Re: [Elecraft] User's Dilemma

[Richard Corfield]

I thought ML serviced Elecraft in the UK. Sad that that's gone. My
experience with my KX3 was to send it to America. This was pre-Brexit, so...

It was sent to America for repair of a rotary encoder and addition of the
2m module back in 2019. This was a paperwork nightmare as I had to export
it as goods for repair, and it had to come back with the right paperwork to
connect it to my export in order that I don't pay import duties and taxes
on over £1000 worth of radio! I had to find the original receipt from the
original owner so that Elecraft on returning it could be sure to prove that
tax had been paid on the radio in the UK. The paperwork I filled in is
designed for goods export for sale, and I ended up writing on it in large
letters something like TEMPORARY EXPORT FOR REPAIR.

It came back I think without the 2m module installed (my emails to UPS are
about it having a significant part missing), though it looks like I may
have paid VAT on that (I can find a VAT bill for £85 which implies an item
cost of £425 which would be the repair, parts, 2m module and shipping

It was sent to repair in Italy for uniting with the 2m module and
calibration. We were in the EU at the time so this was easy. I imagine the
experience now we are out of the EU would be like the experience I had
sending to America.

In retrospect I've not used the 2m module that much. I'll have to get out
for more UKAC contests with it, but family is keeping me very busy at the
moment. I think the filter module would be a good purchase for my use of
the radio for CW.

The rotary encoder failed again, and I repaired it myself this time. It was
easier to risk my repair skills on a >£1000 radio than go through that
shipping/customs polava again. The original repair with Elecraft did allow
for the radio to be thoroughly checked over and any other needed updates to
be made, which was good.

 - Richard

On Fri, 15 Dec 2023 at 07:56, Doug Turnbull  wrote:

> Dear OMs,
>  The problem is that radio prices would almost certainly need to go up
> to give the dealer a margin after his/her own expenses.
>
>An independent service facility would be nice but is there adequate
> business in this?Not so sure we in EI could easily use a UK service
> facility.   I prefer to ship to California than Italy.  The cost of
> shipping to Italy may not be so wildly different than the cost of
> California freight.  Have a friend who lost a SPE 2K FA in shipping to Rome
> and received no compensation.
>
>  It is a problem for sure. I have always dealt directly with the
> factory and have been fortunate.A conundrum for sure.   Enjoy your
> Elecraft.   Be careful and pray.
>
> 73 Doug EI2CN
>
>
>
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Re: [Elecraft] KX2 Drift During Field Day

[Richard Corfield]

Are you talking about the output frequency as measured on another device?
Or the numeric readout on the radio's own display?

I've seen shifts in some situations on 2m, which I think was RF getting
into it. If you turn off Mic Up/Down button control maybe it will help
there.

I've had issues where I knocked the dial before. Oops.

 - Richard


On Mon, 29 Jun 2020 at 23:37, Ian Kahn, NV4C  wrote:

> All,
>
> I have KX2 s/n 2862. I noticed while operating Field Day that, about
> every 15 minutes, it would drift down 1 Hz. Has anyone else ever seen
> this in their KX2? I will admit it is possible this was just the effect
> of RF getting back into the rig, but at 10W, I'm not really sure where
> enough would come from to cause an issue.
>
> Thanks and 73,
>
> Ian, NV4C
>
> __
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Re: [Elecraft] USB Noise core gets hot when operating FT*?

[Richard Corfield]

You could try setting up counterpoises for the ham-stick. If it's for the
20m band, then ra few adial wires about 5m long should help. Connect to the
earth side at the base of the ham-stick. They're 1/4 wavelength so if tuned
correctly will act as a low impedance to the RF energy at the base of the
antenna providing what some call  a "virtual earth". They effectively form
the bottom half of the dipole antenna.

You'd want to protect your equipment. Another part of this equation would
be to stop RF going back down the outside of the coax to the radio. If you
don't have a choke ferrite to work with make a coil with the coax.
Inductance increases with diameter and amount of turns.

Also lower power. If you do the above then your antenna will be working
more efficiently anyway and you may find that you're doing well on 10W or
less as well as being safer. I got UK to USA on 10W on 20m this weekend
using Morse Code. Antenna was bigger which helps, though it was a dipole
who's main radiation pattern would have been more North/South (just the way
our garden is oreinted) not East/West.

 - Richard


On Tue, 21 Apr 2020 at 10:14, Richard Corfield 
wrote:

> It really sounds from the posts as if the radio and everything connected
> to it was acting as counterpoise to the ham-stick. This is dangerous
> because it means your radio is acting as part of the antenna. You don't
> want to touch antennas while they are transmitting, especially at higher
> power.
>
> The RF choke on the USB cable was doing its job to try to protect the
> computer from stray RF. If the radio is acting as part of the antenna then
> a lot of power is going to be heading down that USB cable (a
> USB-Cable-Counterpoise) and the choke will be absorbing it (or some of it)
> before it hits the computer. The choke has become hot because it's
> absorbing that RF energy. Current is flowing through it for it to get warm,
> so some energy will still be reaching the computer.
>
> It implies that a fair amount of your 50W may not be getting into the air
> at all but getting into equipment and anything touching or connected to it.
>
>  - Richard
>
>
> On Mon, 20 Apr 2020 at 20:59, Rick Bates, NK7I 
> wrote:
>
>> Jerry,
>>
>> Ignoring how you've set up your station for the moment (every station
>> has compromises but some push that to an extreme); the shutdown  of the
>> connection is likely that RF got into the USB cable (as demonstrated by
>> the hot ferrite) which caused the USB port hardware to lock up.
>>
>> USB hardware can 'stick' so it won't work properly, a complete power
>> cycle empties it of any charge, 'unsticking' the hardware.  (Yah a gross
>> simplification, but you get the point.)
>>
>> The only SURE way to restore it to function (assuming it's not blown) is
>> a complete power down (unplugged from all power, let the power supply
>> drain, disconnect the laptop battery, count another ten seconds) and
>> restart.  That is why it worked after you 'cooled it off'.
>>
>> If you can shift to a real serial port (not a serial dongle), that will
>> help.  USB is RF intolerant compared to serial.  It's simplest to avoid
>> USB as much as feasible near any RF.
>>
>> If you can't avoid USB, you'll need to add a lot more ferrite or better
>> yet, improve the antenna situation dramatically.
>>
>> In the cases I MUST run a USB connection, I distance the antenna from
>> the computer as much as possible and I run <100 watts (QRP to me), but
>> generally that's when I run a portable station.  Jim, K9YC will tell you
>> it's related to 'Pin 1' and the short version is that is has to do with
>> bonding all things to a common ground; USB devices often ignore this.
>>
>> In a few cases, improved bonding between the computer and radio /may/
>> help, but I'd have low hopes if the antenna is mere feet away.  Take the
>> hot ferrite as a warning sign, it's not a healthy environment.
>>
>> 73,
>> Rick NK7I
>>
>>
>> On 4/18/2020 5:46 PM, ae...@carolinaheli.com wrote:
>> > Today I was working a digital mode (FT8) and lost connection to the
>> radio. I
>> > cycled power with no success. On reseating the USB connection at the
>> > computer I felt the ferrite core was HOT. The cable didn't feel hot at
>> all.
>> > I'm using a 20m hamstick in the office as my antenna. I shut everything
>> down
>> > to cool off. Afterwards everything seems to be working correctly.
>> >
>> > Any ideas?
>> >
>> > Tnx and 73
>> >
>> > Jerry D. Moore
>> >
>> > AE4PB
>> >
>> > __
&g

Re: [Elecraft] USB Noise core gets hot when operating FT*?

[Richard Corfield]

It really sounds from the posts as if the radio and everything connected to
it was acting as counterpoise to the ham-stick. This is dangerous because
it means your radio is acting as part of the antenna. You don't want to
touch antennas while they are transmitting, especially at higher power.

The RF choke on the USB cable was doing its job to try to protect the
computer from stray RF. If the radio is acting as part of the antenna then
a lot of power is going to be heading down that USB cable (a
USB-Cable-Counterpoise) and the choke will be absorbing it (or some of it)
before it hits the computer. The choke has become hot because it's
absorbing that RF energy. Current is flowing through it for it to get warm,
so some energy will still be reaching the computer.

It implies that a fair amount of your 50W may not be getting into the air
at all but getting into equipment and anything touching or connected to it.

 - Richard


On Mon, 20 Apr 2020 at 20:59, Rick Bates, NK7I  wrote:

> Jerry,
>
> Ignoring how you've set up your station for the moment (every station
> has compromises but some push that to an extreme); the shutdown  of the
> connection is likely that RF got into the USB cable (as demonstrated by
> the hot ferrite) which caused the USB port hardware to lock up.
>
> USB hardware can 'stick' so it won't work properly, a complete power
> cycle empties it of any charge, 'unsticking' the hardware.  (Yah a gross
> simplification, but you get the point.)
>
> The only SURE way to restore it to function (assuming it's not blown) is
> a complete power down (unplugged from all power, let the power supply
> drain, disconnect the laptop battery, count another ten seconds) and
> restart.  That is why it worked after you 'cooled it off'.
>
> If you can shift to a real serial port (not a serial dongle), that will
> help.  USB is RF intolerant compared to serial.  It's simplest to avoid
> USB as much as feasible near any RF.
>
> If you can't avoid USB, you'll need to add a lot more ferrite or better
> yet, improve the antenna situation dramatically.
>
> In the cases I MUST run a USB connection, I distance the antenna from
> the computer as much as possible and I run <100 watts (QRP to me), but
> generally that's when I run a portable station.  Jim, K9YC will tell you
> it's related to 'Pin 1' and the short version is that is has to do with
> bonding all things to a common ground; USB devices often ignore this.
>
> In a few cases, improved bonding between the computer and radio /may/
> help, but I'd have low hopes if the antenna is mere feet away.  Take the
> hot ferrite as a warning sign, it's not a healthy environment.
>
> 73,
> Rick NK7I
>
>
> On 4/18/2020 5:46 PM, ae...@carolinaheli.com wrote:
> > Today I was working a digital mode (FT8) and lost connection to the
> radio. I
> > cycled power with no success. On reseating the USB connection at the
> > computer I felt the ferrite core was HOT. The cable didn't feel hot at
> all.
> > I'm using a 20m hamstick in the office as my antenna. I shut everything
> down
> > to cool off. Afterwards everything seems to be working correctly.
> >
> > Any ideas?
> >
> > Tnx and 73
> >
> > Jerry D. Moore
> >
> > AE4PB
> >
> > __
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:Elecraft@mailman.qth.net
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to rick.n...@gmail.com
> __
> Elecraft mailing list
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Re: [Elecraft] RF feedback into MH3 mic with KX3 on 2m

[Richard Corfield]

That didn't fix it. Found this lunchtime with a real antenna:

   - Worked OK with case open, testing the idea it was coupling from the 2m
   module itself.
   - Worked on other mic (SoundMagic earbuds and mic)
   - Touching the case with metal made interesting noises on receive.
   - HF (20m) seemed OK, if I take the response "America only please" as
   indicative the other station heard me and my signal was good enough for him
   to tell I was not in America.

 - Richard

On Wed, 5 Feb 2020 at 22:07, Richard Corfield 
wrote:

> The metal shield cover on the 2m module was not flat but slightly raised
> at the edge. I have pressed this back on and the problem seems cleared. So
> I guess it was contacting or coming close to the circuit board on the
> control module, perhaps that giving the feedback loop for RF. Question is -
> could any damage have done if it had contacted the vias/pads on the board
> there?
>
>  - Richard
>
> On Wed, 5 Feb 2020 at 21:01, Richard Corfield 
> wrote:
>
>> I've done some further tests and proven the problem is with the MH3. So
>> I'll have to take that apart and look for the problem.
>> The radio is fine with little earbuds/mic plugged in via splitter cable.
>> Swap out the mic on the earbuds with the MH3 and leave all the rest the
>> same and it goes wrong.
>>
>>  Thanks
>>  - Richard
>>
>> On Wed, 5 Feb 2020 at 15:29, Nr4c  wrote:
>>
>>> Turn down TX Monitor volume.
>>>
>>> Sent from my iPhone
>>> ...nr4c. bill
>>>
>>>
>>> > On Feb 5, 2020, at 5:23 AM, Richard Corfield <
>>> richard.corfi...@gmail.com> wrote:
>>> >
>>> > I had issues with RF feedback on the MH3 during the UKAC SSB 2m
>>> contest
>>> > last night. It seemed intermittent. Result was terrible noise in
>>> Monitor
>>> > output (my headphones) and to the other station, so it affects the
>>> audio
>>> > input. With experiments at the time and this morning:
>>> >
>>> >
>>> >   - Occurs when RF power is increased above 0 and when Mic Gain is
>>> >   increased. I could operate with Mic Gain set low, obviously at
>>> reduced
>>> >   power out. (Indicative of a feedback loop)
>>> >   - Occurs with a dummy load. (Also when I moved the antenna away last
>>> >   night). So is the loop internal or is it so sensitive the small leak
>>> from a
>>> >   dummy load is enough?
>>> >   - Does not occur if I feed a stage Mic In through a field mixer (kit
>>> I
>>> >   have to hand). The field mixer claims an output impedance of 150R
>>> and is
>>> >   running at mic level to match the MH3 allowing same gain setup in
>>> the KX3.
>>> >   Mic Bias is turned off in this case.
>>> >   - Does not occur on HF into the dummy load.
>>> >   - Manifests as buzzing on 2m FM
>>> >   - May result in phantom button presses on the KX3 Mic (I didn't
>>> think I
>>> >   knocked the dial)
>>> >
>>> > As an aside - one station last night was loud enough to activate the
>>> "RX"
>>> > indicator which I take to be input overload. S meter was well over S9
>>> but
>>> > not at the top. I didn't see anyone else at the site, unless they were
>>> > hiding the the woodland carpark but I saw no light there or on the
>>> summit
>>> > behind me. I hit ATT, should have swung the beam to try to null them.
>>> But I
>>> > guess the ATT and even maybe the input protection is after the 2m
>>> module's
>>> > input?
>>> >
>>> > My thought is I need to inspect the wiring in the mic. Or could there
>>> be
>>> > anything else I need to check?
>>> >
>>> > Thanks
>>> >  - Richard
>>> > __
>>> > Elecraft mailing list
>>> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> > Help: http://mailman.qth.net/mmfaq.htm
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>>> >
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>>> > Message delivered to n...@widomaker.com
>>>
>>>
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Re: [Elecraft] RF feedback into MH3 mic with KX3 on 2m

[Richard Corfield]

The metal shield cover on the 2m module was not flat but slightly raised at
the edge. I have pressed this back on and the problem seems cleared. So I
guess it was contacting or coming close to the circuit board on the control
module, perhaps that giving the feedback loop for RF. Question is - could
any damage have done if it had contacted the vias/pads on the board there?

 - Richard

On Wed, 5 Feb 2020 at 21:01, Richard Corfield 
wrote:

> I've done some further tests and proven the problem is with the MH3. So
> I'll have to take that apart and look for the problem.
> The radio is fine with little earbuds/mic plugged in via splitter cable.
> Swap out the mic on the earbuds with the MH3 and leave all the rest the
> same and it goes wrong.
>
>  Thanks
>  - Richard
>
> On Wed, 5 Feb 2020 at 15:29, Nr4c  wrote:
>
>> Turn down TX Monitor volume.
>>
>> Sent from my iPhone
>> ...nr4c. bill
>>
>>
>> > On Feb 5, 2020, at 5:23 AM, Richard Corfield <
>> richard.corfi...@gmail.com> wrote:
>> >
>> > I had issues with RF feedback on the MH3 during the UKAC SSB 2m contest
>> > last night. It seemed intermittent. Result was terrible noise in Monitor
>> > output (my headphones) and to the other station, so it affects the audio
>> > input. With experiments at the time and this morning:
>> >
>> >
>> >   - Occurs when RF power is increased above 0 and when Mic Gain is
>> >   increased. I could operate with Mic Gain set low, obviously at reduced
>> >   power out. (Indicative of a feedback loop)
>> >   - Occurs with a dummy load. (Also when I moved the antenna away last
>> >   night). So is the loop internal or is it so sensitive the small leak
>> from a
>> >   dummy load is enough?
>> >   - Does not occur if I feed a stage Mic In through a field mixer (kit I
>> >   have to hand). The field mixer claims an output impedance of 150R and
>> is
>> >   running at mic level to match the MH3 allowing same gain setup in the
>> KX3.
>> >   Mic Bias is turned off in this case.
>> >   - Does not occur on HF into the dummy load.
>> >   - Manifests as buzzing on 2m FM
>> >   - May result in phantom button presses on the KX3 Mic (I didn't think
>> I
>> >   knocked the dial)
>> >
>> > As an aside - one station last night was loud enough to activate the
>> "RX"
>> > indicator which I take to be input overload. S meter was well over S9
>> but
>> > not at the top. I didn't see anyone else at the site, unless they were
>> > hiding the the woodland carpark but I saw no light there or on the
>> summit
>> > behind me. I hit ATT, should have swung the beam to try to null them.
>> But I
>> > guess the ATT and even maybe the input protection is after the 2m
>> module's
>> > input?
>> >
>> > My thought is I need to inspect the wiring in the mic. Or could there be
>> > anything else I need to check?
>> >
>> > Thanks
>> >  - Richard
>> > __
>> > Elecraft mailing list
>> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> > Help: http://mailman.qth.net/mmfaq.htm
>> > Post: mailto:Elecraft@mailman.qth.net
>> >
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>> > Message delivered to n...@widomaker.com
>>
>>
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Re: [Elecraft] RF feedback into MH3 mic with KX3 on 2m

[Richard Corfield]

I've done some further tests and proven the problem is with the MH3. So
I'll have to take that apart and look for the problem.
The radio is fine with little earbuds/mic plugged in via splitter cable.
Swap out the mic on the earbuds with the MH3 and leave all the rest the
same and it goes wrong.

 Thanks
 - Richard

On Wed, 5 Feb 2020 at 15:29, Nr4c  wrote:

> Turn down TX Monitor volume.
>
> Sent from my iPhone
> ...nr4c. bill
>
>
> > On Feb 5, 2020, at 5:23 AM, Richard Corfield 
> wrote:
> >
> > I had issues with RF feedback on the MH3 during the UKAC SSB 2m contest
> > last night. It seemed intermittent. Result was terrible noise in Monitor
> > output (my headphones) and to the other station, so it affects the audio
> > input. With experiments at the time and this morning:
> >
> >
> >   - Occurs when RF power is increased above 0 and when Mic Gain is
> >   increased. I could operate with Mic Gain set low, obviously at reduced
> >   power out. (Indicative of a feedback loop)
> >   - Occurs with a dummy load. (Also when I moved the antenna away last
> >   night). So is the loop internal or is it so sensitive the small leak
> from a
> >   dummy load is enough?
> >   - Does not occur if I feed a stage Mic In through a field mixer (kit I
> >   have to hand). The field mixer claims an output impedance of 150R and
> is
> >   running at mic level to match the MH3 allowing same gain setup in the
> KX3.
> >   Mic Bias is turned off in this case.
> >   - Does not occur on HF into the dummy load.
> >   - Manifests as buzzing on 2m FM
> >   - May result in phantom button presses on the KX3 Mic (I didn't think I
> >   knocked the dial)
> >
> > As an aside - one station last night was loud enough to activate the "RX"
> > indicator which I take to be input overload. S meter was well over S9 but
> > not at the top. I didn't see anyone else at the site, unless they were
> > hiding the the woodland carpark but I saw no light there or on the summit
> > behind me. I hit ATT, should have swung the beam to try to null them.
> But I
> > guess the ATT and even maybe the input protection is after the 2m
> module's
> > input?
> >
> > My thought is I need to inspect the wiring in the mic. Or could there be
> > anything else I need to check?
> >
> > Thanks
> >  - Richard
> > __
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:Elecraft@mailman.qth.net
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to n...@widomaker.com
>
>
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Re: [Elecraft] RF feedback into MH3 mic with KX3 on 2m

[Richard Corfield]

Even with monitor running into headphones?

I was running the contest with monitor off at first, but I turned monitor
on only in response to my contact telling me my audio was garbled. That
said, I initially wondered if the garble was due to frequency drift not
feedback. Though if it was a monitor problem it would also manifest on HF
and through the vocal mic?

I can try though. I know the headphones leak, closed as they are, as I've
picked up notification beeps when using the field recorder and monitoring
on headphones while recording my voice.

 - Richard


On Wed, 5 Feb 2020 at 15:29, Nr4c  wrote:

> Turn down TX Monitor volume.
>
> Sent from my iPhone
> ...nr4c. bill
>
>
> > On Feb 5, 2020, at 5:23 AM, Richard Corfield 
> wrote:
> >
> > I had issues with RF feedback on the MH3 during the UKAC SSB 2m contest
> > last night. It seemed intermittent. Result was terrible noise in Monitor
> > output (my headphones) and to the other station, so it affects the audio
> > input. With experiments at the time and this morning:
> >
> >
> >   - Occurs when RF power is increased above 0 and when Mic Gain is
> >   increased. I could operate with Mic Gain set low, obviously at reduced
> >   power out. (Indicative of a feedback loop)
> >   - Occurs with a dummy load. (Also when I moved the antenna away last
> >   night). So is the loop internal or is it so sensitive the small leak
> from a
> >   dummy load is enough?
> >   - Does not occur if I feed a stage Mic In through a field mixer (kit I
> >   have to hand). The field mixer claims an output impedance of 150R and
> is
> >   running at mic level to match the MH3 allowing same gain setup in the
> KX3.
> >   Mic Bias is turned off in this case.
> >   - Does not occur on HF into the dummy load.
> >   - Manifests as buzzing on 2m FM
> >   - May result in phantom button presses on the KX3 Mic (I didn't think I
> >   knocked the dial)
> >
> > As an aside - one station last night was loud enough to activate the "RX"
> > indicator which I take to be input overload. S meter was well over S9 but
> > not at the top. I didn't see anyone else at the site, unless they were
> > hiding the the woodland carpark but I saw no light there or on the summit
> > behind me. I hit ATT, should have swung the beam to try to null them.
> But I
> > guess the ATT and even maybe the input protection is after the 2m
> module's
> > input?
> >
> > My thought is I need to inspect the wiring in the mic. Or could there be
> > anything else I need to check?
> >
> > Thanks
> >  - Richard
> > __
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[Elecraft] RF feedback into MH3 mic with KX3 on 2m

[Richard Corfield]

I had issues with RF feedback on the MH3 during the UKAC SSB 2m contest
last night. It seemed intermittent. Result was terrible noise in Monitor
output (my headphones) and to the other station, so it affects the audio
input. With experiments at the time and this morning:


   - Occurs when RF power is increased above 0 and when Mic Gain is
   increased. I could operate with Mic Gain set low, obviously at reduced
   power out. (Indicative of a feedback loop)
   - Occurs with a dummy load. (Also when I moved the antenna away last
   night). So is the loop internal or is it so sensitive the small leak from a
   dummy load is enough?
   - Does not occur if I feed a stage Mic In through a field mixer (kit I
   have to hand). The field mixer claims an output impedance of 150R and is
   running at mic level to match the MH3 allowing same gain setup in the KX3.
   Mic Bias is turned off in this case.
   - Does not occur on HF into the dummy load.
   - Manifests as buzzing on 2m FM
   - May result in phantom button presses on the KX3 Mic (I didn't think I
   knocked the dial)

As an aside - one station last night was loud enough to activate the "RX"
indicator which I take to be input overload. S meter was well over S9 but
not at the top. I didn't see anyone else at the site, unless they were
hiding the the woodland carpark but I saw no light there or on the summit
behind me. I hit ATT, should have swung the beam to try to null them. But I
guess the ATT and even maybe the input protection is after the 2m module's
input?

My thought is I need to inspect the wiring in the mic. Or could there be
anything else I need to check?

Thanks
  - Richard
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Re: [Elecraft] Center-fed antennas

[Richard Corfield]

I don't do field day. I've been using monoband dipoles so far for portable
operations due to cost and weight constraints. They work incredibly well,
and I hope to go out with a high Q antenna for 30m and a long pole to try
end fed vertical. (My long pole seems stuck in the post! Courier emailed.).
That said, an antenna which really should be 30m only due to its resonant
matching circuit can be operated on neighbouring bands using the KX3's
tuner. I've had contacts over reasonable distance on 40m with it.

The multiband antennae seem attractive for things like SOTA and single
station operation. At the moment I need to drop my antenna and change links
around to change band. It doesn't take too long to be fair. I'll experiment
with a multiband off centre fed antenna which, even if it ends up too heavy
to carry up a mountain, could make a useful home station antenna. At the
moment my portable setup is set up in the garden but I wonder how well the
home made antenna will stand up to our increasingly winter weather.

 - Richard


On Fri, 11 Oct 2019 at 00:57, Al Lorona  wrote:

> Fair enough, but it kinda goes without saying that in a group FD with 1
> station per band they'll use resonant, single-band antennas. If this is our
> best argument against the 'multiband dipole', then that antenna still holds
> its own pretty well in a multitude of other situations.
>
> I have always found a deep resistance and opposition to this antenna.
> Whether it's an unwillingness to use antenna tuners, which many hams have,
> or an undue fear of noise, which some hams have, or a belief that open-wire
> line is noisier/weirder/harder/impossible-to-go-through-walls, which many
> hams believe, the visceral reaction against this antenna always amazes and
> baffles me.
>
> Please forgive my belligerence... the Dodgers lost and I've been in a sour
> mood all day.
>
> Al  W6LX
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Re: [Elecraft] ALC implementation

[Richard Corfield]

The compression modulates the signal. That will have a fourier transform of
its own. If we think of it as a simple amplitude modulation then, as for AM
signals, the spectrum of the original signal will be combined (convolved)
with upper and lower sidebands representing the spectrum of the compressor.
Our ears don't notice (unless we're sound guys listening to a pop song
thinking "They've squashed those dynamics to death" ;-) ) but maybe a
digital mode will.

The transmitted signal is constrained to the IF passband so you stay within
band. The compression frequencies and hopefully amplitude are both small so
the artefacts it introduces into the spectrum should also be both narrow
and small.

 - Richard


On Fri, 12 Jul 2019 at 22:01, Wes  wrote:

> What distortion?
>
> On 7/12/2019 1:15 PM, Jim Rhodes wrote:
> > Nothing when it is done correctly on a mode that can stand the
> distortion. I
> > personally won't use it on digital modes as my rigs tend to turn it off
> by
> > default.
> >
> > Jim Rhodes
> > K0XU
> >
> > On Fri, Jul 12, 2019, 15:10 Wes  > > wrote:
> >
> > And what exactly is the problem with compression?  It's used all
> over the
> > place.
> >
> > Wes  N7WS
> >
> > On 6/28/2019 11:38 AM, Brian Denley wrote:
> > > I have always thought that ALC is not appropriate for power
> control.
> > It’s a protection system.  Over use of ALC acts like compression.
> No?
> > >
> > > Brian
> > > KB1VBF
> > > Sent from my iPad
> >
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> >
>
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Re: [Elecraft] ALC implementation

[Richard Corfield]

That's interesting thanks. It means that by aiming for no ALC indication
I've been under modulating.

I assume the input stage in the KX3 can take higher levels?

On Fri, 28 Jun 2019, 16:35 Bob McGraw K4TAX,  wrote:

> Well written generic paper for operation of FT-8 and other digital
> signals of like mode.   It does not totally nor correctly apply to
> Elecraft radios as power management is handled by a totally different
> means.   And those means and methods suggested in this paper are not
> applicable to Elecraft radios for power control.   From experience in
> set-up and operating different radios and different interfaces, I do
> believe that the WSJT-X operating panel which shows the right slider
> labeled PWR is very misleading and should be changed to some other
> description i.e. TX AUD.
>
> While many radios use the control of audio level to adjust power output,
> this is somewhat misleading as there are control areas available such as
> SPKR level in Windows, and Line Gain for the radios or perhaps an
> external sound card device.   Again, the use of the acronym MIC is
> always a frighting term,  in as much as many systems produce a transmit
> audio level that will overdrive the microphone pre-amplifier input.
> Once this occurs, reducing MIC gain will not relieve the distorted audio
> as it occurs pre level control in the circuit.   Frankly, one should not
> connect the sound card to a microphone input without proper and correct
> means of attenuating the signal before it is connected to the microphone
> input.   In addition, this will always preserve the transmit
> Signal-to-Noise ratio.
>
> As to "compression" I take that to mean Speech Processing, which should
> ALWAYS be off or set to a zero value.   Likewise for EQ, again always
> set to OFF or FLAT  for transmit and receive purposes as well.
>
> As a mater of practice, there are three or perhaps four distinct places
> that audio levels can be controlled in the transmit path. First is SPKR
> level which is the audio level out of the computer. Second is the WSJT-X
> PWR slider, and third is the Line Gain within the radio.  A fourth, if
> used, would be an external interface such as a Signalink or
> Soundblaster.   If any of these points end up near minimum value or near
> maximum value, I strongly suggest further investigation as to why and
> remedial steps taken to more "normalize" the control values at all
> points in the system.
>
> Some radios do have "meter" indicators which relate to ALC levels while
> others simply prove a visual means usually the illumination of a LED.
> In all cases, the indicators should be observed, and the radio operated
> accordingly with NO indicated ALC action occurring.Again, regarding
> Elecraft radios, the first 4 bars on the "ALC Scale" are audio level and
> NOT ALC action.  The onset of actual ALC occurs at the 5th bar and higher.
>
> 73
>
> Bob, K4TAX
>
>
>
>
> On 6/28/2019 9:18 AM, Andy Durbin wrote:
> > Does anyone know of any rig that uses "compression" rather than linear
> gain control to implement ALC?
> >
> > ref - https://www.dropbox.com/s/f4uaop5tqwzaweu/FT8Noise6.docx?dl=1
> >
> > 73,
> > Andy, k3wyc
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Re: [Elecraft] Sending KX3 to Elecraft for repair from Canada

[Richard Corfield]

Did you pay VAT on the repair?

On Fri, 28 Jun 2019, 19:08 Roger Stein,  wrote:

> Brian,
> I used Canada Post to send my K3 #75 in for repair. Elecraft used USPS for
> return. Documents were marked “for repair”. No hassle, no brokerage fees,
> just return shipping fees. Tracked package online going and return. Worked
> just fine. All the best.
> 73, Roger VA1RST Halifax
>
> Sent from my iPhone
>
> > On Jun 28, 2019, at 1:02 PM, Richard Corfield <
> richard.corfi...@gmail.com> wrote:
> >
> > I used UPS and need to write up my experience. Your question will
> encourage
> > that!
> >
> > I found that UPS's Customs Forms generator produced a Sales Invoice even
> > though I asked it to produce a Temporary Export for Repair. So I crossed
> > out the Sales part and wrote in pen that this was a repair and will be
> > returned.
> >
> > My parcel has been received and neither Elecraft or UPS have informed me
> of
> > any charges. Though an email from US Border Control when I've just
> received
> > in response to my question talks about Bonds. I may have been lucky that
> > the HSS Code for radio transceivers is duty free as the bond is about
> duty
> > which does not apply (at least from friendly countries according to the
> US
> > Border Control web site)
> >
> > An impression I got is that nobody can predict, or will stand by a
> > prediction, about what Customs will do. UK Customs helpline advised me to
> > state "FOR REPAIR" on the outgoing forms and "BRITISH GOODS RETURNED
> AFTER
> > REPAIR" on the return (or something like that). In the end someone at
> UPS I
> > think it was said that putting "Export Reason: Repair" on their form
> should
> > do it. Elecraft note that they have experience of how to handle the
> return,
> > and I've included a copy of the radio's sales receipt as suggested so if
> > needed I can prove that UK VAT has been paid already when it comes to
> > re-importing it.
> >
> > So I've been successful. I can say that what I did was quite simple in
> the
> > end, but I only _think_ I understand the procedure.
> >
> > - Richard
> >
> >
> > On Fri, 28 Jun 2019 at 16:49, Brian “VE3BWP” Pietrzyk 
> > wrote:
> >
> >> I’m hoping to hear from any Canadian HAMs who have successfully sent
> their
> >> radio (KX3 in my case) to Elecraft USA for repair and got it back with
> the
> >> least amount of brokerage hassles.
> >>
> >> Which carrier did you use? How did it go?
> >>
> >> I ask because I once had to send a Yaesu in for a warranty repair from
> >> near Toronto to California. Yaesu asked I use Fedex and it was a
> nightmare.
> >> Hoping to avoid that again.
> >>
> >> Thanks,
> >>
> >> Brian ve3bwp.
> >> __
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Re: [Elecraft] Sending KX3 to Elecraft for repair from Canada

[Richard Corfield]

You'd think they'd include the predictable fees in the price to the sender.
It will be really bad if they charged the recipient, especially if the
parcel went through customs ok.

On Fri, 28 Jun 2019, 19:35 Don Wilhelm,  wrote:

> Brian,
>
> Use the postal system.  There are no "brokerage fees" charged by the
> postal system.  UPS and FedEX do charge "brokerage fees"  Customs is a
> different matter - usually properly marked customs forms will go through
> with no problem.
>
> 73,
> Don W3FPR
>
> On 6/28/2019 11:48 AM, Brian “VE3BWP” Pietrzyk wrote:
> > I’m hoping to hear from any Canadian HAMs who have successfully sent
> their radio (KX3 in my case) to Elecraft USA for repair and got it back
> with the least amount of brokerage hassles.
> >
> > Which carrier did you use? How did it go?
> >
> > I ask because I once had to send a Yaesu in for a warranty repair from
> near Toronto to California. Yaesu asked I use Fedex and it was a nightmare.
> Hoping to avoid that again.
> >
> > Thanks,
> >
> > Brian ve3bwp.
> > __
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> >
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Re: [Elecraft] Sending KX3 to Elecraft for repair from Canada

[Richard Corfield]

I used UPS and need to write up my experience. Your question will encourage
that!

I found that UPS's Customs Forms generator produced a Sales Invoice even
though I asked it to produce a Temporary Export for Repair. So I crossed
out the Sales part and wrote in pen that this was a repair and will be
returned.

My parcel has been received and neither Elecraft or UPS have informed me of
any charges. Though an email from US Border Control when I've just received
in response to my question talks about Bonds. I may have been lucky that
the HSS Code for radio transceivers is duty free as the bond is about duty
which does not apply (at least from friendly countries according to the US
Border Control web site)

An impression I got is that nobody can predict, or will stand by a
prediction, about what Customs will do. UK Customs helpline advised me to
state "FOR REPAIR" on the outgoing forms and "BRITISH GOODS RETURNED AFTER
REPAIR" on the return (or something like that). In the end someone at UPS I
think it was said that putting "Export Reason: Repair" on their form should
do it. Elecraft note that they have experience of how to handle the return,
and I've included a copy of the radio's sales receipt as suggested so if
needed I can prove that UK VAT has been paid already when it comes to
re-importing it.

So I've been successful. I can say that what I did was quite simple in the
end, but I only _think_ I understand the procedure.

 - Richard


On Fri, 28 Jun 2019 at 16:49, Brian “VE3BWP” Pietrzyk 
wrote:

> I’m hoping to hear from any Canadian HAMs who have successfully sent their
> radio (KX3 in my case) to Elecraft USA for repair and got it back with the
> least amount of brokerage hassles.
>
> Which carrier did you use? How did it go?
>
> I ask because I once had to send a Yaesu in for a warranty repair from
> near Toronto to California. Yaesu asked I use Fedex and it was a nightmare.
> Hoping to avoid that again.
>
> Thanks,
>
> Brian ve3bwp.
> __
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Re: [Elecraft] Left hand rotary encoder failure on KX3

[Richard Corfield]

Serial number is 8383, if that helps place the manufacturing date and
therefore whether it's part of a batch with a known issue?

 - Richard

On Thu, 13 Jun 2019 at 08:03, Richard Corfield 
wrote:

> I've tried that with no success. Though I'd have been surprised as the
> trace labelling on the connector indicate microcontroller serial data
> rather than individual switches. I'd expect the switch handling to be done
> on the switch board.
>
> I have SotaBeam's powerpole adapter fitted to the power connector which
> has a slightly longer screw. Could that affect things? Looking behind the
> panel I'd think not as there's just space between the switch rubber there.
> I plugged a remote speaker into the headphone jack, but a 3.5mm stereo plug
> is a 3.5mm stereo plug and I'd not expect that to damage things either.
>
>  - Richard
>
> On Wed, 12 Jun 2019 at 23:53, Bill Frantz  wrote:
>
>> On 6/12/19 at 2:52 PM, richard.corfi...@gmail.com (Richard
>> Corfield) wrote:
>>
>> >I've tried my KX3 today and noticed that the left hand volume rotary
>> >encoder is not working. Is this a common problem? Is there anything I can
>> >do to try to get it working again?
>> >
>> >I'm in the UK and this is a second hand radio, so I can't so easily just
>> >sent it back to Elecraft I don't think.
>> >
>> >A firmware restore has given me a non-zero AF Gain setting, but no
>> sidetone
>> >as that is turned low and can't change without this encoder.
>>
>> Sometimes control buttons fail to work due to the ribbon cable
>> connecting the two halves of the KX3 becoming loose or
>> developing bad connections. Opening the KX3 and
>> unplugging/replugging the cable at both ends frequently fixes
>> this class of problem. Using a contact cleaner on the cable
>> contacts may also help.
>>
>> 73 Bill AE6JV
>>
>> -
>> Bill Frantz| When it comes to the world | Periwinkle
>> (408)356-8506  | around us, is there any choice | 16345
>> Englewood Ave
>> www.pwpconsult.com | but to explore? - Lisa Randall | Los Gatos,
>> CA 95032
>>
>>
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Re: [Elecraft] Left hand rotary encoder failure on KX3

[Richard Corfield]

I've tried that with no success. Though I'd have been surprised as the
trace labelling on the connector indicate microcontroller serial data
rather than individual switches. I'd expect the switch handling to be done
on the switch board.

I have SotaBeam's powerpole adapter fitted to the power connector which has
a slightly longer screw. Could that affect things? Looking behind the panel
I'd think not as there's just space between the switch rubber there. I
plugged a remote speaker into the headphone jack, but a 3.5mm stereo plug
is a 3.5mm stereo plug and I'd not expect that to damage things either.

 - Richard

On Wed, 12 Jun 2019 at 23:53, Bill Frantz  wrote:

> On 6/12/19 at 2:52 PM, richard.corfi...@gmail.com (Richard
> Corfield) wrote:
>
> >I've tried my KX3 today and noticed that the left hand volume rotary
> >encoder is not working. Is this a common problem? Is there anything I can
> >do to try to get it working again?
> >
> >I'm in the UK and this is a second hand radio, so I can't so easily just
> >sent it back to Elecraft I don't think.
> >
> >A firmware restore has given me a non-zero AF Gain setting, but no
> sidetone
> >as that is turned low and can't change without this encoder.
>
> Sometimes control buttons fail to work due to the ribbon cable
> connecting the two halves of the KX3 becoming loose or
> developing bad connections. Opening the KX3 and
> unplugging/replugging the cable at both ends frequently fixes
> this class of problem. Using a contact cleaner on the cable
> contacts may also help.
>
> 73 Bill AE6JV
>
> -
> Bill Frantz| When it comes to the world | Periwinkle
> (408)356-8506  | around us, is there any choice | 16345
> Englewood Ave
> www.pwpconsult.com | but to explore? - Lisa Randall | Los Gatos,
> CA 95032
>
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[Elecraft] Left hand rotary encoder failure on KX3

[Richard Corfield]

I've tried my KX3 today and noticed that the left hand volume rotary
encoder is not working. Is this a common problem? Is there anything I can
do to try to get it working again?

I'm in the UK and this is a second hand radio, so I can't so easily just
sent it back to Elecraft I don't think.

A firmware restore has given me a non-zero AF Gain setting, but no sidetone
as that is turned low and can't change without this encoder.

Thanks

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

[Richard Corfield]

Which is interesting. We were taught that you can recover signals up to the
Nyquist frequency (half sampling frequency) before aliasing becomes an
issue. People low pass filter well before then to avoid aliasing issues,
but it means you need a sampling frequency sufficiently more than twice the
highest frequency you want to record. So presumably for the 6m band that's
sufficiently greater than 110,000,000 samples per second.

What gets me though, is when you look at the waveforms and the sampling
waveforms, a signal at the Nyquist frequency could have magnitude from 0 to
full size depending on its phase with respect to the sampling. Assuming
regular sampling (do any dither the sampling?). Move just below Nyquist and
you'll see a beat frequency come in as it moves in and out of phase. I
guess the maths is based on infinite time - Fourier being the integral from
-infinity to +infinity - but we've not got infinite time to listen to an
infinitely long SSB signal.

You can buy a reasonably cheap digital oscilloscope (Tektronix TBS1000 -
£600) which boasts 1GS/s so a Nyquist frequency of 500MHz. They claim 50MHz
analogue bandwidth.  (If you're thinking of buying this double check the
figures first rather than take my work for it. The marketing material was a
little opaque).

A 2nd order filter (cheap, simple) with a 3dB point at 50MHz and
40dB/decade would be about 40dB down by the Nyquist frequency. In the lower
bands, say 10MHz, the first aliases are from 990MHz which is 55dB down if I
remember my maths right. I'd assume someone would use better than a 2nd
order filter or a faster sampling ADC.



On Thu, 6 Jun 2019 at 10:38, David Woolley 
wrote:

> On 05/06/2019 13:23, W2xj wrote:
> > Direct sampling has no image issues.
>
> That's because they are called aliasing issues!
>
> --
> David Woolley
>
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Re: [Elecraft] K4: superhet vs. direct sampling

[Richard Corfield]

I was getting confused momentarily with Direct Conversion :-)

On Wed, 5 Jun 2019 at 13:23, W2xj  wrote:

> Direct sampling has no image issues.
>
> Sent from my iPad
>
> > On Jun 5, 2019, at 3:23 AM, Richard Corfield 
> wrote:
> >
> > I'd have thought that superhet would always have the advantage of
> improved
> > image rejection due to the IF band filtering. It would also allow ADCs
> and
> > associated processing to run slower or lower down in relation to its
> > Nyquist frequency so allowing for more detail in the sampled signal. Also
> > can narrow band analogue filtering beat the dynamic range of the ADC? If
> > its top 10 bits are taken up handling that huge strong signal in its
> input
> > passband then you've got fewer bits left for your signal of interest. So
> > both high bit depth and high sample rate in comparison to signal are
> harder
> > to achieve.
> >
> > The opposing view being the cost of achieving a high quality Superhet
> > conversion? If direct sampling and high speed signal processing (FPGA?)
> can
> > achieve the results so much more cheaply and simply and reliably? Like
> the
> > Class D amplifier in reverse.
> >
> > - Richard (M0RJC)
> >
> >
> >> On Wed, 5 Jun 2019 at 03:19, Wayne Burdick  wrote:
> >>
> >> The superhet module buys a lot of BDR improvement. But also -- a
> subtlety
> >> I've failed to mention so far -- the superhet module is intended to
> >> somewhat improve 2 kHz IMDDR3 *and* make this figure more repeatable.
> >>
> >> Q: Say what?
> >>
> >> A: As Rob Sherwood noted many times before finally immortalizing this
> >> point in his must-read footnotes, A-to-D converters sharing the same
> part
> >> number are not all created equal. The long-time previous occupant of his
> >> Top Spot benefitted from a never-corroborated monotonicity in its ADC's
> >> LSBs. An act of god. The product of a very good day at the silicon
> foundry
> >> when, serendipitously, all the bunny suits were defect-free, and no one
> was
> >> exhaling molecules of grain alcohol or other substances from the night
> >> before.
> >>
> >> That said, most ops can get by without the extra BDR and IMDDR3, because
> >> they're not situated in the RF equivalent of the Gulf Stream. Hence the
> >> different K4 models.
> >>
> >> 73,
> >
>
>
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Re: [Elecraft] K4: superhet vs. direct sampling

[Richard Corfield]

I'd have thought that superhet would always have the advantage of improved
image rejection due to the IF band filtering. It would also allow ADCs and
associated processing to run slower or lower down in relation to its
Nyquist frequency so allowing for more detail in the sampled signal. Also
can narrow band analogue filtering beat the dynamic range of the ADC? If
its top 10 bits are taken up handling that huge strong signal in its input
passband then you've got fewer bits left for your signal of interest. So
both high bit depth and high sample rate in comparison to signal are harder
to achieve.

The opposing view being the cost of achieving a high quality Superhet
conversion? If direct sampling and high speed signal processing (FPGA?) can
achieve the results so much more cheaply and simply and reliably? Like the
Class D amplifier in reverse.

 - Richard (M0RJC)


On Wed, 5 Jun 2019 at 03:19, Wayne Burdick  wrote:

> The superhet module buys a lot of BDR improvement. But also -- a subtlety
> I've failed to mention so far -- the superhet module is intended to
> somewhat improve 2 kHz IMDDR3 *and* make this figure more repeatable.
>
> Q: Say what?
>
> A: As Rob Sherwood noted many times before finally immortalizing this
> point in his must-read footnotes, A-to-D converters sharing the same part
> number are not all created equal. The long-time previous occupant of his
> Top Spot benefitted from a never-corroborated monotonicity in its ADC's
> LSBs. An act of god. The product of a very good day at the silicon foundry
> when, serendipitously, all the bunny suits were defect-free, and no one was
> exhaling molecules of grain alcohol or other substances from the night
> before.
>
> That said, most ops can get by without the extra BDR and IMDDR3, because
> they're not situated in the RF equivalent of the Gulf Stream. Hence the
> different K4 models.
>
> 73,
> Wayne
> N6KR
>
>
> > On Jun 4, 2019, at 5:10 PM, Lyle Johnson  wrote:
> >
> > Mark,
> >
> > The "20 dB lower than a K3" figure is an estimate for 100 kHz Blocking
> Dynamic Range rather than the 2 kHz Narrow Spaced Dynamic Range.
> >
> > The K3 is listed at 140 to 150 dB (depending on model, synthesizer, etc)
> on Sherwood's Receiver Test Data page.  The K4 series without the "HD"
> option are estimated to be in the 120 to 130 dB range, typical of other
> direct sampling SDR products (Flex, Apache, Icom, ...).
> >
> > 73,
> >
> > Lyle KK7P
> >
> > On 6/4/19 4:00 PM, mark roz via Elecraft wrote:
> >> Before putting my money up front for the first run of K4D I need to
> know what is the dynamic range
> >> of the K4D RX at 2kHz spacing. K3 is 105 dB and K4D? If it is 20dB
> lower than K3 than it would be 85dB-correct?
>
>
>
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[Elecraft] Load Impedance (was Re: Measuring SWR

[Richard Corfield]

I'm experimenting with portable antennas at the moment for my KX3 and,
rather than cut the 80m legs of my link dipole to get an antenna that
resonates on 60m, I've experimented with running it off centre. I've found
what looks like resonance at the right frequency range, based on low return
loss.

http://m0rjc.me.uk/screenshot_20190411-132334/

The problem is, that impedance is low. I guess it's being transformed down
by the 10m of feed line, as normal wisdom for an off-centre feed is high
impedance due to the lower currents and higher voltages towards the ends of
a half wave antenna. Considering a velocity factor of 0.66 that feed line
is about 1/4 wavelength long!

Presumably the KXAT-3 will tune this, but do I lose efficiency by having
what would be higher currents in its circuitry?

 - Richard

On Wed, 10 Apr 2019 at 22:56, Fred Jensen  wrote:

> It was a feeble attempt at humor, given the nearly countable infinity of
> posts here on baluns over the last few years including but not limited
> to what they are, what they aren't, how they work, do they even work?,
> and do they even exist at all.  Perhaps my attempt was more feeble than
> I thought. [:-) And, yes I know that "near infinity" is meaningless.
>
> 73,
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
>
> On 4/10/2019 11:13 AM, Bob McGraw K4TAX wrote:
> > Hu...see: http://www.dj0ip.de/balun-stuff/
> >
> > I seem to think this fellow has a good grasp about the "alien origin"
> > of baluns.
> >
> > 73
> > Bob, K4TAX
> >
> >
> > On 4/10/2019 12:23 PM, Fred Jensen wrote:
> >> It also spawned the "balun," a mysterious device that may be of alien
> >> origin since no one seems to know exactly what it does or how it does
> >> it.
> >
>
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Re: [Elecraft] Power output keeps folding back to 5 watts on my KX2

[Richard Corfield]

Don't Elecraft recommend using lower power for high duty digital modes?
(Though FT8 us 15s bursts so not as high duty as some).

 - Richard

On Mon, 18 Mar 2019 at 18:46, Tommy  wrote:

>Ahhh, O.K., with my 13.2v Astron it's showing 10.3 - 10.8. I guess
> for now with this power supply I'll have to settle for 5 watts. Thank
> you for the quick reply.
>
> Tom - KB2SMS
>
>
> On 3/18/19 2:36 PM, Walter Underwood wrote:
> > Set the display to show the power supply voltage and watch it while you
> transmit. The transmitter requires a voltage over 11 V for more than 5 W.
> >
> > If the voltage is dropping below 11 V, that is the problem.
> >
> > This in the specifications section of the KX3 manual.
> >
> > wunder
> > K6WRU
> > Walter Underwood
> > CM87wj
> > http://observer.wunderwood.org/ (my blog)
> >
> >> On Mar 18, 2019, at 11:33 AM, Tommy  wrote:
> >>
> >> Hi folks,
> >>
> >>   I'm running FT8 with a KX2 powered by a power supply. The rig
> keeps folding back from 10-12 watts to 5 every time and it's barely even
> warm.  I'll set it to 12W for instance, it'll transmit fine at that level
> but when done cut back to 5w. I don't transmit often enough for it to get
> hot enough to protect itself. AGC is off. Any ideas? I appreciate any
> feedback.
> >>
> >> 73 de Tom - KB2SMS
> >>
> >> __
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Re: [Elecraft] Should I worry about the toroids in the KXAT3 with vibration when carrying?

[Richard Corfield]

That sounds excellent. Maybe I'm being over-protective. New Side-KX panels
and lid arrived today (after spending quite some time in Customs!).

 - Richard

On Wed, 6 Mar 2019 at 16:49, Gmail - George  wrote:

> Richard,
> My KXAT3 goes down many unpaved gravel roads in the mountains of North
> Georgia and has for many years - since June 2012.
> At times we joke that the roads are actually potholes inter-connected by
> short stretches of gravel pavement.
> The KX3 lives in the cab of a Ranger pick-up mounted on a seat bolt
> mounted
> post.
> Occasionally I have had to retighten the mount bolts but have not needed
> to
> repair anything in the radio.
>
> 73
> George AI4VZ
>
> -----Original Message-
> From: Richard Corfield
> > >
> > > The toroids don't seem fastened down in any way. Cycling with it in my
> > > pannier bag today over our rubbish roads I was a bit worried about it.
> > > Could they shake loose given the vibration? Do I need to do anything to
> > > protect them? (Though I note instruction requiring them to be movable
> > > should I ever install the 2m module).
> > >
> > > Thanks
> > > - Richard
>
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Re: [Elecraft] Should I worry about the toroids in the KXAT3 with vibration when carrying?

[Richard Corfield]

Thanks.
I do think I'll be more careful with how I pack it if cycling - right way
up so any jolting forces are supported by the board. We have potholes here,
though the bike has its larger tyres and the radio is well packed.

 - Richard


On Tue, 5 Mar 2019 at 18:22, Wayne Burdick  wrote:

> Hi Richard,
>
> The toroids weigh almost nothing and the wire is very strong. We've never
> had an issue with toroids coming loose under normal levels of vibration.
>
> 73,
> Wayne
> N6KR
>
>
> > On Mar 5, 2019, at 10:11 AM, Richard Corfield <
> richard.corfi...@gmail.com> wrote:
> >
> > The toroids don't seem fastened down in any way. Cycling with it in my
> > pannier bag today over our rubbish roads I was a bit worried about it.
> > Could they shake loose given the vibration? Do I need to do anything to
> > protect them? (Though I note instruction requiring them to be movable
> > should I ever install the 2m module).
> >
> > Thanks
> > - Richard
> > __
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[Elecraft] Should I worry about the toroids in the KXAT3 with vibration when carrying?

[Richard Corfield]

The toroids don't seem fastened down in any way. Cycling with it in my
pannier bag today over our rubbish roads I was a bit worried about it.
Could they shake loose given the vibration? Do I need to do anything to
protect them? (Though I note instruction requiring them to be movable
should I ever install the 2m module).

Thanks
 - Richard
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