missing.  While popular in congested areas such as SoCal and Silicon Valley, PL didn't make it to the "rural" repeaters until about 1980.  There was some co-channel QRM from a system in the San Joaquin Valley and eventually, Jim put 94.8 PL on the .16/.76 repeater.  This was a moderately big deal for most users at the time because few of the HT's and mobiles in use had PL built it and you had to get a ComSpec PL board and wire it into your radio(s).  The move to 144.83/145.43 took place shortly after the FCC opened that sub-band for repeaters.  The PL was 162.2 and it still is, or was last time I was in Auburn a few weeks ago.  .16/.76 was the second most popular repeater pair in the country after .34/.94 and many re-purposed land mobile radios had crystals for those two channels only.

Being the Poster Boy for "Old," I couldn't remember some of the details but fortunately, I found them in one of my old station notebooks.

73,

Fred ["Skip"] K6DGW
Really Old Guy in Sparks NV




--
Dennis - WU6X

Re: W6EK 2M Repeater Failure Update

Skip - K6DGW
 

K6ARR was originally on 146.16/.76 and the PL was missing. While popular in congested areas such as SoCal and Silicon Valley, PL didn't make it to the "rural" repeaters until about 1980. There was some co-channel QRM from a system in the San Joaquin Valley and eventually, Jim put 94.8 PL on the .16/.76 repeater. This was a moderately big deal for most users at the time because few of the HT's and mobiles in use had PL built it and you had to get a ComSpec PL board and wire it into your radio(s). The move to 144.83/145.43 took place shortly after the FCC opened that sub-band for repeaters. The PL was 162.2 and it still is, or was last time I was in Auburn a few weeks ago. .16/.76 was the second most popular repeater pair in the country after .34/.94 and many re-purposed land mobile radios had crystals for those two channels only.

Being the Poster Boy for "Old," I couldn't remember some of the details but fortunately, I found them in one of my old station notebooks.

73,

Fred ["Skip"] K6DGW
Really Old Guy in Sparks NV

Re: W6EK 2M Repeater Failure Update

Greg D
 

It's always been on 145.430 for me, but if I recall, the PL was 94.8.  That would have been back in the early 1990's... 

"Old" has been official since my birthday a few months ago.  As for the memory, well, that's the second thing to go...

Greg  KO6TH


Skip - K6DGW wrote:

Repeater Trivia Question:

What frequency pair was the original SFARC [K6ARR] repeater on and what was the PL?  You are officially old but have a good memory if you know this.

73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 3/7/2020 3:56 PM, AI6US wrote:

Hello SFARC Members,

The 2 meter repeater is the heart beat of the SFARC. It is a great resource to stay in touch with friends, check into the nets (if only to answer the mystery question), supports our community with event communications, encourages learning and sharing on the Elmer Net, sharpens our communications skills, prepares us for an emergency response with ARES nets / exercises or simply a fun place to rag chew as we sip our morning coffee. I didn't really think about how I would miss the W6EK 2 meter repeater.... until we could barely copy the signal this past week.

Just wanted to provide an update on the W6EK 2 meter repeater, which had been having intermittent signal breaks during the past few weeks and failed this past Wednesday. The PA was only outputting 1/2 watt instead of the usual 45w. On Thursday, Clyde, AB4CC; Marv, N7MSM; Ken, KA6SUB and I met at the vault. The 70cm repeater programming was enhanced with on-demand linking to Gold Run, Bakersfield and other repeater systems. We swapped out to the spare 2 meter transmitter, but it also had a defect and only transmitted noise.

Bob - K6UDA graciously loaned the club a Yaesu DR-1X repeater and with the assistance of Jeff, AK6OK, we successfully restored the W6EK 2 meter repeater operations with limited coverage and services on Friday afternoon. The repeater is operating at a reduced power level of 20w. Until the situation is resolved, you may experience a reduced reception range from the repeater. Without a controller interface adapter, the repeater operation is limited to local repeater communications and the extra features such as phone patch, voice playback, DTMF testing, AllStarLink, Echolink and the Broadcastify internet feed will not be available.

Kerchunk, Kerchunk, Kerchunk... Yes, the squelch tail is currently very short and the carrier drops without a roger beep. Many kerchunkers might think that they are not hitting the repeater, but it is working! Please throw out your call! Someone is likely to be listening and respond. :)


Last evening, an emergency SFARC repeater meeting met and we reviewed the incident, repair and replacement options. In attendance were SFARC club members: Orion, AI6JB; Greg, KO6TH; Brian, AI6US; Marv, N7MSM; Clyde, AB4CC; Jim, WA8MPA; Bob, K6UDA; Gerry, WA6E. It is estimated that the SFARC repeaters have been in service between 25 to 35 years and have recently been experiencing reliability issues. The event communication support season begins soon and the first WSER training run is less than two months away. We must have the system fully operational and tested in perparation for these upcoming events. The repeater committee unanimously recommends an equipment purchase for the SFARC Board and Membership consideration and approval. The repeater account has funding for this purchase and a healthy reserve would remain for tower, antenna and feedline replacement or if required, a site relocation.

The repeater committee equipment recommendations total under $3000 and include these items:
2x - Yaesu DR-2X with LAN, one unit designated for daily operations and the second for back-up.  $900 each after the Yaesu Club Repeater Discount
1x - Henry 100w+ amplifier - Approx $600
1x - Arcom Controller interface - Donation from Ken, KA6SUB
1x - Arcom Controller interface - Donation from Jeff, AK6OK

The March 6, 2020 emergency repeater meeting notes are posted in the repeater documents section on the SFARC Groups.io site or if you have not joined this group, I will email a copy upon request. Please review the repeater committee recommendations and contact any of the members or board members ASAP with any questions or comments. The board and SFARC members will vote on this recommendation next Friday, March 13, 2020 at the monthly SFARC board and Club meetings. The board meeting starts at 6pm at Mel's Diner in Auburn and followed by the general club meeting at 7:30pm in the Rose Room at the Auburn City Hall.

Thank you for your continued support of SFARC. Looking forward to seeing you next Friday.

Catch you on the repeater or give me a call. 73

Brian Gohl
SFARC President
916-770-7751 cell


Re: W6EK 2M Repeater Failure Update

Skip - K6DGW
 

Repeater Trivia Question:

What frequency pair was the original SFARC [K6ARR] repeater on and what was the PL?  You are officially old but have a good memory if you know this.

73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 3/7/2020 3:56 PM, AI6US wrote:

Hello SFARC Members,

The 2 meter repeater is the heart beat of the SFARC. It is a great resource to stay in touch with friends, check into the nets (if only to answer the mystery question), supports our community with event communications, encourages learning and sharing on the Elmer Net, sharpens our communications skills, prepares us for an emergency response with ARES nets / exercises or simply a fun place to rag chew as we sip our morning coffee. I didn't really think about how I would miss the W6EK 2 meter repeater.... until we could barely copy the signal this past week.

Just wanted to provide an update on the W6EK 2 meter repeater, which had been having intermittent signal breaks during the past few weeks and failed this past Wednesday. The PA was only outputting 1/2 watt instead of the usual 45w. On Thursday, Clyde, AB4CC; Marv, N7MSM; Ken, KA6SUB and I met at the vault. The 70cm repeater programming was enhanced with on-demand linking to Gold Run, Bakersfield and other repeater systems. We swapped out to the spare 2 meter transmitter, but it also had a defect and only transmitted noise.

Bob - K6UDA graciously loaned the club a Yaesu DR-1X repeater and with the assistance of Jeff, AK6OK, we successfully restored the W6EK 2 meter repeater operations with limited coverage and services on Friday afternoon. The repeater is operating at a reduced power level of 20w. Until the situation is resolved, you may experience a reduced reception range from the repeater. Without a controller interface adapter, the repeater operation is limited to local repeater communications and the extra features such as phone patch, voice playback, DTMF testing, AllStarLink, Echolink and the Broadcastify internet feed will not be available.

Kerchunk, Kerchunk, Kerchunk... Yes, the squelch tail is currently very short and the carrier drops without a roger beep. Many kerchunkers might think that they are not hitting the repeater, but it is working! Please throw out your call! Someone is likely to be listening and respond. :)


Last evening, an emergency SFARC repeater meeting met and we reviewed the incident, repair and replacement options. In attendance were SFARC club members: Orion, AI6JB; Greg, KO6TH; Brian, AI6US; Marv, N7MSM; Clyde, AB4CC; Jim, WA8MPA; Bob, K6UDA; Gerry, WA6E. It is estimated that the SFARC repeaters have been in service between 25 to 35 years and have recently been experiencing reliability issues. The event communication support season begins soon and the first WSER training run is less than two months away. We must have the system fully operational and tested in perparation for these upcoming events. The repeater committee unanimously recommends an equipment purchase for the SFARC Board and Membership consideration and approval. The repeater account has funding for this purchase and a healthy reserve would remain for tower, antenna and feedline replacement or if required, a site relocation.

The repeater committee equipment recommendations total under $3000 and include these items:
2x - Yaesu DR-2X with LAN, one unit designated for daily operations and the second for back-up.  $900 each after the Yaesu Club Repeater Discount
1x - Henry 100w+ amplifier - Approx $600
1x - Arcom Controller interface - Donation from Ken, KA6SUB
1x - Arcom Controller interface - Donation from Jeff, AK6OK

The March 6, 2020 emergency repeater meeting notes are posted in the repeater documents section on the SFARC Groups.io site or if you have not joined this group, I will email a copy upon request. Please review the repeater committee recommendations and contact any of the members or board members ASAP with any questions or comments. The board and SFARC members will vote on this recommendation next Friday, March 13, 2020 at the monthly SFARC board and Club meetings. The board meeting starts at 6pm at Mel's Diner in Auburn and followed by the general club meeting at 7:30pm in the Rose Room at the Auburn City Hall.

Thank you for your continued support of SFARC. Looking forward to seeing you next Friday.

Catch you on the repeater or give me a call. 73

Brian Gohl
SFARC President
916-770-7751 cell

SFARC Net - Thu, 03/05/2020 #cal-notice

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

SFARC Net

When:
Thursday, 5 March 2020
7:30pm to 8:30pm
(GMT-08:00) 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!

Upcoming Event: VE Exams Session #ve - Sat, 03/07/2020 8:00am-9:00am #ve #cal-reminder

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

Reminder: VE Exams Session #ve

When: Saturday, 7 March 2020, 8:00am to 9:00am, (GMT-08:00) America/Los Angeles

Where:Raley's Granite Bay

View Event

Organizer: Al Martin - NI2U

Description: ARRL VE testing for all license classes, walk-ins welcomed! Please get there early. Sessions start at 8am. See http://w6ek.org/FCCexams.html for details and map.

One-Day Ham Radio Class, May 2 #elmer

Dennis - WU6X
 

Once again the Benicia Amateur Radio Club and its volunteers will be conducting another One-Day Ham Radio Class. This class is intended for those wishing to get a Tech Ham license, or existing Techs wishing to upgrade to General.

Conducted multiple times throughout the year, this class has been very well received by the greater Northern California community. We have helped Hams from Shasta to Santa Cruz, the San Joaquin Valley, and from the Peninsula to the Sierra Foothills.

Many of us know people that we’d love to see get into our exciting hobby but have faced opposition because they didn’t have time to study. As we know, many people typically require one to two months to prepare to pass their test.

We have the answer. Earn a license or upgrade in One Day!

Historically over 90% of attendees pass the on-site FCC licensing exam. Our exams are administered by federally accredited Volunteer Examiners (VEs) immediately at the conclusion of the class. Our proven class pass rate easily exceeds home study results.

We’re seeing our successful attendees now volunteering for On-The-Air activities, Drills, Nets & Public Service Events, and accepting leadership roles on club boards and committees.

We invite all persons interested in obtaining a Ham license - or Techs wishing to upgrade - to enroll in this One-Day class. We have over 30 Facilitators and Accredited VEs to help deliver this successful class.

 

When:              May 2, 2020,  7:30 AM - 5:00 PM

Where:           Benicia Senior Center, 1201 East 2nd Street, Benicia, CA 94510 (map)

Cost:              $35. Includes all study material, venue, day-long refreshments, handouts, freebies and the federally required exam fee. All instructors, facilitators and VEs are volunteers.

Access:         Our facility has full handicap access.

Info/Signup: Online at www.BeniciaARC.com. Class size is limited and it always fills up, so register promptly.

Questions:   hamradioclass@... or class coordinator Bob Fentress (707) 742-3227

Class Flyer attached.

Re: NVIS Propagation #antennas #elmer #emcomm

Jef - N5JEF
 

I should probably mention also that the inverted V configuration for NVIS is very easy, but not ideal because it can pick up significantly more noise from (1) moderate distance lightning storms, and (2) the vertically polarized electrical noise from nearby civilization via ground-wave propagation. So a flat top dipole (even dipping slightly in the middle) is better than an inverted V for best regional communications out to about 300 miles.

- Jef  N5JEF

On Wed, Mar 4, 2020 at 9:57 AM Jef - N5JEF via Groups.Io <jef=jefallbright.net@groups.io> wrote:
That's a handy way to set up for NVIS in the field with only a single (central) support.

The important thing is to get the center up at least 1/8 wavelength above the ground for efficient NVIS--so at least 15 feet for 40 meters and about 25-30 feet up for 75 meters (and the 25-30 feet height will work very well for both 40 and 75 meters NVIS).

Keep in mind that the inner third of the antenna carries the bulk of the current, so you want to have _that portion_ roughly up to an effective height.  It matters very little what you do with the ends or whether they're straight or not.

That said, the ends of the antenna are very low (displacement) current, but can be quite high voltage depending on the operating power, and that voltage field at each end can and will interact with the earth manifesting SWR instability, so try to keep the ends up at least 4 or five feet above the ground if possible. 

Just for reference, a classic inverted V with the ends each coming down at 45 degrees will be a worse than 3dB down compared to a flat top dipole (for NVIS), but will slightly improve operation in the moderate distance range beyond 300 miles but closer than proper skip range.

FYI,

- Jef  N5JEF 

On Wed, Mar 4, 2020 at 9:17 AM Rob Newburn <robnewburn@...> wrote:
I cant remember what it was called but an inverted v with the ends close to the ground worked real good for near to medium.


Re: NVIS Propagation #antennas #elmer #emcomm

Jef - N5JEF
 

That's a handy way to set up for NVIS in the field with only a single (central) support.

The important thing is to get the center up at least 1/8 wavelength above the ground for efficient NVIS--so at least 15 feet for 40 meters and about 25-30 feet up for 75 meters (and the 25-30 feet height will work very well for both 40 and 75 meters NVIS).

Keep in mind that the inner third of the antenna carries the bulk of the current, so you want to have _that portion_ roughly up to an effective height.  It matters very little what you do with the ends or whether they're straight or not.

That said, the ends of the antenna are very low (displacement) current, but can be quite high voltage depending on the operating power, and that voltage field at each end can and will interact with the earth manifesting SWR instability, so try to keep the ends up at least 4 or five feet above the ground if possible. 

Just for reference, a classic inverted V with the ends each coming down at 45 degrees will be a worse than 3dB down compared to a flat top dipole (for NVIS), but will slightly improve operation in the moderate distance range beyond 300 miles but closer than proper skip range.

FYI,

- Jef  N5JEF 

On Wed, Mar 4, 2020 at 9:17 AM Rob Newburn <robnewburn@...> wrote:
I cant remember what it was called but an inverted v with the ends close to the ground worked real good for near to medium.


Re: NVIS Propagation #antennas #elmer #emcomm

Rob Newburn
 

I cant remember what it was called but an inverted v with the ends close to the ground worked real good for near to medium.

Here is a cool link:

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.marines.mil/Portals/1/Publications/MCRP%25208-10B.11.pdf%3Fver%3D2017-03-15-092827-423&ved=2ahUKEwjwm96hqIHoAhWMIjQIHUXyDuIQFjAAegQIAxAC&usg=AOvVaw210cZWsi4TvsrE_u_AmYCV

Rob



Re: NVIS Propagation #antennas #elmer #emcomm

Brian Gohl - AI6US
 

Has this NVIS presentation been made for a SFARC meeting? Maybe before my time in the club? If not, please contact Greg, KO6TH and putvitvin the schedule.

Best Regards! 
Brian Gohl - AI6US 
(916) 770-7751 cell


-------- Original message --------
From: Jef - N5JEF <jef@...>
Date: 3/3/20 12:39 PM (GMT-08:00)
To: sfarc@w6ek.groups.io, "Dennis Gregory (WU6X)" <wu6x@...>, "Brian Gohl (AI6US)" <ai6us@...>
Subject: Re: [from W6EK Groups.io] NVIS Propagation

Dennis -

I am pleased but surprised by your email and your interest in NVIS at this time. Two years ago, on February 21, 2018, I had requested and argued that #NVIS be one of our group keywords and was denied on the basis of it being "just an antenna technique".

As you might know, my primary interest in ham radio is NVIS because it can provide robust, reliable, regional communications without relying on external infrastructure. 

Attached is a presentation that I prepared and have given as an introduction and overview of NVIS.

- Jef  N5JEF

On Tue, Mar 3, 2020 at 8:41 AM Dennis - WU6X <wu6x@...> wrote:
I haven't paid much attention to NVIS propagation in the past, but now with the BTN antenna I have up, just 6 feet off the ground, I found a few things to be very interesting, and confirmed by this blurb from Idaho ARES:

NVIS propagation is used to fill in between the distance that is normally covered by ground wave and the first hop for low angle of radiation long distance communication. This typically falls between 50 miles and 600 miles.

NVIS is often compared to pointing a shower head straight up at the ceiling and having the water droplets fall everywhere. Counter to most HF antenna installations, NVIS requires a high angle of radiation. This is achieved by installing the antenna at a low height, usually no higher than 1/8 wavelength. Lower antenna heights result in only a slight reduction in received signals and it is not atypical for a portable installation to have the antenna installed just a few feet above the ground.

NVIS does not require a high transmit power level. Power levels of 25 watts are quite effective in maintaining good quality HF communications.

NVIS requires using a frequency that is below the Critical Frequency, the highest frequency at which NVIS communications can operate at, but above the frequency at which the D-Layer absorption results in excessive attenuation, or the Lowest Usable Frequency (LUF). NVIS communications is not possible below the LUF or above the Critical Frequency. Use of frequencies below the LUF or above the Critical Frequency will result in a loss of NVIS communications.

For all practical purposes, NVIS communications at Idaho latitudes rarely are usable at frequencies above 13 MHz as the Critical Frequency rarely climbs above this level.

NVIS HF Propagation is in daily use by United States Military Forces and government emergency agencies at all levels of government on a daily basis. The reason is that it works very reliably.

I'm finding much of this to be very true and very interesting. There are some good points to note and remember as pointed out in this note.

Dennis - WU6X


--
Brian- AI6US

Re: February Breakfast

Brian Gohl - AI6US
 




Best Regards! 
Brian Gohl - AI6US 
(916) 770-7751 cell


-------- Original message --------
From: Dennis - WU6X <wu6x@...>
Date: 3/3/20 7:14 PM (GMT-08:00)
To: sfarc@w6ek.groups.io
Subject: [from W6EK Groups.io] February Breakfast

If you aren’t in this picture, you missed a good one. Maybe see you I’m March?
Dennis - WU6X
--
Brian- AI6US

Upcoming Event: SFARC Net - Thu, 03/05/2020 7:30pm-8:30pm #cal-reminder

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

Reminder: SFARC Net

When: Thursday, 5 March 2020, 7:30pm to 8:30pm, (GMT-08:00) 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!

Upcoming Event: Elmer Net - Wed, 03/04/2020 7:30pm-8:30pm #cal-reminder

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

Reminder: Elmer Net

When: Wednesday, 4 March 2020, 7:30pm to 8:30pm, (GMT-08:00) 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