Re: [Elecraft] KX2/3 DSP AM Demodulation

It's so the roofing filter option can be used (using weaver demodulation). 73 de Matt VK2RQ > On 10 Sep 2017, at 1:39 pm, K9MA wrote: > >> On 9/9/2017 22:13, Don Wilhelm wrote: >> The KX2/3 does not convert directly to audio. >> It converts the RF to "baseband" which is a

[Elecraft] Elecraft CW Net Announcement

Good evening,   The sun has been pretty active this week.  Repeated solar flares have raised the solar flux to 129 and higher.  The auroral oval has calmed to where it's not radiating much noise.  A few days back it was very loud here.  Propagation should be favorable tomorrow.   Some much

Re: [Elecraft] KX2/3 DSP AM Demodulation

On 9/9/2017 22:13, Don Wilhelm wrote: The KX2/3 does not convert directly to audio. It converts the RF to "baseband" which is a zero frequency IF (in the KX3).  The KX2 has the "8kHz shift" built in at all times, so the IF is 8kHz rather than baseband. The KX3 can shift to the 8kHz IF if there

Re: [Elecraft] KX2/3 DSP AM Demodulation

Right, the amplitude of the signal is just the length of the I/Q vector, which is sqrt(I^2 + Q^2). If the receiver is a little off-frequency, the I/Q vector rotates (because the phase is constantly changing) but the amplitude is still just the length of the vector. Alan N1AL On 09/09/2017

Re: [Elecraft] KX2/3 DSP AM Demodulation

Never mind:  I think I found the answer: https://www.tjhsst.edu/~rlatimer/techlab/Gelbpaper04.pdf (The explanation isn't that clear, but I worked through the trig a bit more rigorously, and got the same answer.) Basically, the modulating signal, m, is the square root of the sum of the

Re: [Elecraft] KX2/3 DSP AM Demodulation

Scott, The KX2/3 does not convert directly to audio. It converts the RF to "baseband" which is a zero frequency IF (in the KX3). The KX2 has the "8kHz shift" built in at all times, so the IF is 8kHz rather than baseband. The KX3 can shift to the 8kHz IF if there is breakthrough of AM

Re: [Elecraft] KX2/3 DSP AM Demodulation

Scott, The KX2/3 is not a direct conversion receiver/transmitter. Instead, it has a quadrature mixer which converts the incoming RF into baseband (or 8kHz IF) I/Q streams which is then sent to analog to digital converter. The output of the A to D converter is a 'bunch of bits', which can be

Re: [Elecraft] KX2/3 DSP AM Demodulation

On 9/9/2017 21:35, Fred Jensen wrote:  A DC receiver converts the signal once to audio.  Regardless of the mechanics [which these days can get very complex], that's really all there is. Ah, but the only way direct conversion can convert AM to audio, without some kind of fancy DSP stuff, is

Re: [Elecraft] KX2/3 DSP AM Demodulation

A superhet converts the signal to an intermediate frequency [455 KHz?].  Sometimes it does it more than once, 2 or more IF's, many today have a very high frequency first IF [70+ Mhz].  A DC receiver converts the signal once to audio.  Regardless of the mechanics [which these days can get very

Re: [Elecraft] KXPD3 problems

Is the paddle port set to "Hand key"? Sent from my iPhone ...nr4c. bill > On Sep 9, 2017, at 4:04 PM, Don Butler wrote: > > I think he may be saying that when the KXPD3 is fully inserted the rig goes > into transmit but it works properly when it is pulled out a little

[Elecraft] KX2/3 DSP AM Demodulation

It's been a long time since I studied signal theory in college, but I'm curious as to how AM is demodulated in a direct conversion radio like the KX2/3.  (SSB and CW demodulation I understand.) Does anyone know, or have a reference? 73, Scott K9MA -- Scott K9MA k...@sdellington.us

Re: [Elecraft] OT: Whole House Generator - Update

I switched to gas, and mu bill went from around 200 bucks a month for electric to about 80 in winter... Also my Honda eu2000i now runs the heater. 73s and thanks, Dave NK7Z http://www.nk7z.net On 09/09/2017 03:00 PM, Ron D'Eau Claire wrote: Perhaps it is saying the obvious, but when

Re: [Elecraft] OT: Whole House Generator - Update

Here I am running  the house with a 3000 watt Honda.   We use wood heat primarily so the furnace is no issue.  I don't worry about the water heater  or kitchen stove.  The microwave is on the transfer switch.  The transfer switch is a manually operated with a dozen circuits. Ken WA8JXM On

Re: [Elecraft] Adjusting Audio Level for Digital Modes

Thanks Bret, glad you found success. This note is information to all who are using any soundcard digital modes. This is a situation of having too many controls that do the same thing (adjust the audio level). There are 2 in the computer - soundcard "speaker" level and the WSJT-X "power

Re: [Elecraft] TX Mode issue

Thanks to all who offered suggestions. Rather than many individual replies, I'll just add further comments here. The SS-USB-100 USB-to-Serial converter (Prolific chipset) is definitely bad. As I said it worked fine before but is flaky now. With the Edgeport 4-port, FT8 works fine and I can

[Elecraft] New KX2 firmware available

KX2 firmware rev. 2.79 has several minor improvements, including: - CW sidetone volume can be set much lower - Auto-power-off timer range is now 5 to 100 minutes (was 3-20 minutes) - Filter bandwidth settings modified to prevent degradation of opposite sideband suppression All of these

Re: [Elecraft] Adjusting Audio Level for Digital Modes

That seemed to do the trick Don. Edging the WSJT-X Power Slider down to mid-scale and K3S MIC LINE IN to ~30 gave me the wiggle room to get the 5th bar flashing. In fact, flashing just a bit was less effective than flashing a lot, but still short of solid 5th bar ON. But I guess the 5th bar flash

Re: [Elecraft] Question for SP3 owners

I just treated myself to a pair of SP3s, and I find them very nice speakers. Easy to configure on my K3S and the position to L/R ends of the Elecraft row of P3/K3S/KPA500 give a good stereo effect. Bret/N4SRN -- Sent from: http://elecraft.365791.n2.nabble.com/

Re: [Elecraft] KXPD3 problems

If that is what was being stated, I did not understand "sends" equals "the paddles send OK". If the KX2 is going into full transmit, there is a problem, contact support for assistance. 73, Don W3FPR On 9/9/2017 4:04 PM, Don Butler wrote: I think he may be saying that when the KXPD3 is fully

Re: [Elecraft] OT: Whole House Generator - Update

Yes, Mine is a manual transfer at the mains, I have a night lite on the commercial side to tell me their power is back on. Mel, K6KBE From: Richard Fjeld To: "Charlie T, K3ICH" ; "elecraft@mailman.qth.net" Sent:

Re: [Elecraft] OT: Whole House Generator - Update

Perhaps it is saying the obvious, but when considering the power requirements of a home determine how it is heated. Here in Oregon, in the land served by the Bonneville Hydroelectric dam, a great many homes like mine are heated electrically. We have a forced air system that employs 3 electric

Re: [Elecraft] OT: Whole House Generator - Update

Charlie, The bottom paragraph of your post caught my eye. Transfer switch type can depend upon a generator’s locale. I have seen outdoor generators hard packed with snow internally. I feel better about examining things before start-up. So for home use, I favor manual control. With a manual

Re: [Elecraft] OT: Whole House Generator - Update

On 9/9/2017 10:43 AM, Doug Hensley wrote: I'm was pleased to hear K3, K3S & KX3 owners consistently reporting whatever hash their units were producing had no ill effects on their Elecraft radios during the period their generator was running. It is quite common for generators to produce RF

Re: [Elecraft] KXPD3 problems

I think he may be saying that when the KXPD3 is fully inserted the rig goes into transmit but it works properly when it is pulled out a little ... -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Don Wilhelm Sent:

[Elecraft] kx2 speaker

John, I am an owner of kx2 for a few years. I am amazed by the quality of the kx2 speaker. For such a tiny radio with so little space for a speaker , it is a very well designed construction of the back cover of the radio and the speaker itself! 73 de Linas LY2H On Fri, Sep 8, 2017 at 4:43 AM,

Re: [Elecraft] KXPD3 problems

Ignacy, I have no idea why you would want to operate it when not fully inserted and the securing screws tightened. It does not sound to me as though you have a problem. 73, Don W3FPR On 9/9/2017 3:02 PM, Ignacy wrote: KXPD3 worked well until last week (ES/NO9E). Now as Z3/NO9E, KXPD3 sends

Re: [Elecraft] OT: Whole House Generator - Update

I have a 20KW Generac here at the house and a 22KW Generac at the farm both with AUTO-transfer switches. The 20KW here at the house is Natural Gas and the one at the farm is Propane. I have noticed no issues at either location concerning radio gear. Ed.. AB4IQ -Original Message-

Re: [Elecraft] OT: Whole House Generator - Update

Don’t forget break before make transfer switches. These provide for complete disconnect from one feed for a brief period before connecting to the other. 73 de na6m On 9/9/17, 2:02 PM, "Dr. William J. Schmidt" wrote:

Re: [Elecraft] OT: Whole House Generator - Update

I solved this issue by changing out the power feeds to both my gas heater, and gas hot water heater with AC line pigtails. I just unplug the two devices from the AC mains, and plug them into the generator output lines. I changed my stove to gas, so when there is a power fail, I run

[Elecraft] KXPD3 problems

KXPD3 worked well until last week (ES/NO9E). Now as Z3/NO9E, KXPD3 sends when fully inserted. When partially inserted, it works OK. It seems that the bottom pins in KX3 are a bit lower and the top ones are a bit recessed. But perhaps it was always that way. I tried to open and close the KX3 and

Re: [Elecraft] OT: Whole House Generator - Update

Well there can be a little more to it. With the larger systems there is phasing circuitry (in the generator or the transfer switch: i have both) to detect and switch at zero cross-over point for "bumpless" transfer of power. Causes the least amount of surge and damage. Dr. William J.

Re: [Elecraft] OT: Whole House Generator - Update

It's Generac "Synergy" not syntergy And yes, they just came out with them as their own version of the inverter type generator. I've only seen it listed on a few of their dealers so far. There's nothing magic about wiring a transfer switch. In the larger systems of about 7 - 8 kW and higher, think

Re: [Elecraft] [K2] Q7/Q8 base voltage

Thank You Don and others who replied directly! I checked those resistors to be correct value. This K2 is >3000, so 100 ohms on R60. Then I continued with PA transistor installation. K2 works now, a bit low output on 20 and up. Low bands easily ten watts. I will check BPF tuning later. After I

[Elecraft] OT: Whole House Generator - Update

Someone on the list suggested we post a summary of private responses to us as an alternative, I'm guessing, to members not knowing what was said. In my case, the results don't lend themselves to a simple summary so I am sending this as a fair response to what I learned: 1. I'm quite

Re: [Elecraft] SWR instead of VFO A Frequency

Bob & Don, Thanks for the clarification. Apparently I've always looked at the LP-100A when tuning as I didn't recall that behavior and it struck me. I'll have to re-read the manual, I didn't find SWR mentioned on page 6 but I've missed things before. Thank you for the help! 73, Gary KA1J

[Elecraft] Question for SP3 owners

My current shack speakers need replacing and I read about the SP3s. Aesthetically, no question they are nice and I'm impressed Elecraft contracted a specialist to design them. I don't take the K3 anywhere - just K1! - so ruggedness is not a need. In such a situation have any here bought SP3s

Re: [Elecraft] Adjusting Audio Level for Digital Modes

My testing with WSJT-X (FT8) "tune" for an audio tone, says that any ALC indication at all, no matter where it is, gives exactly the same RF output.  That said, _and this may only apply to my situation, _the signal is cleaner with only three bars lit. I'm seeing 52 Hz spurs at -50 dBc for

Re: [Elecraft] SWR instead of VFO A Frequency

Gary, How are you initiating transmit? That is normal if you are using TUNE. If you are tapping XMIT or closing the Key or closing PTT, the frequency should be displayed. 73, Don W3FPR On 9/9/2017 3:01 AM, Gary Smith wrote: I just changed the configuration to power per band and now when I

Re: [Elecraft] SWR instead of VFO A Frequency

The VFO A display shows the SWR in tune mode. See page 6. -- Sent from: http://elecraft.365791.n2.nabble.com/ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm

Re: [Elecraft] Adjusting Audio Level for Digital Modes

How about using the mouse scroll wheel, it adjusts the power in 0.1dB steps. At least it does on my Win7 box. The waterfall sliders also respond to the scroll wheel. Regards, Mike VP8NO On 08/09/2017 21:52, Bob McGraw K4TAX wrote: As an operational note for WSJT-X.  Version 1.8.0 -rc2 To

[Elecraft] SWR instead of VFO A Frequency

I just changed the configuration to power per band and now when I transmit it shows the numerical value of the SWR instead of the VFO A frequency. I must have accidentally engaged a command while bumping something, looking for PWR SET. Say the frequency showing on VFO-A is 10.11 If I