[Elecraft] Elecraft CW Net Report

[kevinr]

Good Evening,

   Both nets had medium to deep QSB.  Reports of S3 to S7 were common.  
QRN was in a steady hiss with a few crackles of summer storms on 40 
meters.  Hopefully our pleading to the ion provider did not go in vain.  
We may have to sacrifice a metaphor to propitiate it.


  I have a 1965 movie on screen at the moment.  Richard Burton in "The 
Spy Who Came in from the Cold".  I've never seen it before, the B sets 
are crisp and noire.  'M' is playing the local grocer for some silly 
reason.


  I am also reading reviews of an American made Linux box from System 
76.  Good company with solid equipment.  They just work and don't get in 
your way.  I am thinking of upgrading to a larger laptop.  Their OS lets 
me transition from my 3 large monitor environment to a laptop screen 
fairly simply.  A keystroke to migrate from workspace to workspace sold me.



  On 14050.5 kHz at 2200z:

W0CZ - Ken - MN - running from solar power from a campsite in Minnesota

K6XK - Roy - IA - enjoying pleasant temperatures with prospects of rain

K4TO - Dave - KY - back home after a trip, etc.

K0DTJ - Brian - CA - eager to get back to his carpentry


  On 7047.5 kHz at z:

W0?Z - probably Ken but I never got him back again.

K0DTJ - Brian - CA - enjoying a cool breeze

W6JHB - Jim - CA - reconstructing his landscape at 99 degrees

K6PJV - Dale - CA - also doing yard work during temperatures in the high 
90s mourning his lost antenna



  According to SpaceWeather.com we are very close to the bottom of this 
cycle.  We can only go up from here.  By early 2020 we should be seeing 
improved propagation.  Hopefully we shall all be around to see the next 
low point.  By then we'll be using our new K6's :)


   Until next week,

  73,

 Kevin.  KD5ONS









The shoe is on the hand it fits, there's really nothing much to it
Whistle through your teeth and spit 'cause it's alright
Oh well, a touch of grey kinda suits you anyway
And that was all I had to say and it's alright

I will get by
I will get by
I will get by
I will survive

We will get by
We will get by
We will get by

We will survive


{Thanks Jerry}

-




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Re: [Elecraft] Fan for KXPA100

[Edward R Cole]

I mounted my KXPA100 in my truck under the back seat for mobile 
operation.  Ford made a nice lockable compartment accessed by tilting 
up the seat and the amp just fits but the seat bottom rests on the 
top of the heat sink fins.  As we were traveling thru hot weather, I 
was concerned there would be enough air flow so I attached two 1-1/2 
inch square fans on the connector end of the amp to force some air 
thru the fins.  I used the spare power-pole connector for 12v power 
which runs when voltage is applied to the amp.  I also cut several 
3/4 inch holes in the sheet metal seat base for air flow to/from the truck cab.


It survived running 80w on 6m-SSB so guess its enough (I did not monitor temp).

I have the amp connected to the KX3 for remote control (nice when mobile).

Adding a fan to solid state amps is good insurance (esp. when running digital).

73, Ed - KL7UW

Date: Fri, 2 Aug 2019 10:09:54 -0700 (MST)
From: MaverickNH 
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] Fan for KXPA100
Message-ID: <1564765794266-0.p...@n2.nabble.com>
Content-Type: text/plain; charset=us-ascii

Wow - yeah!

Running FT8 30W my KXPA100 is psuging 55C and dropped to 35C with a 3" USB
fan placed on top of the fins. When the shack gets cold this Winter, I may
take the fan off again ;-)

Bret/N4SRN


73, Ed - KL7UW
  http://www.kl7uw.com
Dubus-NA Business mail:
  dubus...@gmail.com 


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Re: [Elecraft] Question about K4HD Xtal filters

[Nr4c]

I believe a similar question was answered a month or so ago. I think the answer 
was “Yes”. K3 filters will work in a K4HD. 

Sent from my iPhone
...nr4c. bill


> On Aug 4, 2019, at 9:44 PM, John K9UWA  wrote:
> 
> So the K4HD will have an SSB and a CW Crystal filter in each of the two 
> receivers. My question since I already have some nice paired filters between 
> my K3 and my K3s can I use those pairs in the new K4HD ?
> 
> thanks
> John k9uwa
> John Goller, K9UWA & Jean Goller, N9PXF 
> Antique Radio Restorations
> k9...@arrl.net
> Visit our Web Site at:
> http://www.JohnJeanAntiqueRadio.com
> 4836 Ranch Road
> Leo, IN 46765
> USA
> 1-260-637-6426
> 
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[Elecraft] Question about K4HD Xtal filters

[John K9UWA]

So the K4HD will have an SSB and a CW Crystal filter in each of the two 
receivers. My question since I already have some nice paired filters between 
my K3 and my K3s can I use those pairs in the new K4HD ?

thanks
John k9uwa
John Goller, K9UWA & Jean Goller, N9PXF 
Antique Radio Restorations
k9...@arrl.net
Visit our Web Site at:
http://www.JohnJeanAntiqueRadio.com
4836 Ranch Road
Leo, IN 46765
USA
1-260-637-6426

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Re: [Elecraft] Aug 2 post of K-line For Sale

[James Rogers]

All items of that post have been spoken for or sold

73s Jim
Sent from Mail for Windows 10

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Re: [Elecraft] 2.8kHz filter needed

[Nr4c]

Most likely source of this will be Elecraft. Those who bought these replaced 
the 2.7 KHz standard filter. You’re more likely to find spare 2.7KHz filters. 

Sent from my iPhone
...nr4c. bill


> On Aug 4, 2019, at 4:58 PM, charlie carroll  wrote:
> 
> I'm looking for 1 or 2 new 2.8kHz, 8 pole filters that might be sitting idle 
> in someone's desk drawer.
> Reply direct to me.
> 
> thanks
> 
> 73 charlie, k1xx
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Re: [Elecraft] K3s and second receiver

[James Rogers]

The item has sold.
 

Sent from Mail for Windows 10

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Re: [Elecraft] K-Pod data cable

[Don Wilhelm]

Jim,

Refer to the K-Pod manual.

You must cut one of the wires to use with the K-Pod.

73,
Don W3FPR

On 8/4/2019 5:55 PM, Jim N7US wrote:

Is the K-Pod's data cable a standard data cable?  I'd like to use one that
is a bit longer than the stock cable so am wondering if I can just
substitute a standard one.

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[Elecraft] K-Pod data cable

[Jim N7US]

Is the K-Pod's data cable a standard data cable?  I'd like to use one that
is a bit longer than the stock cable so am wondering if I can just
substitute a standard one.

 

Jim N7US

 

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Re: [Elecraft] KPA500 PA current

[Jim Brown]

On 8/4/2019 10:57 AM, Jack Brindle wrote:

I have to argue with my friend Jim on this one. The coax itself can be an 
antenna, and can pick up RF along its path from the antenna to the radio.


Yes, it can, and it is good practice to break up feedlines to high 
dipoles to prevent their interaction with adjacent vertical antennas; a 
choke acts as an egg insulator.  I first published this recommendation 
about ten years ago. It is also good practice on long runs from 
receiving antennas to prevent noise and TX RF from coupling to the 
inside of the coax by a limitation of the shield quantified as its 
transfer impedance. This is especially important with the relatively 
thin shields of CATV coax we commonly use for RX antennas, which are 
especially poor shields below VHF. But, again, these chokes should be 
along the line outside the shack.


But NOT on a feedline in the shack! Think about it -- coax feedlines 
should be bonded to the premises ground system at the point of entry.




The best example is a vertical antenna which will use any metal it can find for 
return currents, which includes the coax after the antenna-mounted choke.
An antenna should NEVER depend on the feedline to carry return current, 
and an effective choke prevents this. Further, a path for return current 
should be provided by some sort of counterpoise, the most effective of 
which is a radial system. Also, you're describing a type of vertical fed 
from the base. There are many vertical antennas that approximate center 
feed.  They are discussed in these slides for another talk I've given at 
Pacificon, Visalia, and some ham clubs. 
http://k9yc.com/VerticalHeight.pdf and in this pdf, which ran in The Jug 
several years ago. http://k9yc.com/AntennaPlanning.pdf

This current will combine with the internal shield current at the first place 
they are connected (which very well may be the SO239 on the back of the ATU).


If that's the first point of connection, you've got a VERY unsafe 
station with respect to lightning!  RUN, do not walk, to buy N0AX's 
recent ARRL book on Grounding and Bonding, to which I contributed 
extensively. Or study these slides for a talk I've given at Visalia, 
Pacificon, and several local clubs. You'll find it referenced in Ward's 
book.


http://k9yc.com/GroundingAndAudio.pdf 




A choke at this point will protect against the problem.


The only thing chokes do in the shack is reduce RF current from coupling 
to or from poorly designed equipment by a mechanism called "The Pin One 
Problem" by the audio professional who first described it, Neil Muncy, 
ex-W3WJE (SK) in 1994.  I've seen it in virtually every piece of ham 
gear where I've looked for it, including all the Elecraft products I've 
examined, even the KRC2 band decoder.


73, Jim K9YC
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[Elecraft] 2.8kHz filter needed

[charlie carroll]

I'm looking for 1 or 2 new 2.8kHz, 8 pole filters that might be sitting 
idle in someone's desk drawer.

Reply direct to me.

thanks

73 charlie, k1xx
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[Elecraft] For Sale: K3s 100 W w/second receiver

[James Rogers]

Basic K3s (purchased new 2015) including
KP3A 100 Watt upgrade
KANT3 Antenna connection board (NOT an autotuner)
K3 TCXO .5ppm factory installed
2.8 kHz 8 pole filter upgrade
KRX3A Second Receiver w/ 2.7kHz filter (purchased n ew2018)
USB Cable to computer
DC cable to power strip (powerpole connectors)
All manuals 
Original Cost $3450 
One owner, like new condition
Payment by PayPal $2075 plus shipping from Birmingham AL 35244
For additional info jim.w4atk at gmail.com (cell) 205-520-4530
Photo qth.com item #1450702
Sent from Mail for Windows 10

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[Elecraft] Sunday Elecraft SSB net for 8-4-2019

[Eric Lanzl]

Hello everyone,
Here is the log for today's Elecraft SSB net. The conditions were difficult 
again as there was a lot of QSB and stations were heard and then disappeared. 
Thank you again to the relay stations for your help in receiving stations that 
I could not hear. Thanks to John N6JW, Jim NC0JW, and Roger N4NRW. The net 
meets every Sunday at 1800Z on a frequency of 14.303.5 unless there is a 
contest or an important holiday. All are welcome. 
Eric WB9JNZ Net control station

Elecraft SSB Net 8-4-2019

WB9JNZ Eric  IL    K3    4017    Net Control

NC0JW   Jim  CO  KX3    1356   Relay station

N6PGQ   Bob  CA  K3        5891

K6SF  Guy CA  K3S  10650    

N6JW John    CA   K3          936   Relay Station

K6WDE   Dave   CA KX3        4599

WM6P Steve   GA K3S      11453

W1NGA   AL    CO   K3    5765

W7QHD   Kurt     AZ  K2/100       1538 

N4NRW    Roger  SC   K3        1318  Relay station

AE1E   Ken  NM    K3S  11611

WW4JF        John    TN  K3S  11177 

KE5VDT   Roger  TX     K3        6054

K0JFJ       Nick MN    K3S 11177

K8NU/8        Carl OH/MI  operating remote with an ft891 from KA8UGB

KE0OPG  Fred NB          ICOM 7200

WM6T      Tracy   CA K3S      10299

NS7P   Phil  OR    K3    1826

K6VWE   Stan MI      K3      650

KD0PQX  Mark    CO            ICOM 7300
KD0VNQ      Gerry          Kenwood   TS990
W4DML    Doug   TN     K3     6433

KM4DK     Dirk KY      KX3 3643

KC7FAT    Glenn  CO  KX3   10419

N9VTB  George  IL        NEW TS 450

W2RUN     Jim  MT       KX3         2260
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Re: [Elecraft] KPA500 PA current

[Andy Durbin]

"This is the effect of not being able to obtain perfect components. It is easy 
to forget that the toroid cores used for the inductors vary, as do the windings 
and capacitors. There will be variances because of this which will be different 
from KPA to KPA. They are set up for best case operation, but then as 
components age things will change. As it is, the design is outstanding. With 
efficiencies greater than 50%, the designers did a super job!"

Jack,

I understand that there will be variation between different KPA500.   However, 
2 owners have reported that 20 m stands out as being less efficient than other 
bands.  I was asking if that is typical of all KPA500.   I don't really expect 
to get an answer though as I doubt many owners have test data as comprehensive 
as mine.

I just did a spot check on 20 m and, despite my line voltage being down to 
118.1 V with the high air conditioning load in the area,  I saw 60% efficiency 
with load R 51 X 0.4:

PA voltage=58.9
PA current=13.8
PA input=812
RF out=490
PA diss=322
PA effic=60

Of course this is not typical of normal operating conditions.

73,
Andy, k3wyc





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Re: [Elecraft] KPA500 PA current

[Jack Brindle via Elecraft]

Andy;

This is the effect of not being able to obtain perfect components. It is easy 
to forget that the toroid cores used for the inductors vary, as do the windings 
and capacitors. There will be variances because of this which will be different 
from KPA to KPA. They are set up for best case operation, but then as 
components age things will change. As it is, the design is outstanding. With 
efficiencies greater than 50%, the designers did a super job!

73!
Jack, W6FB


> On Aug 4, 2019, at 10:34 AM, Andy Durbin  wrote:
> 
> "Note that I don’t discount that the 20m LPF is noticeably less efficient 
> than those on the other bands. Each KPA is unique in this sense - we tune the 
> LPFs for best efficiency for each band. I suspect your KPA is just fine, but 
> the more info we get from you, the more we can tell what is going on."
> 
> In the time I have owned and used my KPA500 I have noticed that 20 m band 
> requires a higher drive level than other bands.  This thread prompted me to 
> do some more analysis of data I had recorded last year.   
> 
> Data here - https://tinyurl.com/y5oygtlp
> 
> The data show that my KPA500 is significantly less efficient on 20 m than on 
> the other bands tested.  Is this a characteristic of all KPA500 and, if so, 
> why would that be the case?  Note that my dummy load shows variation of 
> characteristics with frequency and heating.  I have the load complex values 
> for every data point but I used a test run average R and X to name each test 
> plot.  
> 
> 73,
> Andy, k3wyc
> 
> 
> 
> 
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Re: [Elecraft] KPA500 PA current

[Jack Brindle via Elecraft]

I have to argue with my friend Jim on this one. The coax itself can be an 
antenna, and can pick up RF along its path from the antenna to the radio. The 
best example is a vertical antenna which will use any metal it can find for 
return currents, which includes the coax after the antenna-mounted choke. This 
current will combine with the internal shield current at the first place they 
are connected (which very well may be the SO239 on the back of the ATU). A 
choke at this point will protect against the problem. This may not be 
common-mode currents, which is one of the reasons I hesitated in calling it 
that in my previous email.

Perhaps the best way to make sure there is no current flowing on the outside of 
coax shield would be to add ferrites along the entire path, a solution that is 
way to expensive to be practical.

73!
Jack, W6FB

> On Aug 4, 2019, at 10:29 AM, Jim Brown  wrote:
> 
> On 8/4/2019 9:20 AM, Jack Brindle via Elecraft wrote:
>> And, do you have chokes on the coax at the KAT500 or KPA500?
> 
> I hope not -- to be effective, a choke must be that the antenna's feedpoint. 
> A choke on an antenna in the shack does nothing.
> 
> 73, Jim K9YC
> 
> 
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Re: [Elecraft] KPA500 PA current

[Andy Durbin]

"Note that I don’t discount that the 20m LPF is noticeably less efficient than 
those on the other bands. Each KPA is unique in this sense - we tune the LPFs 
for best efficiency for each band. I suspect your KPA is just fine, but the 
more info we get from you, the more we can tell what is going on."

In the time I have owned and used my KPA500 I have noticed that 20 m band 
requires a higher drive level than other bands.  This thread prompted me to do 
some more analysis of data I had recorded last year.   

Data here - https://tinyurl.com/y5oygtlp

The data show that my KPA500 is significantly less efficient on 20 m than on 
the other bands tested.  Is this a characteristic of all KPA500 and, if so, why 
would that be the case?  Note that my dummy load shows variation of 
characteristics with frequency and heating.  I have the load complex values for 
every data point but I used a test run average R and X to name each test plot.  

73,
Andy, k3wyc




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Re: [Elecraft] KPA500 PA current

[Jim Brown]

On 8/4/2019 9:20 AM, Jack Brindle via Elecraft wrote:

And, do you have chokes on the coax at the KAT500 or KPA500?


I hope not -- to be effective, a choke must be that the antenna's 
feedpoint. A choke on an antenna in the shack does nothing.


73, Jim K9YC


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[Elecraft] AX1 Loaded Whip Antenna - Elevation and Counterpoise?

[MaverickNH]

I've got my little 20m AX1 and 3 tuned counterpoise wires on a 4ft tripod
with wires extending to plastic chairs 3ft off the ground too. If I got that
whip up to 2m above ground with sloping wires, would I gain much?

Bret/N4SRN



--
Sent from: http://elecraft.365791.n2.nabble.com/
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Re: [Elecraft] KPA500 PA current

[Jack Brindle via Elecraft]

Tell us a bit more about the antenna. How is it fed? Is it properly choked to 
eliminate RF shield current (this is current flowing on the outside of the 
shield. It is a bit early to remember the proper term…)?
And, do you have chokes on the coax at the KAT500 or KPA500?

I think we need a bit more info to determine what is going on here. RF return 
currents flowing back into the station and combining at the KAT500 connector 
could account for something like this. 
Note that I don’t discount that the 20m LPF is noticeably less efficient than 
those on the other bands. Each KPA is unique in this sense - we tune the LPFs 
for best efficiency for each band. I suspect your KPA is just fine, but the 
more info we get from you, the more we can tell what is going on.

In any case, welcome to Elecraft products! We work hard to bring delight to 
your radio experience.

73!
Jack, W6FB

> On Aug 2, 2019, at 4:03 PM, W4HWD  wrote:
> 
> HI,
> 
> I'm new here and new to Elecraft. I have to KPA/KAT500 combo and love it! I
> do have a question about PA current though...
> 
> On all bands except 20, when running full power out, my HV sits around 64v
> and PA current is stable between 10 and 12A. FAn takes it's time coming on
> and amp just loafs along. On 20, however, even at lower power output levels,
> the PA current is high and the fan comes on and steps up quickly! At full
> 500W out on 20, HV is 62v and current runs as high as 16A! Even at 300w out
> the current runs around 13A, higher than any other band at full 500w out.
> 
> Question is, is this just how it is or do I have something amiss on 20m?
> Antenna is doublet 60' in the air and this antenna is the one I use on 80,
> 40 and 20, so don't think I can blame the antenna. Tuner loafs along during
> all this, and SWR is no worse than 4:1 on any of these three bands.
> 
> Harry W4HWD
> 
> 
> 
> 
> 
> --
> Sent from: http://elecraft.365791.n2.nabble.com/
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Re: [Elecraft] KPA500 PA current

[Don Wilhelm]

Harry,

What is your current draw when connected to a 50 ohm dummy load.
Connect the load to the KPA500 directly (not through the KAT500).

That will tell you whether the KPA500 is OK - and if so, you should 
investigate your antenna impedances - measure with an antenna analyzer.
SWR is not sufficiently informative, you need to know the resistive and 
reactive components of the load to determine whether the KAT500 is 
capable of matching it.
The KAT500 has a nominal matching capability of up to a 10:1 SWR, but at 
very low impedance loads, that can break down.


73,
Don W3FPR

On 8/2/2019 7:03 PM, W4HWD wrote:


On all bands except 20, when running full power out, my HV sits around 64v
and PA current is stable between 10 and 12A. FAn takes it's time coming on
and amp just loafs along. On 20, however, even at lower power output levels,
the PA current is high and the fan comes on and steps up quickly! At full
500W out on 20, HV is 62v and current runs as high as 16A! Even at 300w out
the current runs around 13A, higher than any other band at full 500w out.

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[Elecraft] KPA500 PA current

[Andy Durbin]

"On 20, however, even at lower power output levels, the PA current is high and 
the fan comes on and steps up quickly!"

As Bob has said, KPA500 PA current (also PA dissipation and PA efficiency) are 
strongly dependent of the load presented by the antenna system.   To understand 
what is going on you will need to know the complex load presented to the 
KPA500.  SWR is insufficient to characterize the load.   Avoid any load with R 
significantly less than 50 ohm even if the SWR looks ok.

Some of my test data is shown here - https://tinyurl.com/y37szlko

73,
Andy, k3wyc

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