Re: [Elecraft] Anew k3 owner de ai5os.

it). I'd expect the response to be 10s of dB down before 500 Hz, maybe over 60. -- David Woolley __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft

Re: [Elecraft] KAT 500 Loses Match

the transmit path.) -- David Woolley On 14/01/2024 05:16, Ken WA8JXM wrote: Unless its something like a log periodic, I think anything with those frequency/SWR specs can only do it with high resistive losses.  It reminds me of the HF dipole B makes for the military: it is designed to appear to have

Re: [Elecraft] K2 SSB Power Overshoot on First Syllable

instances, would end up too high, so as not to limit the maximum output. I believe there is a gain calibration procedure on the K3 and K4, that allows those to make a reasonable open loop power setting at the start of a transmission. -- David Woolley (owner K2 06123) On 18/12/2023 22:42, Karin

Re: [Elecraft] Noise from KAT500?

Most switch mode supplies have transformers. The weight differences reflects the difference between a large mass of laminated iron, and a, small, ferrite toroid. Using a higher frequency allows a less bulky transformer. -- David Woolley On 03/12/2023 04:54, David Gilbert wrote: The ones I

Re: [Elecraft] [OT] A dumb question about lightning

rocess will be complicated, and there will be a significant random element, but the presence of grounded conductors will have an effect in the very early stages. -- David Woolley On 28/07/2023 22:46, Walter Underwood wrote: Lightning can’t tell whether something is grounded because the energy

Re: [Elecraft] Where to put the wattmeter

I'm fairly sure that (forward power) - (reverse power) gives the correct nett output power, before cable and antenna losses. I'd need to review the maths to be sure. Most reflected power ends up re-re-reflected, as additional forward power. A high SWR will giver reflected power almost as

Re: [Elecraft] KX3 and SWR

might survive a very high SWR for some loads, but be very fussy for other ones. -- David Woolley On 16/03/2023 15:58, Ingo Meyer DK3RED wrote: The KX3 should tolerate an SWR of 1.6:1. I have already unintentionally transmitted with my KX3 (5W CW) without antenna and the KX3 is still in good

Re: [Elecraft] Win4K3 - Virtual COM Ports on Windows 10

is not backed by large hardware sales to fund this process. Any approval is likely to be for a single version, not for the open source project as a whole. -- David Woolley On 15/01/2023 15:27, John Overbaugh wrote: I'm trying to set up my KX3 on a new Windows 10 computer using Win4K3. Has anyone

Re: [Elecraft] KPA1500 Faulting for High SWR inappropriately

). But this means that the same SWR can be completely safe or destroy a PA, depending on the phase information. -- David Woolley __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm

Re: [Elecraft] [K2] CAL-PLL Question

of the induced currents, in the bottom panel, flowed through these points to make a difference. -- David Woolley Owner K2 06123 On 30/07/2022 16:25, Wolfgang wrote: in a german QRP forum I found this hint from Peter, DL2FI (SK).    In any case, the PLL calibration must be redone whenever

Re: [Elecraft] Using the Antenna Tuner in the XPA100

t type design would give 500, 1,000, and 1,500. I guess capacitors were expensive. -- David Woolley On 02/07/2022 23:13, Mister Mike wrote: The 180S-1 consists of an L network which is formed by a variable air-capacitor on the input, and a variable roller inductor as the serie

Re: [Elecraft] I need a Sherlock Holmes (weird spurs on 40m)

. -- David Woolley On 08/06/2022 09:22, Dynolab wrote: Your 24kHz spaced spurs from 6.6 MHz to 7.4MHz sounds very much like Orthogonal Frequency Division Multiplexing (OFDM). A secure type of modulation encryption that is often used on the HF bands for High Frequency securities trading

Re: [Elecraft] Troubleshooting KIO2

Arduinos use an AtMega microcontroller chip, rather than the FTDI chip. Before considering alternatives, do beware of the the vulnerable, Auxbus, signal on the non-standard K2 connector. My PC motherboard was selected because it had a real RS232C asynchronous port. -- David Woolley Owner K2

Re: [Elecraft] K3 and Kenwood MC-50 mike

the effective output impedance. -- David Woolley On 11/04/2022 16:37, Joe Subich, W4TV wrote: On 2022-04-11 10:55 AM, David Woolley wrote: RF PAs are also, typically, much lower impedance than their design load. Except they *DO HAVE* impedance matching - typically a broadband output transformer (4

Re: [Elecraft] K3 and Kenwood MC-50 mike

RF PAs are also, typically, much lower impedance than their design load. -- David Woolley On 09/04/2022 18:23, Jim Brown wrote: RF impedances ARE matched. Audio impedances are NOT. Low-Z out, high Z in. __ Elecraft mailing list

Re: [Elecraft] KPA500 Issue

will have infinite side bands, but by correct shaping you can make them very small.) -- David Woolley Owner K2 06123. On 01/04/2022 23:06, Jim Brown wrote: On 4/1/2022 2:35 PM, kevin wrote: It is more accurately referenced as Discontinuous Wave. Actually, it is 100% amplitude modulation

Re: [Elecraft] K2 advice needed - what to buy

Mic%20Jack.pdf>. PS. Starting a subject with Re, when it is not a reply, will be scored as possible spam by some spam filters. -- David Woolley Owner K2 06123 On 23/11/2021 11:57, E J Martin wrote: I have a long wire resonant (SWR < 1.4) across the 40 band hence don't nee

Re: [Elecraft] Headphones for Hearing Loss

, the standard correction applied by hearing aids is approximately half the number of dB's of loss. They don't try to fully cancel the loss. -- David Woolley On 14/10/2021 00:24, Jim Brown wrote: First, one that works for K6DGW, who mostly works CW and has a lot of hearing loss. Set RXEQ

Re: [Elecraft] K2/100 RS232 trouble

some pins unconnected. -- David Woolley Owner K2 06123 On 10/09/2021 13:12, Andy McMullin wrote: You are using the special RS232 cable aren’t you? You must connect with a cable matching the special pinout first. If you try a straight connection it will fail

Re: [Elecraft] I Keep Getting Kicked Out

. Nearly all the spam detections, I see for the list, are false positives. I take it in MIME digest format, however, sometimes posts from legitimate members get forged onto the list. -- David Woolley On 23/07/2021 01:51, kg6mzs wrote: I keep getting kicked off the reflector for the stated reason

Re: [Elecraft] The next generation KAT500

of the reverse coupler, as, once you have an in range SWR, you can use a minimum finding algorithm to home in. Incidentally, if you do need to do a brute force search, using a Gray code progression will be kinder on the relays than linear sweeps. Some of this may actually already be being done. -- David

Re: [Elecraft] Generic words on temperature

100°F is well within the survivable body core temperature range, so it should never trigger pain receptors. In fact, I believe it was defined based on the nominal core body temperature of a cow. Did you mean 100°C? -- David Woolley On 04/07/2021 00:03, Francis Belliveau wrote: Another

Re: [Elecraft] Temperature or Warmth of KPA500 when "Off" ?

I don't think this design would be acceptable in modern consumer equipment, at least not in Europe. Typically they would have an auxiliary power supply for the microcontroller, to reduce power consumption to well under 1 watt, and maintain a reasonably good power factor, when in a soft power

Re: [Elecraft] Roofing filters and DSP bandwidth tuning

passband ripples and will have non-linear phase responses, which can compromise digital modes. At least some of the DSP filters are finite impulse response, meaning they are also linear phase, which means that pulses will not get smeared out. -- David Woolley

Re: [Elecraft] Headphones for Hearing Loss

bluetooth. Incidentally, it may well not be well known, but hearing aid prescriptions generally under-compensate by about a factor of two in the dB values, so an aid for a 60dB loss would, typically, only have 30dB gain at the frequency in question. -- David Woolley On 26/01/2021 16:22, Joseph

Re: [Elecraft] [K4] IF Out

The K4 doesn't have an IF, so it can't have an IF output! Did you mean the K4D, although, admittedly, it might use the same box? -- David Woolley On 21/01/2021 00:45, john wrote: The K4 does not appear to have an IF Out connector on the rear panel, like the K3. Can the XVTR IF Out

Re: [Elecraft] Arecibo antenna collapses

, is why they went for a spherical, rather than a parabolic, shape. -- David Woolley On 02/12/2020 17:22, Andrew Faber wrote: So by moving the cabin and pulling on cables, they can apparently track through about 20 degrees, unlike Arecibo, which is fixed in a spherical shape

Re: [Elecraft] Firmware development

, largely, use the printer to make the printer, so they attracted people who wanted to flash their own firmware. -- David Woolley On 27/11/2020 04:26, SteveL wrote: I own a popular open-source based 3D printer. Finding the firmware to run the printer reliably is a challenge. Once found (or so I

Re: [Elecraft] k2 spurious

. The alternative ratio doesn't transform the filter input impedance down so much. I mention this as there is a common misconception that the "maximum power transfer theorem" actually applies in such cases, when applying it would produce less than 50% efficiency. -- David Woolle

Re: [Elecraft] Smoke detectors

is that they are cheap. -- David Woolley On 25/10/2020 10:36, Geoffrey Feldman wrote: The reason to keep smoke detectors from Amateur Radios is that they detect smoke by ionization from a radioactive source. A strong near field will set them off. The good news is that this is your indication

Re: [Elecraft] K3, k4 Black knobs

d LEDs, but rather those with the longest wavelength consistent with an adequate remaining cone cell sensitivity. See <https://midimagic.sgc-hosting.com/huvision.htm> for typical colour sensitivity curves. -- David Woolley On 16/10/2020 14:31, Ken B wrote: Why do you use red  and not b

Re: [Elecraft] K4 sound card capability

As there is not even a block diagram published, I don't know the answer, but ideally one would not want baseband analogue audio anywhere in the path, so one would not want a sound card, integrated or not, but rather direct access to a digital feed from the DSP. On 04/10/2020 20:07, Terry

Re: [Elecraft] New KX3 reverse voltage smoke

See page 3 of for confirmation that the KX3 chassis is connected to the the same network as the negative supply to the internal components. On 05/09/2020 19:32, Alan - G4GNX wrote: I'd be very surprised if

Re: [Elecraft] New KX3 reverse voltage smoke

is being interconnected with equipment on another power supply. If the safety earth rises significantly above that of other conducting items during a fault, there is a defect in earth bonding in the installation as a whole, that needs urgent rectification. -- David Woolley Owner K2 06123

Re: [Elecraft] W1 Programming???

device (mouse/keyboard) class. As such, the ability to write code for the thumb drive doesn't mean you can use the same code on the wattmeter, even though the chances are that the USB side can be treated as though it were something else. -- David Woolley Owner K2 06123. On 05/09/2020 01:57

Re: [Elecraft] K2 transmit limitations

I don't believe there is any ability to frequency restrict the K2. It's essentially a bag of components, and most countries allow licensed amateurs to home construct from components, and applying hard limits in such cases would be difficult. On 09/08/2020 08:29, Ingo Meyer, DK3RED wrote:

Re: [Elecraft] Matching resonant antennas

You can only have a 1:1 SWR at a single impedance. If the design impedance is purely resistive, that means you can only have 1:1 for a resistive and therefore on-resonance load (or one that can be treated as having no reactive behaviour at the frequencies of interest - e.g. an ideal dummy

Re: [Elecraft] Copying CW at high speeds

com/NervousSystem/nerveimpulses.htm#impulsespeed> -- David Woolley On 29/12/2019 03:27, Kevin McQuiggin wrote: It does not negate the argument, but nerve impulses are based on chemical reactions in neurons, and only travel at about 120 metres per

Re: [Elecraft] Dual panadapter on K4 at Pacificon

the leadership of David Mills W3HCF. The reference version means the version used to verify the implementability of the specification in the RFC document. -- David Woolley Owner K2 06123 On 18/10/2019 23:31, David Gilbert wrote: Agree about Windows.  When I power on my Win10 laptop that I use

Re: [Elecraft] test

or other rich text versions. I think the list software is stripping out the text/html variant, rather than rendering the HTML as plain text. -- David Woolley On 23/07/2019 18:51, RALPH TURK wrote: This is a test of HTML

Re: [Elecraft] OT a bit: K3 Ant Tuner

ading to antenna. Another reason for not operating anywhere near 50 ohm reverse terminated is that the dynamic resistance of output devices is far from linear, and a close match could produce a lot of distortion. -- David Woolley Owner K2 06123 On 05/07/2019 18:55, Jack Brindle wrote: Lets

Re: [Elecraft] Elecraft KX4

of the internet (before commercialisation) were radio amateurs. One of the big reasons that we have TCP/IP now and not something based on X.25, and the OSI model, is the open source nature of the key implementations. -- David Woolley On 01/07/2019 19:10, Alan wrote: The software was copyrighted

Re: [Elecraft] K4 pre-distortion?

, not to change a signal from unreadable to readable. -- David Woolley On 16/06/2019 07:39, Dave wrote: The K3 noise reduction is very poor, I have never found it useful on SSB, and certainly not on CW. __ Elecraft mailing list Home: http

Re: [Elecraft] Help with IF Noise, DSP Noise, NR settings

the narrower filters on the main path. That will happen with single, or randomly spaced spikes. -- David Woolley K2 06123 On 13/06/2019 14:09, Bob McGraw K4TAX wrote: The Noise Blanker only affects repetitive pulse noise such as ignition type noise.  Lightning and atmospheric is random noise

Re: [Elecraft] K4: superhet vs. direct sampling

On 05/06/2019 13:23, W2xj wrote: Direct sampling has no image issues. That's because they are called aliasing issues! -- David Woolley __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http

Re: [Elecraft] The K4's new noise reduction

There is a good reason why cross-posting email is a bad idea. This failed on elecraft...@groups.io Could anyone replying please use just the standard elecraft list. On 31/05/2019 21:22, David Woolley wrote: I would think that, at best, there would be no  benefit over using a fixed filter

Re: [Elecraft] The K4's new noise reduction

close to that ideal. -- David Woolley Owner K2 06123 On 31/05/2019 18:13, John Stengrevics wrote: The K3S’ NR algorithm is not operable on digital modes. Will that be the case on the K4 as well? __ Elecraft mailing list Home: http

Re: [Elecraft] Reflector format

, so you may have to do an extra move. Except for a bug that doubles Re: in the subject line, you can pull out individual messages even with bare bones Thunderbird, and reply to them with correct threading. -- David Woolley On 21/05/2019 21:28, Don Wilhelm wrote: If you receive the individual

Re: [Elecraft] Sensitivity - Was K4 Observations

used, e.g. the number of bits actually represented by a call sign is log2 (number of possible callsigns) and the number encoded in FT8 is log2 (number of active FT8 callsigns). -- David Woolley Owner K2 06123 On 19/05/2019 19:15, Joe Subich, W4TV wrote: There is one place that digital modes (

Re: [Elecraft] K4 Observations

the Elecraft desginers will have is setting the price point. -- David Woolley Owner K2 06123 On 19/05/2019 04:09, Buck wrote: The radio is full SDR as opposed to the analog front end of the K3. However an option, the K4HD, is a superhet receive function.  Like previous Elecraft radios, this can be added

Re: [Elecraft] Measuring SWR (Long)

A typical transmitter does not reverse terminate the transmission line with its characteristic impedance, so most of the reflected power gets re-reflected as forward power. Reflected power isn't necessarily lost power. At least at lower frequencies, it is likely to present a much higher

Re: [Elecraft] Tinnitus and the K3 RX EQ and Related Variables

I would expect an audiologist to consider 3kHz as a high frequency, as they are generally interested in speech intelligibility, and hearing aids are not, generally, high bandwidth devices. It's also high in musician's terms, being three and a bit octaves above middle C. Someone with age

Re: [Elecraft] Macintosh version of Elecraft KX3 Utility

I assume you mean that has been compiled for, as if you can compile it you can probably compile if for many different architectures. However ARM is not a single machine type. There are many different ARM family devices with different instruction sets. You would probably want a specific

Re: [Elecraft] KXPA100 Input Current vs Output Power

Whilst I can't give you quantitative answers, I would expect there to be a constant term and a square root power term, so my guess is that 50W would take about 80% of the 100W current and 10W about 38-40%. These are peak envelope currents. -- David Woolley Owner K2 06123 On 22/03/2019 14:51

Re: [Elecraft] Setting band edges on the K3

limits based on the destination country, although I don't think they can cope with essentially spot allocations. I believe there are ways of changing the allocations in the field, but they are not in the public domain and users have to demonstrate authorisation for the frequency. -- David

Re: [Elecraft] Query for new DSP features

the parameters on the fly. On 15/01/2019 02:53, Wes Stewart wrote: https://www.youtube.com/watch?v=FrVDL_-HOds starting at 41 minutes. Particularly at 1 hour 3 minutes. On 1/12/2019 9:51 AM, David Woolley wrote: Do you have a reference for an algorithm that will do

Re: [Elecraft] New DSP Idea

adapter FFTs don't need to run overlapping transforms. I think the big question is does the machine have enough processing power to do this. -- David Woolley Owner K2 06123 On 13/01/2019 01:06, David Gilbert wrote: these things: 1.  Actually amplify a desired signal (probably 2 to 3 db

Re: [Elecraft] Query for new DSP features

follows, as well as what precedes.) As a caution, I believe the K3 has two different noise handling strategies: the one I am talking about here, and one designed to deal with impulse noise, where you simply cut out a short section of signal around the noise pulse. -- David Woolley Owner K2

Re: [Elecraft] KAT 500 and open wire

Don: 1) made a distinction between feedpoint and load impedance, which led me to believe the load was the antenna, and the feedpoint the transmitter end; 2) said that the feedpoint impedance depended on the length of the line and the frequency, which further supported that interpretation.

Re: [Elecraft] KAT 500 and open wire

load on 300 ohm feeder will have a feed point impedance that swings from 75 to 1200 ohms. -- David Woolley Owner K2 06123 On 06/01/2019 21:40, Don Wilhelm wrote: The feedpoint impedance to the transmission line can vary from quite low to quite high dependent on the frequency, the length of line

Re: [Elecraft] How to unsubscribe from reflector?

On 30/12/2018 00:04, W2xj wrote: Work for most large media companies worth billions and writing down passwords will have security escorting you out of the building, a lost pension and a major followup security investigation. Passwords have become unworkable as a security measure. Too many

Re: [Elecraft] K2 with KPA-100

Unfortunately the KAT100-2 doesn't seem to be available any longer, even though it is still described on the man page for the tuner. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help:

Re: [Elecraft] Noise-cancelling headphones mystery

of the source. -- David Woolley Owner K2 06123. On 09/12/2018 16:40, CUTTER DAVID wrote: ncies. If your hearing takes you higher, the noise-cancelling has finished by then. This is probably not the ability of the sensing mic but the circuitry and/or room acoustics, echo, etc. I'm a little out

Re: [Elecraft] FS: New CM500 headset

theatre audiences, but eventually are sold cheaply to TV stations). Also the service costs in prescribing and maintaining can be high. For the NHS these dominate the cost of the physical instruments. -- David Woolley On 28/11/2018 02:48, John Simmons wrote: A friend of mine told me about

Re: [Elecraft] FS: New CM500 headset

of a challenge, as they are designed to pass the low frequencies directly and only amplify the high ones. -- David Woolley Owner K2 06123 On 27/11/2018 01:20, Edward R Cole wrote: > Firstly, I have extreme hearing loss. Without my Phonac-Silvia hearing > aids the world it very quiet.

Re: [Elecraft] [K2] External Fan Hum

ctances gets to them. -- David Woolley Owner K2 06123 On 07/11/18 14:56, Don Wilhelm wrote: The DC fan may have a magnetic field, but it would be constant instead of alternating polarity 120 times a second. __ Elecraft mailing list Home: ht

Re: [Elecraft] CODEC

But if they want to install a third party time sync program they are better off installing W3HCF's definitive implementation of the NTP protocol, rather than a program that was, I believe, really designed for Windows 3.1/95. In 06/10/18 21:15, Larry (K8UT) wrote: The user has two choices: use

Re: [Elecraft] CODEC

There should be very little reason to use Dimension 4, with step updates at fixed intervals. The full implementation of ntpd is available for all the Windows NT family, i.e. everything after Windows 95, and versions or w32time that can be configured to implement the older version of NTP have

Re: [Elecraft] Mail List Procedure Question

e to which they are responding. That cuts short the next digest and also forces one to plough through lots of old postings, possibly to find that the culprit has overflowed the digest size limit and there are no more real items in the digest.) -- David Woolley Owner K2 06123 On 30/06/18 15:09,

Re: [Elecraft] KPA-1500 ATU not working well

I'm not clear whether you are talking about the SWR before or after the tuner, but efficiency is determined by the load seen by the PA, which has two degrees of freedom (reactance and resistance), both of which can vary either side of the ideal. SWR reduces this to a single variable, that

Re: [Elecraft] K2 Build: Options Advice

dummy version of most of the modules, but the sales of the K2 dropped to a level where it wasn't worth another production run for the PCBs for this. -- David Woolley Owner K2 06123 On 24/05/18 19:44, AE0MM wrote: I'm planning to build a K2/10 with the following options: KNB2 KAT2 KAF2

Re: [Elecraft] KPA500/K3 AUX bus specification

You would need to sign a non-disclosure agreement for anything beyond the logic level (TTL) and pinout information. I've never heard of one being given out for this purpose. -- David Woolley Owner K2 06123 On 29/04/18 21:59, ANDY DURBIN wrote: Can someone please point me to a definition

Re: [Elecraft] current flow on copper strips

. The field density is proportional to the current, so the current will be concentrated near the major axes end points. -- David Woolley Owner K2 06123 On 27/04/18 23:47, Alan B wrote: My thinking is the current density is uniform in the outer surface of a round tube falling according to skin depth

Re: [Elecraft] The new KX19

tries to disappear on a near parabolic orbit, except for being slightly limited by air resistance. -- David Woolley Owner K2 06123 (low mass and power by design) On 01/04/18 18:56, kevinr wrote: Antigravity mods let you take the KX19 on camping trips, ocean cruises, or even pedestrian mobile

Re: [Elecraft] KX3 Utility Segmentation Fault in Linux

That is much more serious than a warning. I'd expect it to be immediately followed by a crash with signal 3 (abort), rather than signal 11 (segmentation fault). However, if this isn't the standard assert routine, I would expect any attempt to actually use hash_table to produce a segmentation

Re: [Elecraft] KPA1500 and FT8

I believe at least some of the DSP filters in the K3 are FIR (Finite Impulse Response) ones, which should be phase linear. The roofing filters will not be phase linear, so I would think you could get away with using a narrow DSP filter, as long as you used a relatively wide roofing filter.

Re: [Elecraft] PA Transistors Maintenance in K2

their job and mounted the transistor properly with the correct torque on the mounting hardware procedure, no additional maintainance is required. -- David Woolley K2 06123 __ Elecraft mailing list Home: http://mailman.qth.net/mailman

Re: [Elecraft] KX3 with BL2 Question

hat the common mode current sees more of a real than imaginary impedance. -- David Woolley K2 06123 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elec

Re: [Elecraft] Items you think you can depend on

But the electrons only get less than a micron back before they get sent forward again, and they've only had about 1/120th of a second to rest. You are lucky they are not unionised, with those working conditions! -- David Woolley K2 06123 On 04/09/17 19:09, Ken K6MR wrote: Yes, but those

Re: [Elecraft] Items you think you can depend on

* computer equipment. The former is actually designed for 13.8V with a wide tolerance, although mainly downwards. The latter is designed for 12.0V with a tolerance of maybe 5%, and expectations of rather better. Depending on what it contains, it may actually tolerate a rather wider range. -- David

Re: [Elecraft] K3S Noise reduction Test

mixed up human speech form the other people in the restaurant. -- David Woolley K2 06123 On 20/06/17 20:44, GRANT YOUNGMAN wrote: You might want to look at actual (S+N)/N data. I’m not sure the visual “test” tells the full story, since these are complex waveforms. I did extensive measurement

Re: [Elecraft] [K3S] JT65-HF Beginner

with an operating system (e.g. the standard C library). Some tools put a significant amount of template code into the output, but those are normally licensed under LGPL, rather than GPL. -- David Woolley K2 06123 On 28/05/17 16:32, Kevin Stover, AC0H wrote: If the program was written with GPL tools

Re: [Elecraft] [KPA1500] Input Power

not until they have approval. I notice total silence from the insiders on this, and the previous similar thread. -- David Woolley K2 06123 On 13/05/17 15:59, Dr. William J. Schmidt, II wrote: So are you saying that the KPA500 is a bad design? I'm not aware of a single non-CB amplifier

Re: [Elecraft] [KPA1500] Input Power

not be easy. You can assume that CB users wanting to use illegal powers have access to soldering irons. Also, I would assume that the design gain is actually less than 15dB, to allow for component tolerances. -- David Woolley K2 06123 On 12/05/17 02:43, Dr. William J. Schmidt wrote: All of those

Re: [Elecraft] Another really good reason to come to the Visailia DX convention this weekend...

stive load. -- David Woolley K2 06123 On 25/04/17 04:51, Jim Brown wrote: The reason for using 240VAC is to reduce the IR drop in the AC line, which, BTW, is not sinusoidal, but rather pulses that charge the filter caps at the peaks of each cycle. So the drop in the wire is even greater than Ohm's la

Re: [Elecraft] KPA1500 amplifier with built-in ATU, separate power supply

straight back out again when it hits the PA, to get another chance to be lost in the feeder, or even radiated. Of course this may cause the PA to run out of volts, or gain, and clip or distort, or exceed the safe operating area, and melt bond wires, or destroy the chip itself. -- David Woolley

Re: [Elecraft] KPA-1500: Gain Mod when FCC Lifts 15db Rule

As I understand the way things work, they will not get approval for the device, if it is easily modifiable to defeat the current limit, so I would expect them to play down any modifiability even if it can't be classed as easy. -- David Woolley K2 06123 On 21/04/17 11:43, Richard Thorne wrote

Re: [Elecraft] A little theory.

I believe people are confusing Feynman and Sagan. I think it was Carl Sagan who demonstrated the sloppy practices with combination locks and did the Challenger enquiry. I did read some of Feynman's lectures, in high school. -- David Woolley K2 06123 tOn 17/04/17 02:32, k...@juno.com wrote

Re: [Elecraft] Amber display for the K2?

er's part number for that. -- David Woolley K2 06123 On 05/04/17 22:15, Don Wilhelm wrote: Tom, The LCD display on the K2 has "been what it was" from the beginning (even for Field Test units). The backlighting is white (LEDs, not incandescent), but the color of the actual display is gr

Re: [Elecraft] What caused long reposts

the bother of deleting a lot of information. I do not receive email on a smartphone, so I don't have any suggestions for handling that. -- David Woolley K2 06123. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinf

Re: [Elecraft] Future KX3/KX2 accessories?

Computerised language translation is predicated on good continuous speech recognition. For a long time that is going to rely on relatively clean audio. Even if automated translation in noise becomes possible, with the amount of noise, etc., on an amateur radio circuit, the additional

Re: [Elecraft] K2 main encoder wanted

WD40 is a preservative, not a lubricant. It will act as a penetrating oil, to free seized parts, but for a longer term solution you want to look at sewing machine or hair clipper oil. On 25/03/17 20:57, Bob G3PJT wrote: I have managed to get the encoder turning reasonable freely. I put a

Re: [Elecraft] Dimmable LED desk lamp

The light from white "LEDs" is a mixture of a fairly narrow, blue, peak, direct from the LED, and a broad, low, yellow one from the phosphor. The fact that they don't excite the phosphor with UV is one of their advantages, when compared with CFLs (where the actual physics is also pretty much

Re: [Elecraft] Dimmable LED desk lamp for operating position recommendation needed

There will be a switching converter on any quality make of LED lighting. The only way you avoid it is if they use a simple series dropper resistor, which is not energy efficient. LEDs are constant current devices, so there is no such thing as a 12V LED (an LED with a 12V forward voltage drop

Re: [Elecraft] [K3] The Way We Rank Receivers (long)

The main commercial interests in subjective audio noise reduction, particularly for speech, are probably the hearing aid industry. It is subjective because noise reduction only really removes noise that isn't interfering. That is still useful, as whilst the human brain can also do that, it

Re: [Elecraft] Mag Loop

You can put away the tin foil! The lines of force arriving thousands of miles away are not going through your loop; they are closed loops that are no more than half a wavelength across in the direction of travel. That's the difference between near and far fields. On the other hand, that

Re: [Elecraft] K3/K3S noise blanker performance greatly enhanced (at my QTH) -- need testers

be the ultimate solution for hearing aids, as well. -- David Woolley Owner K2 06123 On 06/02/16 03:35, drewko wrote: I'm glad that noise solutions are being investigated. I think advances in NR/NB would be of more importance to many hams than close-in dynamic range, however useful the improvement

Re: [Elecraft] Long RS232 Runs - RS422

, although they are out of specification. ITU-T V.28 is generally aligned with the electrical characteristics of EIA232, but has the advantage that the document is available for free download. -- David Woolley Owner K2 06123 On 21/01/16 20:03, Cliff Frescura wrote: RS-232 use +3 to +15VDC

Re: [Elecraft] K3S RS232 "Y" Connector causing port conflict

, at least, appears to be non-compliant. It looks like the K3 has the same non-compliance. -- David Woolley Owner K2 06123 On 14/12/15 23:08, Don Wilhelm wrote: AFAIK the IBM PC was the first to use the DE-9 connector for the serial port connector, and they initially envisioned the PC being used

Re: [Elecraft] Receivers?

l%20Block%20Diagram.pdf>. There are likely other places, including a better K3 image. -- David Woolley Owner K2 06123 On 11/12/15 21:40, Ron D'Eau Claire wrote: The K3 and K2 and conventional superhetrodyne formats with an Intermediate Frequency in the H.F. range and crystal filters to set the pass

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