Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Bill Frantz]

Back in the day, when people used modems with a LED that blinked 
when transmissions were occurring, someone aimed a telescope at 
the LED and was able to intercept the modem's transmission since 
the LED was operated from the output data stream. When people 
started experimenting, data rates of up to 1 megabit/second were 
achieved. Think about the possibilites for field day. :-)


73 Bill AE6JV

On 11/21/17 at 8:34 PM, r...@cobi.biz (Ron D'Eau Claire) wrote:

Fred, it's called LiFi and uses the ability of LED light 
sources to handle high frequency modulation to send data 
securely since one has to intercept the actual beam to even get 
the data, much less decode the information. Apparently pretty 
high data rates are possible with the system.

---
Bill Frantz|"Web security is like medicine - trying to 
do good for

408-356-8506   |an evolved body of kludges" - Mark Miller
www.pwpconsult.com |

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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Walter Underwood]

Perhaps. But when I was doing spook tech in the early 1980’s, modern western 
nations were already using encrypted digital modes. Encryption was strong 
enough that tactical intelligence focused on non-content approaches. 35 years 
later, I would expect that tech to be widespread. Some of what we did showed up 
in HP products only ten years later.

wunder
K6WRU
Walter Underwood
CM87wj
http://observer.wunderwood.org/ (my blog)

> On Nov 21, 2017, at 8:50 PM, donov...@starpower.net wrote:
> 
> Hi Walter,
> 
> Your doubts have no basis in reality.   Many nations -- but not modern
> western nations -- still use Morse for military communications,
> especially tactical comms.
> 
> 73
> Frank
> W3LPL
> 
> From: "Walter Underwood"  >
> To: "Elecraft" >
> Sent: Wednesday, November 22, 2017 4:42:24 AM
> Subject: Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy
> 
> About training intercept operators … I doubt that Morse is used very often by 
> the opposition, even with good code books. But if we stopped training people 
> to read it, that would be a vulnerability.
> 
> wunder
> K6WRU
> Walter Underwood
> CM87wj
> http://observer.wunderwood.org/  (my blog)
> 
> > On Nov 21, 2017, at 8:34 PM, Ron D'Eau Claire  > > wrote:
> > 
> > Fred, it's called LiFi and uses the ability of LED light sources to handle 
> > high frequency modulation to send data securely since one has to intercept 
> > the actual beam to even get the data, much less decode the information. 
> > Apparently pretty high data rates are possible with the system. 
> > 
> > Here's a press article from about a year ago.
> > 
> > http://dailycaller.com/2016/08/10/revamped-100-year-old-lamp-will-help-the-navy-counter-russia-and-china/
> >  
> > 
> > 
> > I'm sure we Hams will find a use for the technology, Hi! 
> > 
> > Way back in 1955 when I was in High School I created a very popular display 
> > that used my S-38 receiver tuned to a popular station. Current powering a 
> > 6V lantern passed through the S38's audio output transformer to modulate 
> > the light. The lighet was received by a photoelectric tube across the 
> > table, amplified and the sound of the radio station played in a remote 
> > speaker. The sound could be interrupted by passing one's hand in from of 
> > the light. 
> > 
> > Even though it was an incandescent bulb with its thermal lag, it still 
> > reproduced good AM quality audio.
> > 
> > It was good enough (in 1955) that I was encouraged to display it at the 
> > annual Science Fair where it worked too well. Someone stole the 
> > photoelectric tube from the display before it could be judged -- but I 
> > still got an A on the project! 
> > 
> > 73, Ron AC7AC
> > 
> > 
> > -Original Message-
> > From: elecraft-boun...@mailman.qth.net 
> >  
> > [mailto:elecraft-boun...@mailman.qth.net 
> > ] On Behalf Of Fred Jensen
> > Sent: Monday, November 20, 2017 12:34 PM
> > To: elecraft@mailman.qth.net 
> > Subject: Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy
> > 
> > OK, what's different then from WW2 signal lamp usage?  I thought they were 
> > using a modified lamp with QRQ Morse decoded in some sort of 
> > hardward/software device, or a digital mode.
> > 
> > 73,
> > 
> > Fred ["Skip"] K6DGW
> > Sparks NV DM09dn
> > Washoe County
> > 
> > 
> > __
> > Elecraft mailing list
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> > 
> > Help: http://mailman.qth.net/mmfaq.htm 
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> 
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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[donovanf]

Hi Walter, 


Your doubts have no basis in reality. Many nations -- but not modern 
western nations -- still use Morse for military communications, 
especially tactical comms. 


73 
Frank 
W3LPL 

- Original Message -

From: "Walter Underwood"  
To: "Elecraft"  
Sent: Wednesday, November 22, 2017 4:42:24 AM 
Subject: Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy 

About training intercept operators … I doubt that Morse is used very often by 
the opposition, even with good code books. But if we stopped training people to 
read it, that would be a vulnerability. 

wunder 
K6WRU 
Walter Underwood 
CM87wj 
http://observer.wunderwood.org/ (my blog) 

> On Nov 21, 2017, at 8:34 PM, Ron D'Eau Claire  wrote: 
> 
> Fred, it's called LiFi and uses the ability of LED light sources to handle 
> high frequency modulation to send data securely since one has to intercept 
> the actual beam to even get the data, much less decode the information. 
> Apparently pretty high data rates are possible with the system. 
> 
> Here's a press article from about a year ago. 
> 
> http://dailycaller.com/2016/08/10/revamped-100-year-old-lamp-will-help-the-navy-counter-russia-and-china/
>  
> 
> I'm sure we Hams will find a use for the technology, Hi! 
> 
> Way back in 1955 when I was in High School I created a very popular display 
> that used my S-38 receiver tuned to a popular station. Current powering a 6V 
> lantern passed through the S38's audio output transformer to modulate the 
> light. The lighet was received by a photoelectric tube across the table, 
> amplified and the sound of the radio station played in a remote speaker. The 
> sound could be interrupted by passing one's hand in from of the light. 
> 
> Even though it was an incandescent bulb with its thermal lag, it still 
> reproduced good AM quality audio. 
> 
> It was good enough (in 1955) that I was encouraged to display it at the 
> annual Science Fair where it worked too well. Someone stole the photoelectric 
> tube from the display before it could be judged -- but I still got an A on 
> the project! 
> 
> 73, Ron AC7AC 
> 
> 
> -Original Message- 
> From: elecraft-boun...@mailman.qth.net 
> [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Fred Jensen 
> Sent: Monday, November 20, 2017 12:34 PM 
> To: elecraft@mailman.qth.net 
> Subject: Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy 
> 
> OK, what's different then from WW2 signal lamp usage? I thought they were 
> using a modified lamp with QRQ Morse decoded in some sort of 
> hardward/software device, or a digital mode. 
> 
> 73, 
> 
> Fred ["Skip"] K6DGW 
> Sparks NV DM09dn 
> Washoe County 
> 
> 
> __ 
> Elecraft mailing list 
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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Walter Underwood]

About training intercept operators … I doubt that Morse is used very often by 
the opposition, even with good code books. But if we stopped training people to 
read it, that would be a vulnerability.

wunder
K6WRU
Walter Underwood
CM87wj
http://observer.wunderwood.org/ (my blog)

> On Nov 21, 2017, at 8:34 PM, Ron D'Eau Claire  wrote:
> 
> Fred, it's called LiFi and uses the ability of LED light sources to handle 
> high frequency modulation to send data securely since one has to intercept 
> the actual beam to even get the data, much less decode the information. 
> Apparently pretty high data rates are possible with the system. 
> 
> Here's a press article from about a year ago.
> 
> http://dailycaller.com/2016/08/10/revamped-100-year-old-lamp-will-help-the-navy-counter-russia-and-china/
> 
> I'm sure we Hams will find a use for the technology, Hi! 
> 
> Way back in 1955 when I was in High School I created a very popular display 
> that used my S-38 receiver tuned to a popular station. Current powering a 6V 
> lantern passed through the S38's audio output transformer to modulate the 
> light. The lighet was received by a photoelectric tube across the table, 
> amplified and the sound of the radio station played in a remote speaker. The 
> sound could be interrupted by passing one's hand in from of the light. 
> 
> Even though it was an incandescent bulb with its thermal lag, it still 
> reproduced good AM quality audio.
> 
> It was good enough (in 1955) that I was encouraged to display it at the 
> annual Science Fair where it worked too well. Someone stole the photoelectric 
> tube from the display before it could be judged -- but I still got an A on 
> the project! 
> 
> 73, Ron AC7AC
> 
> 
> -Original Message-
> From: elecraft-boun...@mailman.qth.net 
> [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Fred Jensen
> Sent: Monday, November 20, 2017 12:34 PM
> To: elecraft@mailman.qth.net
> Subject: Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy
> 
> OK, what's different then from WW2 signal lamp usage?  I thought they were 
> using a modified lamp with QRQ Morse decoded in some sort of 
> hardward/software device, or a digital mode.
> 
> 73,
> 
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
> 
> 
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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Ron D'Eau Claire]

Fred, it's called LiFi and uses the ability of LED light sources to handle high 
frequency modulation to send data securely since one has to intercept the 
actual beam to even get the data, much less decode the information. Apparently 
pretty high data rates are possible with the system. 

Here's a press article from about a year ago.

http://dailycaller.com/2016/08/10/revamped-100-year-old-lamp-will-help-the-navy-counter-russia-and-china/

I'm sure we Hams will find a use for the technology, Hi! 

Way back in 1955 when I was in High School I created a very popular display 
that used my S-38 receiver tuned to a popular station. Current powering a 6V 
lantern passed through the S38's audio output transformer to modulate the 
light. The lighet was received by a photoelectric tube across the table, 
amplified and the sound of the radio station played in a remote speaker. The 
sound could be interrupted by passing one's hand in from of the light. 

Even though it was an incandescent bulb with its thermal lag, it still 
reproduced good AM quality audio.

It was good enough (in 1955) that I was encouraged to display it at the annual 
Science Fair where it worked too well. Someone stole the photoelectric tube 
from the display before it could be judged -- but I still got an A on the 
project! 

73, Ron AC7AC
  

-Original Message-
From: elecraft-boun...@mailman.qth.net 
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Fred Jensen
Sent: Monday, November 20, 2017 12:34 PM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

OK, what's different then from WW2 signal lamp usage?  I thought they were 
using a modified lamp with QRQ Morse decoded in some sort of hardward/software 
device, or a digital mode.

73,

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


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Re: [Elecraft] Digitized IF over IP?

[Fred Jensen]

Yes, 1st IF normally feeds a P3 at around 8 MHz thru a short length of 
RG-58.


Yes, the BW at the 1st IF is quite wide, limited only by the front end 
BPF.  After down conversion to baseband [or something close, 15 KHz 
comes to mind [:-)] it would need bandlimiting before the ADC.  That's 
not at all unheard of.  50 KHz BW would be fine with me, I'd settle for 
20 KHz.


Yes, I know where the roofing filters are and they're not relevant here, 
the P3 sees the signal chain before them in a local environment.


The P3, in a purely local environment, has access to the K3 via the CAT 
port which tells it where VFO A and B are tuned, thus permitting Fixed 
Tune mode where the P3 cursor follows the "Big Knob."  That would be 
really cool in the remote environment.


There are many non-P3 solutions here ... I have a P3 ... first plan 
would be to get it to work remotely.  I will try running the K3 CAT port 
thru the P3 to the RRC-1258 and see if that still works remotely and 
what the P3 does with all the Microbit chatter on the cable.


Lots of good info and ideas coming out of this.  Thanks to all

73,

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

On 11/21/2017 2:20 AM, Edward R Cole wrote:
I"m not sure what bw you are requiring for IP, but I assume you are 
talking about the 1st IF of the K3 or K3s.


You do realize that its very wideband at that point.  Roofing filters 
follow the 1st IF to feed the 2nd IF and DSP ckts.  I run two LP-Pan 
from the IF of both my main and subRx on the K3.  Input bw of the 
LP-Pan is 400-KHz and can provide 196-KHz IQ baseband output.  I also 
have a SDR-IQ with max bw of 190-KHz.  I only utilize that bw when 
measuring sun noise on 1296; normal bandpass for monitoring is 100-KHz 
which covers eme sub-bands.  For MAP65 I only monitor 60-KHz 
(144.095-144.155 MHz); Map65 takes output of two LP-Pan into a Delta44 
soundcard which has 96 KHz bw.  My emu0202 can do 196 KHz but run from 
K3 audio out its limited to 4-KHz bw.


I would guess the 1st IF would receive bw of a complete band (28-30 
MHz on 10m).


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


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[Elecraft] FLDIGI on Raspberry Pi PTT issue with the K2

[Elmore's]

Please carefully read everything that follows to avoid repetition of the steps 
followed. What I have summarized here is the result of MANY hours of work and 
extensive troubleshooting time via email with 2 incredibly helpful and patient 
hams.

I have an RPi 3 with FLDIGI and WSJT-X installed.

After MUCH effort over the past 6 months I have WSJT-X working. My problem now 
is that the PTT on the FLDIGI does not work.

The PTT on the WSJT-X does work. It's underlying rig control is Hamlib. I am 
using the Elecraft USB to serial adapter connected to the proprietary K2 serial 
cable.

Note that I have successfully used the K2 with a Windows PC running FLDIGI and 
WSJT-X for some time.

I have configured FLDIGI for RigCAT. It communicates with the K2 (frequency, 
mode, filter selection) but no PTT.

I have also tried Hamlib but it will not initialize.

During an extensive troubleshooting process over the past 3 weeks with a ham on 
the Yahoo FLDIGI RPi group I tried FLRIG. It is fully functional with the K2 
but when I try using it with FLDIGI nothing works – no frequency control, no 
PTT, nothing! By this I mean that I am trying to use FLDIGI for the control. I 
have verified that I have all the correct settings in both FLDIGI and FLRIG 
with the ham that has been helping me. As a sanity check I installed FLRIG on 
my Windows machine and successfully ran FLDIGI there.

Has anyone had similar issues?

Thanks for any help.

73,
Jim WA4YWM

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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Bob McGraw K4TAX]

A relatively new ham asked for a copy or diagram of my portable antenna 
design.   Here's my response.




Welcome on being a new ham.  As to the antenna design..well 
there is no such thing in existence.


We usually camp in National parks and State parks.  There's usually a 
few to a lot of trees around.  I carry a 100 ft spool of #22 insulated 
hookup wire wound on a plastic spool.  That was the way I purchased 
it.   Once the travel trailer is in position, I will scout out a nice 
tree limb some 15 to 30 ft off of the ground.  I then unroll about 50 to 
75 ft or so of the wire from the spool, drop a half hitch around the 
spool to prevent the remainder of the wire from rolling off of the 
spool.  Using a method similar to that of "David when he slew the 
Giant", I hurl the spool over a limb.  Of course sometimes my estimated 
distance or height is in error and I find it necessary to make another 
attempt or two.  The spool and wire simply keep the wire taught over the 
limb and to the trailer.  On the trailer, I have a feed through which 
was originally for a TV antenna, no longer used for that purpose.  To 
this I attach the end of the wire to the F connector.  Inside I have a 
length of RG 58 coax that runs to the F connector and terminates into a 
BNC connectro.  This attaches to my home made L network for the tuner.  
The L network is comprised of a single variable C of about 500 pF and an 
air wound inductor which is  1 1/2" in diameter and about 6" long.  I 
have a 20 position tap switch that is configured so I can use individual 
tap or select turns of the inductor.  This is mounted in a4" x 4" x 8" 
aluminum  box with a BNC on each end.    I recall having about every 2 
turns tapped to the switch.  Using this L network I can find a point of 
C and L values which produce suitable SWR, less than 2:1 for my 
operation.   After all my RG-58 is only 6 ft long so there is little 
loss on HF in the "feed line".   If this doesn't find a match, I just 
reverse the IN and OUT to provide a different impedance range.     
Should I then have difficulty in obtaining a match, I will loosen the 
wire, allow more to spool off and then try again.   Usually a length of 
some 50 to 75 feet will work about any band except 160 M.   I need more 
wire for that. When we are finished camping, I turn the end of the wire 
loose at the trailer allowing the spool and wire to fall to the ground, 
wind it up and stow it for the next adventure.    All of this is best 
described as an end fed long wire with a L matching network.    There is 
nothing exotic about it, no baluns, no specific lengths, just use the 
wire length and space available.


In reading the various posts and opinions on the topic, I'm amazed at 
the lengths, expense and trouble many hams go to in order to put up an 
antenna.


Hope this helps

***

73

Bob, K4TAX


On 11/21/2017 6:06 PM, Ignacy wrote:

Antenna performance does not depend on how it is fed (if feeder losses are
low) but on height and ground type. For KX3 with AT, any special length
makes little sense, especially in portable conditions. KX3 matches most
random wires, and KX3 with 4:1 balun matches any wires. Lack of balance is
not too important with battery operation. I try to make random wire +
counterpoise at least 1/4 wave on the lowest frequency for reasonable
efficiency.

For 1.5 KW, an endfed with a 49:1 or so transformer makes lots of sense as
wideband tuners for QRO are rare, expensive and heavy. "Myantennas.com"
perfected a  transformer that has very small losses and does not
self-destroy at high power. But in inv V configuration, it is way down from
a flattop.

Ignacy, NO9E



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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Ignacy Misztal]

I tested the endfed from myantennas at 1 kw. The transformer was only warm
so no significant losses there. The feeder was RF hot so a toroid choke was
added. Cable no longer hot and toroid cold. SWR low on many bands. So the
only significant losses could have been through the ground.

This is obvious after a bit of thought. A vertical or inv L ( or low inv V)
needs either good ground or lots of radials for small ground losses. With
endfed, there is one radial, the feeder. So excellent performance by the
beach, not bad in good ground, so so in poor ground.

Ignacy

On Nov 21, 2017 7:58 PM, "Erik Basilier"  wrote:

Ignacy,
For an end-fed wire, I would see the possibility of power losses not only in
the feed feeder, but also in the tuner, the transformer, and the effective
counterpoise path. For low counterpoise losses, small counterpoise current
is desirable, which means a high antenna impedance. When a long counterpoise
wire is needed, and when that wire is close to the ground, I would also
expect ground losses from the counterpoise current interacting with the
ground, in addition to the ground losses caused by the antenna wire
interacting with the ground. When the feeder (outside or shield)-tuner-radio
path carries all or part of the counterpoise current, I would not rule out
the possibility that the possibiility that the resistance there is
sufficient to cause losses significant enough to affect overall efficiency
of the system. That is why I would like to compare like antennas with
different feed systems. Of course antenna wire configuration is the most
important thing to determine overall performance, but when putting up a long
wire, I usually start with the support structure that already exists, or
that I can put up most easily.

73,
Erik K7TV

-Original Message-
From: elecraft-boun...@mailman.qth.net
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Ignacy
Sent: Tuesday, November 21, 2017 5:07 PM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30

Antenna performance does not depend on how it is fed (if feeder losses are
low) but on height and ground type. For KX3 with AT, any special length
makes little sense, especially in portable conditions. KX3 matches most
random wires, and KX3 with 4:1 balun matches any wires. Lack of balance is
not too important with battery operation. I try to make random wire +
counterpoise at least 1/4 wave on the lowest frequency for reasonable
efficiency.

For 1.5 KW, an endfed with a 49:1 or so transformer makes lots of sense as
wideband tuners for QRO are rare, expensive and heavy. "Myantennas.com"
perfected a  transformer that has very small losses and does not
self-destroy at high power. But in inv V configuration, it is way down from
a flattop.

Ignacy, NO9E



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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Don Wilhelm]

Erik,

About all you can conclude from the WSPR readings is the relative 
difference between antennas.  If you want to compare two horizontal 
antennas, place them end to end.  The radiation at the end is at a 
minimum and the antenna will not interact.


As for comparing a vertical with a horizontal antenna, or two verticals, 
the only thing one can say is at that particular time and distance for 
propagation, one antenna is better than the other.  That may not be true 
for other propagation conditions, so be careful when generalizing.


As far as two horizonal antennas oriented in different directions, you 
would expect greater signal strength in directions broadside to the 
antenna.  That directivity may be useful in actual use, but is not a 
valid comparison between the two antennas.


73,
Don W3FPR

On 11/21/2017 8:40 PM, Erik Basilier wrote:

I hope my interest in WSPRLite antenna comparisons doesn't lead this thread too 
far off topic, but I have further thoughts on how to orient the two antennas 
being compared.

Frank, who is much more experienced with this comparison system, suggested that 
two horizontally polarized antennas should be oriented end-to end, due to 
parasitic interacton between the antennas. I questioned whether the end-to-end 
configuration would be free from interactions. Be that as it may, but while 
thinking about configuration choices, I came up with another reason why 
end-to-end would be the right thing to do.

Suppose we are comparing two omnidirectional antennas such as verticals. Even 
if the receiving stations are unevenly distributed in different directions, the 
comparison based on received reports should be fair. If instead we are 
comparing two horizontal dipoles, that are not pointing in the same direction, 
and receiving stations are not distributed evenly in all directions, the 
antenna with fewer receivers in the main lobes would likely be at a 
disadvantage. If the feed system is the part that is different between the two 
ontennas, one could compensate, as I suggested, by swapping antennas for each 
feed system, but the time taken allows the conditions to change, so one would 
probably have to go back and forth a number of times to gain confidence in any 
observed difference in performance. Close to the coast receiving stations would 
be largely missing in roughtly half of possible compass directions, and 
unidirectional antennas would be affected more than a dipole with its bid

irectional pattern. Much seems to depend on the proprietary algorithm used to 
composite a single performance number for from the WSPR received s/n rations at 
multiple receiving stations. What is the balance between the number of good 
reception reports vs. the distance for each one? When we talk about difficulty 
in comparing one vertical and one horizontal antenna, I suspect that similar 
considerations may account for result being inconsistent or difficult to 
interpret.



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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Erik Basilier]

I hope my interest in WSPRLite antenna comparisons doesn't lead this thread too 
far off topic, but I have further thoughts on how to orient the two antennas 
being compared.

Frank, who is much more experienced with this comparison system, suggested that 
two horizontally polarized antennas should be oriented end-to end, due to 
parasitic interacton between the antennas. I questioned whether the end-to-end 
configuration would be free from interactions. Be that as it may, but while 
thinking about configuration choices, I came up with another reason why 
end-to-end would be the right thing to do.

Suppose we are comparing two omnidirectional antennas such as verticals. Even 
if the receiving stations are unevenly distributed in different directions, the 
comparison based on received reports should be fair. If instead we are 
comparing two horizontal dipoles, that are not pointing in the same direction, 
and receiving stations are not distributed evenly in all directions, the 
antenna with fewer receivers in the main lobes would likely be at a 
disadvantage. If the feed system is the part that is different between the two 
ontennas, one could compensate, as I suggested, by swapping antennas for each 
feed system, but the time taken allows the conditions to change, so one would 
probably have to go back and forth a number of times to gain confidence in any 
observed difference in performance. Close to the coast receiving stations would 
be largely missing in roughtly half of possible compass directions, and 
unidirectional antennas would be affected more than a dipole with its 
bidirectional pattern. Much seems to depend on the proprietary algorithm used 
to composite a single performance number for from the WSPR received s/n rations 
at multiple receiving stations. What is the balance between the number of good 
reception reports vs. the distance for each one? When we talk about difficulty 
in comparing one vertical and one horizontal antenna, I suspect that similar 
considerations may account for result being inconsistent or difficult to 
interpret.

73,
Erik K7TV

-Original Message-
From: elecraft-boun...@mailman.qth.net 
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Erik Basilier
Sent: Sunday, November 19, 2017 11:13 PM
To: donov...@starpower.net; elecraft@mailman.qth.net
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30

Hi Frank,

 

Thanks for your very useful comments. Below my answers:

 

>Radiation results from RF current flowing in an antenna.  An RF

>ammeter is a useful instrument for measuring the relative efficiency

>different types of matching networks feeding similar antennas.

Granted. I might want to add that to my plans. I know that the WSPRLite 
tolerates no more than 100 mW of reflected power, and to avoid accident risk I 
intend to set the transmit power to no more than 100 mW. I do not know how the 
units might fold back transmit power in a scenario where the SWR is good but 
less than perfect. For this reason I am planning to use a tuner whenever SWR is 
not very close to ideal. The location of the tuner would be wherever it would 
make sense to place it in field operation. If I add ammeters, they would be 
placed at the feedpoint, which should work well when I compare different 
impedance transformers using identical wires. If I compare to non-resonant 
wires or center feed, it would be hard to compare ammeter readings.

 

> 1.  The two antennas under test should be located within less than

>one wavelength of each other, otherwise independent selective fading

>becomes a significant source of measurement error.  

Interesting. You are saying that this applies even if the comparison is done 
over several hours?

In my limited back yard, and because I want the feedpoints close to each other, 
I will certainly meet the requirement of staying withing one wavelength.

 

>2;  Horizontally polarized antennas should be oriented end-to-end

>to each other to avoid significant parasitic interaction that washes

>out the other differences in antenna performance

My earlier comments about end-fed antennas focused on vertical wires since the 
thread originator had tall trees that suggest vertical orientation. My 
preferred 24” support poles used with 60+ ft wires lead me to the inverted vee 
configuration which will be horizontally polarized. I am surprised that you can 
avoid parasitic interaction if you place the wires end-to-end. I was under the 
impression that end-to-end vertical wires, as in an elevated vertical with a 
resonant length of vertical feedline under it, with a common mode choke 
preventing current going from the radiator to the coax shield, would still 
suffer from parasitic coupling unless an additional common mode choke is added 
somewhere along the feedline to break up the resonance. I am influenced here by 
a QST article about vhf/uhf verticals where it seemed that multiple common mode 
chokes were found necessary to prevent feedline radiation. 

Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Erik Basilier]

Ignacy, 
For an end-fed wire, I would see the possibility of power losses not only in
the feed feeder, but also in the tuner, the transformer, and the effective
counterpoise path. For low counterpoise losses, small counterpoise current
is desirable, which means a high antenna impedance. When a long counterpoise
wire is needed, and when that wire is close to the ground, I would also
expect ground losses from the counterpoise current interacting with the
ground, in addition to the ground losses caused by the antenna wire
interacting with the ground. When the feeder (outside or shield)-tuner-radio
path carries all or part of the counterpoise current, I would not rule out
the possibility that the possibiility that the resistance there is
sufficient to cause losses significant enough to affect overall efficiency
of the system. That is why I would like to compare like antennas with
different feed systems. Of course antenna wire configuration is the most
important thing to determine overall performance, but when putting up a long
wire, I usually start with the support structure that already exists, or
that I can put up most easily.

73,
Erik K7TV

-Original Message-
From: elecraft-boun...@mailman.qth.net
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Ignacy
Sent: Tuesday, November 21, 2017 5:07 PM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30

Antenna performance does not depend on how it is fed (if feeder losses are
low) but on height and ground type. For KX3 with AT, any special length
makes little sense, especially in portable conditions. KX3 matches most
random wires, and KX3 with 4:1 balun matches any wires. Lack of balance is
not too important with battery operation. I try to make random wire +
counterpoise at least 1/4 wave on the lowest frequency for reasonable
efficiency. 

For 1.5 KW, an endfed with a 49:1 or so transformer makes lots of sense as
wideband tuners for QRO are rare, expensive and heavy. "Myantennas.com"
perfected a  transformer that has very small losses and does not
self-destroy at high power. But in inv V configuration, it is way down from
a flattop.

Ignacy, NO9E  



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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Ignacy]

Antenna performance does not depend on how it is fed (if feeder losses are
low) but on height and ground type. For KX3 with AT, any special length
makes little sense, especially in portable conditions. KX3 matches most
random wires, and KX3 with 4:1 balun matches any wires. Lack of balance is
not too important with battery operation. I try to make random wire +
counterpoise at least 1/4 wave on the lowest frequency for reasonable
efficiency. 

For 1.5 KW, an endfed with a 49:1 or so transformer makes lots of sense as
wideband tuners for QRO are rare, expensive and heavy. "Myantennas.com"
perfected a  transformer that has very small losses and does not
self-destroy at high power. But in inv V configuration, it is way down from
a flattop.

Ignacy, NO9E  



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Re: [Elecraft] (OT) - Unplanned Discovery

[Ignacy]

How much noise from "warts" enters the antenna depends on the antenna. Close
and low antenna will pick up more and high and far will pick up less or
nothing. Also, balanced or with a good balun will pick up less than
unbalanced or where KX3 is a counterpoise.  

Ignacy, NO9E   



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Re: [Elecraft] Elecraft Digest, Vol 163, Issue 25

[Frank Meacher via Elecraft]

International Morse

Sent from my iPhone

> On Nov 20, 2017, at 8:02 PM, elecraft-requ...@mailman.qth.net wrote:
> 
> Send Elecraft mailing list submissions to
>elecraft@mailman.qth.net
> 
> To subscribe or unsubscribe via the World Wide Web, visit
>http://mailman.qth.net/mailman/listinfo/elecraft
> or, via email, send a message with subject or body 'help' to
>elecraft-requ...@mailman.qth.net
> 
> You can reach the person managing the list at
>elecraft-ow...@mailman.qth.net
> 
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Elecraft digest..."
> 
> 
> Today's Topics:
> 
>   1. Re: O.T. Morse is not dead, at least in the U.S. Navy
>  (Fred Jensen)
>   2. Walwarts - linear supplies (N2TK, Tony)
>   3. Re: Walwarts - linear supplies (JT Croteau)
>   4. Re: Walwarts - linear supplies (Joe Subich, W4TV)
>   5. Re: Digitized IF over IP? (Jim Miller)
>   6. Re: Walwarts - linear supplies (Jim Brown)
>   7. Re: Digitized IF over IP? (Tom)
>   8. Re: Walwarts - linear supplies (N2TK, Tony)
>   9. Re: Digitized IF over IP? (Fred Jensen)
>  10. Re: Digitized IF over IP? (Jim Miller)
>  11. Re: Digitized IF over IP? (Don Wilhelm)
>  12. Re: Walwarts - linear supplies (Ron D'Eau Claire)
>  13. Re: [KX2] Cannot turn off switch cw tones (Don Wilhelm)
>  14. Re: Digitized IF over IP? (Jim Miller)
>  15. Re: [KX2] Cannot turn off switch cw tones (Wayne Burdick)
>  16. Re: Digitized IF over IP? (tomb18)
>  17. Re: Digitized IF over IP? (Richard Ferch)
>  18. Re: Digitized IF over IP? (Walter Underwood)
>  19. Re: K3 speaker with Remoterig (Rick Tavan)
>  20. K1 Fix and Align (Thom)
>  21. Re: Digitized IF over IP? (Fred Jensen)
>  22. Re: K1 Fix and Align (Don Wilhelm)
>  23. Re: Walwarts - linear supplies (Brian Hunt)
>  24. Re: Digitized IF over IP? (Jim Miller)
> 
> 
> --
> 
> Message: 1
> Date: Mon, 20 Nov 2017 12:33:51 -0800
> From: Fred Jensen 
> To: elecraft@mailman.qth.net
> Subject: Re: [Elecraft] O.T. Morse is not dead, at least in the U.S.
>Navy
> Message-ID: <54a61b5a-3bfc-0788-8818-d7752c5af...@foothill.net>
> Content-Type: text/plain; charset=utf-8; format=flowed
> 
> OK, what's different then from WW2 signal lamp usage?? I thought they 
> were using a modified lamp with QRQ Morse decoded in some sort of 
> hardward/software device, or a digital mode.
> 
> 73,
> 
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
> 
>> On 11/19/2017 6:48 PM, dyarnes wrote:
>> Fred and All,
>> 
>> I think Morse is exactly what they are using with the signal lamps.  The 
>> article I read about this confirmed that.
>> 
>> Dave W7AQK
>> 
>> 
>> 
>> -
>> 
>> There was a recent URL posted involving using the venerable signal
>> lamps for high speed communications between ships.? I don't think it was
>> Morse however.
>> 
>> 73,
>> 
>> Fred ["Skip"] K6DGW
>> Sparks NV DM09dn
>> Washoe County
>> 
>> __
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>> Message delivered to k6...@foothill.net
>> 
>> 
>> --
>> This message has been scanned by E.F.A. Project and is believed to be clean.
>> 
>> 
>> 
> 
> 
> 
> --
> 
> Message: 2
> Date: Mon, 20 Nov 2017 15:37:08 -0500
> From: "N2TK, Tony" 
> To: 
> Subject: [Elecraft] Walwarts - linear supplies
> Message-ID: <011b01d3623f$57a88540$06f98fc0$@verizon.net>
> Content-Type: text/plain;charset="us-ascii"
> 
> I believe recently there was talk about noise from walwarts.  Jameco
> Reliapro offers a line of linear regulated walwarts. They are reasonable in
> price and so far noise free.
> 
> They range from 2-24VDC with .2-1A output.
> 
> N2TK, Tony
> 
> 
> 
> --
> 
> Message: 3
> Date: Mon, 20 Nov 2017 15:57:08 -0500
> From: JT Croteau 
> To: elecraft@mailman.qth.net
> Subject: Re: [Elecraft] Walwarts - linear supplies
> Message-ID:
>
> Content-Type: text/plain; charset="UTF-8"
> 
> They are nice warts Tony.  I have a 1A 12VAC Jameco Reliapro wallwart
> for my beverage direction controller.  It is extremely clean and noise
> free.
> 
> 73
> N1ESE
> 
>> On Mon, Nov 20, 2017 at 3:37 PM, N2TK, Tony  wrote:
>> I believe recently there was talk about noise from walwarts.  Jameco
>> Reliapro offers a line of linear regulated walwarts. They are reasonable in
>> price and so far noise free.
>> 
>> They range from 2-24VDC with .2-1A output.
>> 
>> N2TK, Tony
>> 
>> 

Re: [Elecraft] Walwarts - linear supplies

[Victor Rosenthal 4X6GP]

I've added regulators and (when needed) rectifiers to wallwarts. I just 
put the components on a piece of perfboard, cut the wire, hook it up and 
tape the board to the wart. Presto, a regulated linear wallwart.



73,
Victor, 4X6GP
Rehovot, Israel
Formerly K2VCO
http://www.qsl.net/k2vco/
On 21 Nov 2017 10:43, Jim Brown wrote:

On 11/20/2017 5:50 PM, Brian Hunt wrote:
Be careful using the non-regulated linear wall warts. The open circuit 
voltage can be more than 16 VDC and could be harmful to gear not rated 
that high.


Yes and no.  The vast majority of linear wall warts are UN-regulated, 
but the current drawn by the equipment being powered significantly 
reduces the output voltage, usually to the rated value. That's how 
linear, unregulated power supplies work. That's why it's good to match 
both rated voltage and current. AND -- most equipment will tolerate 
moderate over-voltage. The K3, for example, is rated for 15VDC max.


And, or course, not all gear runs on 12VDC -- lots of stuff runs on 5V, 
7.5V, 9V, and 14V.



Best to measure OC first!


Measuring OC is a good thing, and EXPECT to see 25-30% higher voltage 
than rated. But what matters is the voltage under load. And that's why 
my applications note recommends putting Power Poles on both the wart and 
the connector to the equipment, then sticking a voltage monitor in line 
with the equipment connected. You did read the link I posted, didn't 
you?  :)


73, Jim K9YC

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Re: [Elecraft] Walwarts - linear supplies

[Larry (K8UT)]

Two years ago, I embarked on a "wallwart-ectomy" in my shack, removing 
all wall warts and replacing them with DC power cords that connected to 
fused dc power strips, connected to a single shack linear supply. Band 
decoder, PC speakers, SDR Rx, wavenode wattmeter... none of those items 
have their own power source any more.



-larry (K8UT)

-- Original Message --
From: "Joe Subich, W4TV" 
To: elecraft@mailman.qth.net
Sent: 2017-11-20 16:17:02
Subject: Re: [Elecraft] Walwarts - linear supplies



All Electroncs (www.allelectronics.com) has analog wall warts of 
various

voltage/current capability depending on what is available in surplus at
any given time.  One may not even need regulated voltage as many 
devices

contain internal regulators ...

They presently show 12 V @ 500 mA and 12.5V @ 410 mA units that appear
to be analog for less than $5.00 each in Q=1.

73,

  ... Joe, W4TV


On 11/20/2017 3:37 PM, N2TK, Tony wrote:

I believe recently there was talk about noise from walwarts.  Jameco
Reliapro offers a line of linear regulated walwarts. They are 
reasonable in

price and so far noise free.

They range from 2-24VDC with .2-1A output.

N2TK, Tony

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Re: [Elecraft] Digitized IF over IP?

[Edward R Cole]

I"m not sure what bw you are requiring for IP, but I assume you are 
talking about the 1st IF of the K3 or K3s.


You do realize that its very wideband at that point.  Roofing filters 
follow the 1st IF to feed the 2nd IF and DSP ckts.  I run two LP-Pan 
from the IF of both my main and subRx on the K3.  Input bw of the 
LP-Pan is 400-KHz and can provide 196-KHz IQ baseband output.  I also 
have a SDR-IQ with max bw of 190-KHz.  I only utilize that bw when 
measuring sun noise on 1296; normal bandpass for monitoring is 
100-KHz which covers eme sub-bands.  For MAP65 I only monitor 60-KHz 
(144.095-144.155 MHz); Map65 takes output of two LP-Pan into a 
Delta44 soundcard which has 96 KHz bw.  My emu0202 can do 196 KHz but 
run from K3 audio out its limited to 4-KHz bw.


I would guess the 1st IF would receive bw of a complete band (28-30 
MHz on 10m).


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


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Re: [Elecraft] Walwarts - linear supplies

[Jim Brown]

On 11/20/2017 5:50 PM, Brian Hunt wrote:

Be careful using the non-regulated linear wall warts. The open circuit voltage 
can be more than 16 VDC and could be harmful to gear not rated that high.


Yes and no.  The vast majority of linear wall warts are UN-regulated, 
but the current drawn by the equipment being powered significantly 
reduces the output voltage, usually to the rated value. That's how 
linear, unregulated power supplies work. That's why it's good to match 
both rated voltage and current. AND -- most equipment will tolerate 
moderate over-voltage. The K3, for example, is rated for 15VDC max.


And, or course, not all gear runs on 12VDC -- lots of stuff runs on 5V, 
7.5V, 9V, and 14V.



Best to measure OC first!


Measuring OC is a good thing, and EXPECT to see 25-30% higher voltage 
than rated. But what matters is the voltage under load. And that's why 
my applications note recommends putting Power Poles on both the wart and 
the connector to the equipment, then sticking a voltage monitor in line 
with the equipment connected. You did read the link I posted, didn't 
you?  :)


73, Jim K9YC

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