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

2017-11-21 Thread 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

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

2017-11-21 Thread 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

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

2017-11-21 Thread 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"

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

2017-11-21 Thread 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,

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

2017-11-21 Thread 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

Re: [Elecraft] Digitized IF over IP?

2017-11-21 Thread 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

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

2017-11-21 Thread 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.

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

2017-11-21 Thread 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

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

2017-11-21 Thread 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

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

2017-11-21 Thread 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

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

2017-11-21 Thread 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

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

2017-11-21 Thread 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

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

2017-11-21 Thread 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

Re: [Elecraft] (OT) - Unplanned Discovery

2017-11-21 Thread 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 -- Sent from:

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

2017-11-21 Thread 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 >

Re: [Elecraft] Walwarts - linear supplies

2017-11-21 Thread 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

Re: [Elecraft] Walwarts - linear supplies

2017-11-21 Thread 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

Re: [Elecraft] Digitized IF over IP?

2017-11-21 Thread 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

Re: [Elecraft] Walwarts - linear supplies

2017-11-21 Thread 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