Re: [Elecraft] Extra Protection For KPA500?

[Tony]

All:

Thanks for the advice regarding protection for the KPA500. I use more 
than one rig with my KPA500 so one has to pay attention to the drive 
levels. I suspect the protection circuit could fail if you accidentally 
pump 100 watts into the amp now and then.


Regarding the K3S power-per-band setting: it looks like it requires the 
LOCK function to keep the power level one chooses. Is that the way it 
works or is there another option besides LOCK?


Tony

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Re: [Elecraft] Extra Protection For KPA500?

[Bob McGraw K4TAX]

Set the K3 or K3S TUNE power to 10 to 20 watts.  I use 18 watts which drives my 
amp to 500 watts.   
Then set the Power Per Band for the required value to produce 500 watts.   

Then and this is a big THEN..turn on the Ext ALC in the transceiver and 
CORRECTLY calibrate the ALC value in the amp menu for the correct level for 
EACH band.  This is very important.  It does work correctly if calibrated and 
used correctly.  That is what it is there for.  I’ve done it, I’ve measured it, 
and it works. 

Abuse it, incorrectly calibrate it, and suffer the consequences.  It is an 
operator issue and not an equipment issue. So don’t blame the equipment. 

Bob, K4TAX


Sent from my iPhone

> On Mar 5, 2020, at 4:53 PM, Don Wilhelm  wrote:
> 
> Curiosity is getting the best of me --
> If the built-in protection works well, why do you need more protection?
> If the belt works OK, then why add suspenders as well?
> 
> If you are operating a K3 or K3S, there is a per band power level that can be 
> used.  It will automatically use the settings for the amplifier when the 
> KPA500 is set to operate.  That can be considered your 2nd level of 
> protection and it guards against "fumble fingers"
> 
> 73,
> Don W3FPR
> 
>> On 3/5/2020 2:35 PM, Tony wrote:
>> All:
>> I'd like to avoid the inevitable situation where one mistakenly transmits 
>> too much power into an amplifier. I have a KPA500 and the protection circuit 
>> works well, but I was wondering what can be done to add an extra layer of 
>> protection?
>> Tony
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Re: [Elecraft] Extra Protection For KPA500?

[Michael Walker]

Hi Tony

You do realize that the KPA500 does have over power protection as well?

Mike va3mw

On Thu, Mar 5, 2020 at 6:17 PM Don Wilhelm  wrote:

> Rick,
>
> When you move into the new shack location, consider getting the new AUX
> cables from Elecraft.  If your original ones have a large (about 1/4
> inch diameter) cable, the new ones are smaller and more flexible.
>
> 73,
> Don W3FPR
>
> On 3/5/2020 5:57 PM, Rick Bates, NK7I wrote:
> > Don et al,
> >
> > On occasion the signal that the amp goes into Operate mode is not passed
> > along (or received, I don't know which), which means that the K3 will
> > operate at higher than required drive level, for a moment only because
> > the KPA500 will fault VERY quickly protecting everything.
> >
> > However, I am unable to come up with a viable pair of suspenders, so I
> > simply try to be more aware when the amp goes hot.
> >
> > The reverse can be true too; the K3 thinks the amp is still in operate
> > (but it isn't) and transmits at lower than expected output.
> >
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Re: [Elecraft] Extra Protection For KPA500?

[Don Wilhelm]

Rick,

When you move into the new shack location, consider getting the new AUX 
cables from Elecraft.  If your original ones have a large (about 1/4 
inch diameter) cable, the new ones are smaller and more flexible.


73,
Don W3FPR

On 3/5/2020 5:57 PM, Rick Bates, NK7I wrote:

Don et al,

On occasion the signal that the amp goes into Operate mode is not passed 
along (or received, I don't know which), which means that the K3 will 
operate at higher than required drive level, for a moment only because 
the KPA500 will fault VERY quickly protecting everything.


However, I am unable to come up with a viable pair of suspenders, so I 
simply try to be more aware when the amp goes hot.


The reverse can be true too; the K3 thinks the amp is still in operate 
(but it isn't) and transmits at lower than expected output.



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Re: [Elecraft] Extra Protection For KPA500?

[Rick Bates, NK7I]

Don et al,

On occasion the signal that the amp goes into Operate mode is not passed 
along (or received, I don't know which), which means that the K3 will 
operate at higher than required drive level, for a moment only because 
the KPA500 will fault VERY quickly protecting everything.


However, I am unable to come up with a viable pair of suspenders, so I 
simply try to be more aware when the amp goes hot.


The reverse can be true too; the K3 thinks the amp is still in operate 
(but it isn't) and transmits at lower than expected output.


Yes, I've dis/reconnected the cables, made sure they're snugged in; it's 
not repeatable, it's random.  I do use the two cables (6') which is the 
max allowed between the K3 and KPA, which may also be part of the 
cause.  (Moving it all into a new shack over the next few days, that 
cable length will no longer be required.)


Rick NK7I

On 3/5/2020 2:38 PM, Don Wilhelm wrote:

Curiosity is getting the best of me --
If the built-in protection works well, why do you need more protection?
If the belt works OK, then why add suspenders as well?

If you are operating a K3 or K3S, there is a per band power level that 
can be used.  It will automatically use the settings for the amplifier 
when the KPA500 is set to operate.  That can be considered your 2nd 
level of protection and it guards against "fumble fingers"


73,
Don W3FPR

On 3/5/2020 2:35 PM, Tony wrote:

All:

I'd like to avoid the inevitable situation where one mistakenly 
transmits too much power into an amplifier. I have a KPA500 and the 
protection circuit works well, but I was wondering what can be done 
to add an extra layer of protection?


Tony

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Re: [Elecraft] Extra Protection For KPA500?

[Don Wilhelm]

Curiosity is getting the best of me --
If the built-in protection works well, why do you need more protection?
If the belt works OK, then why add suspenders as well?

If you are operating a K3 or K3S, there is a per band power level that 
can be used.  It will automatically use the settings for the amplifier 
when the KPA500 is set to operate.  That can be considered your 2nd 
level of protection and it guards against "fumble fingers"


73,
Don W3FPR

On 3/5/2020 2:35 PM, Tony wrote:

All:

I'd like to avoid the inevitable situation where one mistakenly 
transmits too much power into an amplifier. I have a KPA500 and the 
protection circuit works well, but I was wondering what can be done to 
add an extra layer of protection?


Tony

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[Elecraft] Extra Protection For KPA500?

[Tony]

All:

I'd like to avoid the inevitable situation where one mistakenly 
transmits too much power into an amplifier. I have a KPA500 and the 
protection circuit works well, but I was wondering what can be done to 
add an extra layer of protection?


Tony

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Re: [Elecraft] High Current only on 20 Meters

[David Gilbert]

Completely true.  According to TLW, 1,000 feet of RG-58 with a dead 
short on the far end will also have a 1:1 SWR at the near end.  Even 500 
feet will have an SWR less than 1.1:1 at the near end.


In fact, as little as 100 feet of RG-58 will turn a 2:1 SWR at the far 
end into roughly 1.5:1 at the near end even at 14 MHz.  All of the 
difference is line loss, although I'm sure someone would point out that 
it's "only" about 2.2 db worth and doesn't really change the SNR for 
receive on this end of the path (not true on the other end of course).


73,
Dave  AB7E



On 3/4/2020 11:15 PM, Jim Brown wrote:



Remember I said that VSWR in a system is set by the load (the antenna) 
and is decreased by the loss in the line. If the line is long enough 
and mismatch is great enough, the VSWR eventually ends up a 1:1. I've 
used this example as an extreme case: a 1,000 ft spool of RG58 with a 
10K ohm load would look like a perfect 50 ohm load to a transmitter at 
28 MHz, the SWR would read 1:1 at the transmitter end of the line, and 
loss in the feedline would be huge.


73, Jim K9YC


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Re: [Elecraft] K4 news?

[Eric Swartz]

Hi Irwin,

We are also concerned about the impact of the COVID-19 virus on the
shipping and supply chains we use for parts used in all of our products,
including the K4. While managing the supply chain and quickly finding
alternate parts when they go obsolete or when shortages pop up has been a
normal part of our production planning process for years, it has certainly
become more challenging as this situation quickly evolves.

We've been tracking and compensating for this on the K4 for some time.
While we manufacture our radios, amps etc. here in California, the
electronic components used by us and almost all other U.S. manufacturers
come from both the U.S. and from suppliers all around the world. (Many are
not even manufactured in the U.S.) We've been careful to source many of the
major K4 items, like the flat screen display used in the K4, from other
countries than China.  The biggest area of concern recently has been with
the passive components (resistors, caps etc) used on all of our designs.
Even when purchased from U.S. suppliers, many of these parts may come from
China and other offshore sources.

We also have built up inventory on many critical K4 parts here (including
Knobs etc.) but of course, as noted by others, it only takes a single
critical part delay in the future to hold things up.  We plan with
alternate suppliers when possible, but even then we have to periodically
scramble to source new parts for production. Fun, eh?

In any case, so far we have not encountered any major show stoppers, though
even prior to the current COVID scare began seeing delivery delays
increasing. We'll have a much better picture on how this will impact the K4
as major component deliveries arrive at the factory over the coming weeks.
Fortunately, we are busy both getting all aspects of production started and
we are also working in engineering every day to add cool new features to
the K4. Not much time to sleep at Elecraft these days.

Time for more coffee..

73,
Eric
*elecraft.com *


On Thu, Mar 5, 2020 at 5:14 AM Irwin Darack  wrote:

> I am curious to know if the reduction in manufacturing in China, do to the
> COVID-19 virus, is having an affect on the ability of Elecraft to obtain
> parts? The area of China that is the epicenter is a major manufacturer of
> electronic components.
>
> Irwin KD3TB
>
>
>
> On Wed, Mar 4, 2020 at 6:11 PM Rick Miller - N1RM  wrote:
>
> > Very clever post.
> >
> > When they announced the last delay, there was a statement that there
> would
> > be more frequent updates.  Perhaps, if nothing else, this thread will
> > provide motivation for another update.  Since many of us are "investors"
> in
> > the K4, it seems reasonable to ask.
> >
> > 73 and hope your twitter remains under control!
> > Rick
> > N1RM
> >
> >
> >
> > --
> > Sent from: http://elecraft.365791.n2.nabble.com/
> > __
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> >
> --
> Irwin KD3TB
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Re: [Elecraft] Power Factor

[Walter Underwood]

In the late 1980s, HP Labs was having wiring failures and fires in the cubicle 
wiring. Someone visited from MIT Project Athena and made a side comment about 
their wiring problems with computers at every desk. For a while, HP Labs had 
extension cords strung everywhere to reduce the demand on the wiring. Those 
went away when Steelcase replaced all the cubicle wiring with stuff that could 
handle the triplen current.

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

> On Mar 4, 2020, at 10:44 PM, Jim Brown  wrote:
> 
> On 3/4/2020 10:15 PM, Jim Brown wrote:
>> Power factor is a quantity associated with mains power (and similar power 
>> distribution systems). In the old days (when I went through EE), it was, 
>> indeed, related to the phase angle.
> 
> I meant to add that power factor now includes the triplen harmonics resulting 
> from non-sinusoidal current with power systems that are mostly electronic 
> loads. Current flows mostly in short peaks at the positive and negative peaks 
> of the mains waveform to charge the filter capacitors in the power supply; as 
> a result, the voltage waveform is rounded off and the current is rich in 
> harmonics of the mains frequency, 50 or 60 Hz.
> 
> Nearly all power distribution uses 3-phase wiring, and "triplen" harmonics 
> (those whose number is divisible by 3) add in the neutral, no matter how well 
> balanced the load between phases. This turned into a major problem roughly 50 
> years ago, when a very high fraction of current in these systems was 
> delivered to electronic loads, everything from fluorescent lights to 
> computers to anything with an AC to DC power supply. The most dangerous side 
> effect is that triplen currents in the neutral of 3-phase systems can be 
> almost twice the current in the phases, which can cause destructive failures 
> in older systems, where the neutral used conductors and hardware rated for 
> half the current in the phases! The movie "The Flaming Inferno" is based on 
> the true story of a massive fire in a high rise that was started by that 
> neutral current, spread through the building in vertical "riser" spaces, and 
> that was fueled by the insulation on the cables themselves! Sometime in the 
> last century, a
  major TV station almost went off the air because excessive heating of their 
power distribution was close to catching on fire! I attended an SBE (Society of 
Broadcast Engineers) meeting led by the consultant who worked with the station 
engineers on the problem.
> 
> MAJOR changes were made to standards for mains wiring after this event, 
> including the rating of transformers and neutral hardware to handle the peak 
> currents and the harmonic content, conduit requirements for the wiring, and 
> requirements for insulation on the wiring that does not contribute to flame 
> spread and that does not produce toxic fumes.
> 
> BTW -- the triplen harmonics also appear on equipment ground, and are the 
> reason why we mostly hear power line noise in the audio as "buzz" (triplen 
> harmonics of 50/60 Hz) rather than "hum" (pure 50/60 Hz).
> 
> There's a not-too-technical discussion of all of this written for hams in 
> http://k9yc.com/GroundingAndAudio.pdf
> and a more detailed one written for sound and video professionals in
> http://k9yc.com/SurgeXPowerGround.pdf
> 
> 73, Jim K9YC
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Re: [Elecraft] Chinese Production Re: K4 news?

[Michael Walker]

Yes, this will have a direct result in all production.

>From Elecraft's perspective, it could be a simple knob that would result in
a radio not being shipped.  It only takes 1 part since you can't ship a
radio unless it is 100.000% complete.

Mike va3mw


On Thu, Mar 5, 2020 at 8:33 AM N4ZR  wrote:

> Have you seen the incredible images of China before and after
> coronavirus, taken by a satellite specifically visualizing the amount of
> NO2 in the atmosphere
> <
> https://www.theverge.com/2020/3/2/21161324/coronavirus-quarantine-china-maps-air-pollution>.
>
> There *must* be a tremendous impact on supply chains around the world.
>
> 73, Pete N4ZR
> Check out the Reverse Beacon Network
> at , now
> spotting RTTY activity worldwide.
> For spots, please use your favorite
> "retail" DX cluster.
>
> On 3/5/2020 8:12 AM, Irwin Darack wrote:
> > I am curious to know if the reduction in manufacturing in China, do to
> the
> > COVID-19 virus, is having an affect on the ability of Elecraft to obtain
> > parts? The area of China that is the epicenter is a major manufacturer of
> > electronic components.
> >
> > Irwin KD3TB
> >
> >
> >
> > On Wed, Mar 4, 2020 at 6:11 PM Rick Miller - N1RM  wrote:
> >
> >> Very clever post.
> >>
> >> When they announced the last delay, there was a statement that there
> would
> >> be more frequent updates.  Perhaps, if nothing else, this thread will
> >> provide motivation for another update.  Since many of us are
> "investors" in
> >> the K4, it seems reasonable to ask.
> >>
> >> 73 and hope your twitter remains under control!
> >> Rick
> >> N1RM
> >>
> >>
> >>
> >> --
> >> Sent from: http://elecraft.365791.n2.nabble.com/
> >> __
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> >> Message delivered to idar...@gmail.com
> >>
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Re: [Elecraft] K4 news?

[stephen shearer]

As I wait for my K4D… I just upgraded from a K4 and added a K-Pod as the 
Easter Bunny and I decided it may not be delivered until after Easter 
(early Apr) anyway. So, I am in a planning stage.


BTW, the upgrade was easy. I sent an electronic message to Sales and 
Madelyn Gomez emailed me back and a message and a link to pay. Simple


Things seem to run slow since I retired.  It take me time to figure out 
where I "stashed" parts I know I have to do even a small project... My 
old desk mike needs connector wires re-located on the pins to fit the 
K4.  I have upgraded my headset and even purchased an adapter to work 
with my KX3 (I was going to make one).  I may just order a Heil/Kenwood 
mike cable, too.


Maybe by the time it gets here, I'll be ready...

The KX3 + amp works...


73, steve WB3LGC


On 3/3/20 6:43 PM, M. George wrote:

I guess it's been a few weeks, so it's time for a new 'Elecraft K4 / any new 
news' thread.  At least it's predictable. Give or take a few days. ;)

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Re: [Elecraft] Chinese Production Re: K4 news?

[Petr, OK1RP/M0SIS]

Lets start production in Silicon Valley again...:)
I will be proud to have genuine Made in USA rigs again.



-
73 - Petr, OK1RP 
"Apple & Elecraft freak"
B:http://ok1rp.blogspot.com
MeWe: https://bit.ly/2HGPoDx
MeWe: https://bit.ly/2FmwvDt
--
Sent from: http://elecraft.365791.n2.nabble.com/
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[Elecraft] Chinese Production Re: K4 news?

[N4ZR]

Have you seen the incredible images of China before and after 
coronavirus, taken by a satellite specifically visualizing the amount of 
NO2 in the atmosphere 
. 
There *must* be a tremendous impact on supply chains around the world.


73, Pete N4ZR
Check out the Reverse Beacon Network
at , now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

On 3/5/2020 8:12 AM, Irwin Darack wrote:

I am curious to know if the reduction in manufacturing in China, do to the
COVID-19 virus, is having an affect on the ability of Elecraft to obtain
parts? The area of China that is the epicenter is a major manufacturer of
electronic components.

Irwin KD3TB



On Wed, Mar 4, 2020 at 6:11 PM Rick Miller - N1RM  wrote:


Very clever post.

When they announced the last delay, there was a statement that there would
be more frequent updates.  Perhaps, if nothing else, this thread will
provide motivation for another update.  Since many of us are "investors" in
the K4, it seems reasonable to ask.

73 and hope your twitter remains under control!
Rick
N1RM



--
Sent from: http://elecraft.365791.n2.nabble.com/
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Re: [Elecraft] K4 news?

[Irwin Darack]

I am curious to know if the reduction in manufacturing in China, do to the
COVID-19 virus, is having an affect on the ability of Elecraft to obtain
parts? The area of China that is the epicenter is a major manufacturer of
electronic components.

Irwin KD3TB



On Wed, Mar 4, 2020 at 6:11 PM Rick Miller - N1RM  wrote:

> Very clever post.
>
> When they announced the last delay, there was a statement that there would
> be more frequent updates.  Perhaps, if nothing else, this thread will
> provide motivation for another update.  Since many of us are "investors" in
> the K4, it seems reasonable to ask.
>
> 73 and hope your twitter remains under control!
> Rick
> N1RM
>
>
>
> --
> Sent from: http://elecraft.365791.n2.nabble.com/
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-- 
Irwin KD3TB
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Re: [Elecraft] Comments from Special Forces personnel on KX2 use

[Petr, OK1RP/M0SIS]

Hi Wayne,

many thanks for that comments.

It is good to know that USSF troopers are equipped with your KX2, lol... 
I am using KX3 in backpack in similar conditions (except copter crash) and I
have to confirm that
it survived everything and works like champ. The only size and weight is
higher compare to KX2.
Maybe I should rearm to KX2 to save space in backpack and get it lighter...
Several time I thought about camo painting for my KX3...

Congrats for an excellent products and thanks for all these services Wayne.

 





-
73 - Petr, OK1RP 
"Apple & Elecraft freak"
B:http://ok1rp.blogspot.com
MeWe: https://bit.ly/2HGPoDx
MeWe: https://bit.ly/2FmwvDt
--
Sent from: http://elecraft.365791.n2.nabble.com/
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Re: [Elecraft] Power Factor

[Adrian]

Jim, Ok on that, I am a retired tradesman in the electrical industry, and
looking at why an antenna radiates best when reactance is zero leaving only
a resistance load (not taking radiation angle into account),
would seem to be because the voltage and current across the radiated load
are in phase providing maximum power dissipation, whereas any added
reactance with phase shift would diminish that ,
 as well as change the impedance.

I understand there are other factors in efficient power transfer, but I am
confident above is part of the picture. As you know it's the reason
capacitors were used in fluorescent light fittings with inductive ballasts
 for power factor correction . On my Delta loop it is great on 80m, but on
40m and up I switch in a 100pF capacitor  to null the inductive reactance I
see on the antenna there, reducing swr from 5.1:1 to 1.7:1
at the feedpoint.

It should be better, not needing that, but not all antennas follow a
resonant trend through the bands. Due to compromises etc working around
buildings and structures to do the best with what you have.

Adrian ... vk4tux

-Original Message-
From: elecraft-boun...@mailman.qth.net
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Jim Brown
Sent: Thursday, 5 March 2020 4:45 PM
To: elecraft@mailman.qth.net
Subject: [Elecraft] Power Factor

On 3/4/2020 10:15 PM, Jim Brown wrote:
> Power factor is a quantity associated with mains power (and similar 
> power distribution systems). In the old days (when I went through EE), 
> it was, indeed, related to the phase angle.

I meant to add that power factor now includes the triplen harmonics
resulting from non-sinusoidal current with power systems that are mostly
electronic loads. Current flows mostly in short peaks at the positive and
negative peaks of the mains waveform to charge the filter capacitors in the
power supply; as a result, the voltage waveform is rounded off and the
current is rich in harmonics of the mains frequency, 50 or 60 Hz.

Nearly all power distribution uses 3-phase wiring, and "triplen" 
harmonics (those whose number is divisible by 3) add in the neutral, no
matter how well balanced the load between phases. This turned into a major
problem roughly 50 years ago, when a very high fraction of current in these
systems was delivered to electronic loads, everything from fluorescent
lights to computers to anything with an AC to DC power supply. The most
dangerous side effect is that triplen currents in the neutral of 3-phase
systems can be almost twice the current in the phases, which can cause
destructive failures in older systems, where the neutral used conductors and
hardware rated for half the current in the phases! The movie "The Flaming
Inferno" is based on the true story of a massive fire in a high rise that
was started by that neutral current, spread through the building in vertical
"riser" spaces, and that was fueled by the insulation on the cables
themselves! Sometime in the last century, a major TV station almost went off
the air because excessive heating of their power distribution was close to
catching on fire! I attended an SBE (Society of Broadcast Engineers) meeting
led by the consultant who worked with the station engineers on the problem.

MAJOR changes were made to standards for mains wiring after this event,
including the rating of transformers and neutral hardware to handle the peak
currents and the harmonic content, conduit requirements for the wiring, and
requirements for insulation on the wiring that does not contribute to flame
spread and that does not produce toxic fumes.

BTW -- the triplen harmonics also appear on equipment ground, and are the
reason why we mostly hear power line noise in the audio as "buzz" 
(triplen harmonics of 50/60 Hz) rather than "hum" (pure 50/60 Hz).

There's a not-too-technical discussion of all of this written for hams in
http://k9yc.com/GroundingAndAudio.pdf
and a more detailed one written for sound and video professionals in
http://k9yc.com/SurgeXPowerGround.pdf

73, Jim K9YC
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