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HI CUR on 40

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Jim Rhodes-2

HI CUR on 40

Today I find that I get a HI CUR error when transmitting at just a little
over 50 watts. Switched to a DL and find that on 40 meters my K3 draws more
current at 50 watts than it does on all the other bands. This is with the
tuner bypassed and hooked to one of my old cantennas. SWR shows flat on 40
and all other bands So I am guessing band pass filter issues. Has anyone
else had a similar experience with one band being way out of whack?

--
Jim K0XU
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N3ALN

Re: HI CUR on 40

I was getting this HI CUR message to and it was driving me CRAZY! I called
Elecraft and I was going to send my K3 back to them and then I saw a few
YouTube videos and I installed a TON of toroids on the K3 and Amp and every
wire in my shack and no more HI CUR message. Best of luck!

--
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Elecraft mailing list

Re: HI CUR on 40

Which tortoise did get and from whom?

73

Bill, WB9CAC

Sent from my iPhone

> On Oct 30, 2020, at 2:19 AM, N3ALN <[hidden email]> wrote:
>
> I was getting this HI CUR message to and it was driving me CRAZY! I called
> Elecraft and I was going to send my K3 back to them and then I saw a few
> YouTube videos and I installed a TON of toroids on the K3 and Amp and every
> wire in my shack and no more HI CUR message. Best of luck!
>
>
>
> --
> Sent from: http://elecraft.365791.n2.nabble.com/
> ______________________________________________________________
> Elecraft mailing list
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N3ALN

Re: HI CUR on 40

HI, I get this kit from Palomore for the K3 and I got another for my Yaesu
Quadra VL-1000. Take a good look at their website for what you will need.

https://palomar-engineers.com/ferrite-products/ferrite-cores/Elecraft-Transceiver-RFI-Kits-c46846169

--
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Jim Rhodes-2

Re: HI CUR on 40

Ferrites are probably not the answer here. Problem showed up with no
changes in configuration, and problem happens with a dummy load. Plus I
have ferrites in most of those locations already. This only happens on 40
meters and happens both with antenna connected and when dummy load
connected.

On Fri, Oct 30, 2020 at 5:43 AM N3ALN <[hidden email]> wrote:

> HI, I get this kit from Palomore for the K3 and I got another for my Yaesu
> Quadra VL-1000. Take a good look at their website for what you will need.
>
>
> https://palomar-engineers.com/ferrite-products/ferrite-cores/Elecraft-Transceiver-RFI-Kits-c46846169
>
>
>
> --
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> ______________________________________________________________
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>

--
Jim K0XU
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Jim Brown-10

Re: HI CUR on 40

In reply to this post by N3ALN

On 10/30/2020 3:43 AM, N3ALN wrote:
> HI, I get this kit from Palomore for the K3 and I got another for my Yaesu
> Quadra VL-1000. Take a good look at their website for what you will need.
>
> https://palomar-engineers.com/ferrite-products/ferrite-cores/Elecraft-Transceiver-RFI-Kits-c46846169
>

Total BS. They're trying to sell you stuff. NONE of this is necessary.
What IS critical is antenna design, how they are fed, simple bonding,
and the use of chokes at the feedpoint of each antenna.

For bonding, study http://k9yc.com/GroundingAndAudio.pdf

For chokes, study http://k9yc.com/2018Cookbook.pdf

For antennas, study the ARRL Handbook and Antenna Book.

Note that I'm not selling anything. :)

73, Jim K9YC

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VE3NR

Re: HI CUR on 40

It's really sad to see how some companies prey on people who don't have
the knowledge or the experience.
This is only one example!
Bert VE3NR

On 2020-10-30 13:31, Jim Brown wrote:

> On 10/30/2020 3:43 AM, N3ALN wrote:
>> HI, I get this kit from Palomore for the K3 and I got another for my
>> Yaesu
>> Quadra VL-1000. Take a good look at their website for what you will
>> need.
>>
>> https://palomar-engineers.com/ferrite-products/ferrite-cores/Elecraft-Transceiver-RFI-Kits-c46846169
>>
>>
>
> Total BS. They're trying to sell you stuff. NONE of this is necessary.
> What IS critical is antenna design, how they are fed, simple bonding,
> and the use of chokes at the feedpoint of each antenna.
>
> For bonding, study http://k9yc.com/GroundingAndAudio.pdf
>
> For chokes, study http://k9yc.com/2018Cookbook.pdf
>
> For antennas, study the ARRL Handbook and Antenna Book.
>
> Note that I'm not selling anything. :)
>
> 73, Jim K9YC
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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N3ALN

Re: HI CUR on 40

This post was updated on .

I was getting this HI CUR error only with my Directive Systems 6 Meter
antenna (DS50-5) that has a 1:1 SWR I hope they know antenna design? Maybe
not? The toroids fixed my issue. I just love how some on the forum or so
judgmental, it is a only a freaking hobby, chill.

--
Sent from: http://elecraft.365791.n2.nabble.com/
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David Olean

Re: HI CUR on 40

Hello Alan

That was my antenna design. It has a teflon coax 1/2 wave balun that
kills RF on the shield side of the coax, but there is not much you can
do about near field energy getting picked up by the outside of the coax
due to radiation. It is best to tape the coax down snugly along the
boom and masting etc. Still, it does not hurt to add more RF chokes to
any antenna! It is pretty easy for RF energy to get impressed on the
outside of the coax in any typical installation. The balun at the
antenna only keeps the energy from the coax center conductor from going
to the outside of the coax at the feedpoint.

The way I check for decoupling effectiveness is to match the antenna
really well, and then run your hand along the outside of the feedline
near the feed. While looking at the screen of a network analyzer, you
can see little perturbations in the return loss 20 or 30 dB down if
there is RF leaking to the outside of the feedline. This is a
qualitative test and you can estimate the bandwidth of the decoupling
network. You will see larger return loss change amounts away from the
resonant frequency of the decoupling element. This won't apply to
ferrites, as they can be broadband, but with a quarter wave choke, or
similar, you can definitely see the effect.

73

Dave K1WHS

On 10/31/2020 5:39 AM, N3ALN wrote:

> Hum, I was getting this HI CUR error only with my Directive Systems 6 Meter
> antenna (DS50-5) that has a 1:1 SWR I hope they know antenna design? Maybe
> not? The toroids fixed my issue. I just love how some of the forum or so
> judgmental, it is a only a freaking hobby, chill.
>
>
>
> --
> Sent from: http://elecraft.365791.n2.nabble.com/
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
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>
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Elecraft mailing list

Re: HI CUR on 40

Dave
So where is the optimum place to place the ferrites for this antenna if you have a problem like Alan described?

Does the near field extend roughly to half the stacking distance of that antenna (i.e. 6 feet or so), making that the best place for the ferrites?

Does a mostly vertical coax passing through the near field of a horizontally polarized antenna (i.e. an antenna side mounted to a tower) need ferrites?

Do you need to decouple ALL of the rest of your coaxes and control lines at the lower near field edge of that antenna (or at some other point)? I have heard that argument (decouple everything) made to improve performance of inverted L antennas on 160 meters located near a tower.

73, Mike, W3IP

On Saturday, October 31, 2020, 10:04:48 AM EDT, David Olean <[hidden email]> wrote:

Hello Alan

That was my antenna design. It has a teflon coax 1/2 wave balun that
kills RF on the shield side of the coax, but there is not much you can
do about near field energy getting picked up by the outside of the coax
due to radiation. It is best to tape the coax down snugly along the
boom and masting etc. Still, it does not hurt to add more RF chokes to
any antenna! It is pretty easy for RF energy to get impressed on the
outside of the coax in any typical installation. The balun at the
antenna only keeps the energy from the coax center conductor from going
to the outside of the coax at the feedpoint.

The way I check for decoupling effectiveness is to match the antenna
really well, and then run your hand along the outside of the feedline
near the feed. While looking at the screen of a network analyzer, you
can see little perturbations in the return loss 20 or 30 dB down if
there is RF leaking to the outside of the feedline. This is a
qualitative test and you can estimate the bandwidth of the decoupling
network. You will see larger return loss change amounts away from the
resonant frequency of the decoupling element. This won't apply to
ferrites, as they can be broadband, but with a quarter wave choke, or
similar, you can definitely see the effect.

73

Dave K1WHS

On 10/31/2020 5:39 AM, N3ALN wrote:

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Jim Brown-10

Re: HI CUR on 40

In reply to this post by N3ALN

On 10/31/2020 2:39 AM, N3ALN wrote:
> I just love how some of the forum or so
> judgmental, it is a only a freaking hobby, chill.

NOT judgemental, but an attempt by those of us who understand how stuff
actually works to share that with others (the several thousand hams who
read this and other email reflectors) so that false ideas and solutions
are less likely to be accepted and propagated.

Anyone who doesn't want to learn is welcome to use their delete key on
my posts.

73, Jim K9YC
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David Olean

Re: HI CUR on 40

In reply to this post by Elecraft mailing list

Hi Mike,

I would put the ferrite at the end of the coax before it goes into the
rig if there were rf coming down the coax. Common mode energy can and
will get on the outside of the coax. I am not an expert on this, but I
would expect that any problem that would cause a transmitter to
misbehave would involve strong levels most likely encountered near the
antenna where the fields could be high. Of all the folks that have
used that 5 element six meter yagi, (me included) No one has ever had a
stray RF problem. Running the coax perpendicular to the elements and
tied down to the boom is all that is needed to keep things quiet. I am
at a loss to explain any other outcome.

I suppose there could be a fault in the balun area, but I would think
that the SWR would climb well above 1:1 in that case.

Dave K1WHS

On 10/31/2020 11:13 AM, M Cresap wrote:

> Dave
>
> So where is the optimum place to place the ferrites for this antenna
> if you have a problem like Alan described?
>
> Does the near field extend roughly to half the stacking distance of
> that antenna (i.e. 6 feet or so), making that the best place for the
> ferrites?
>
> Does a mostly vertical coax passing through the near field of a
> horizontally polarized antenna (i.e. an antenna side mounted to a
> tower) need ferrites?
>
> Do you need to decouple ALL of the rest of your coaxes and control
> lines at the lower near field edge of that antenna (or at some other
> point)? I have heard that argument (decouple everything) made to
> improve performance of inverted L antennas on 160 meters located near
> a tower.
>
> 73, Mike, W3IP
>
> On Saturday, October 31, 2020, 10:04:48 AM EDT, David Olean
> <[hidden email]> wrote:
>
>
> Hello Alan
>
> That was my antenna design. It has a teflon coax 1/2 wave balun that
> kills RF on the shield side of the coax, but there is not much you can
> do about near field energy getting picked up by the outside of the coax
> due to radiation. It is best to tape the coax down snugly along the
> boom and masting etc. Still, it does not hurt to add more RF chokes to
> any antenna! It is pretty easy for RF energy to get impressed on the
> outside of the coax in any typical installation. The balun at the
> antenna only keeps the energy from the coax center conductor from going
> to the outside of the coax at the feedpoint.
>
> The way I check for decoupling effectiveness is to match the antenna
> really well, and then run your hand along the outside of the feedline
> near the feed. While looking at the screen of a network analyzer, you
> can see little perturbations in the return loss 20 or 30 dB down if
> there is RF leaking to the outside of the feedline. This is a
> qualitative test and you can estimate the bandwidth of the decoupling
> network. You will see larger return loss change amounts away from the
> resonant frequency of the decoupling element. This won't apply to
> ferrites, as they can be broadband, but with a quarter wave choke, or
> similar, you can definitely see the effect.
>
> 73
>
> Dave K1WHS
>
> On 10/31/2020 5:39 AM, N3ALN wrote:
>
> > Hum, I was getting this HI CUR error only with my Directive Systems
> 6 Meter
> > antenna (DS50-5) that has a 1:1 SWR I hope they know antenna design?
> Maybe
> > not? The toroids fixed my issue. I just love how some of the forum or so
> > judgmental, it is a only a freaking hobby, chill.
> >
> >
> >
> > --
> > Sent from: http://elecraft.365791.n2.nabble.com/
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email] <mailto:[hidden email]>
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to [hidden email] <mailto:[hidden email]>
>
> ______________________________________________________________
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David Herring

Re: HI CUR on 40

If there is ever any question about where to place ferrites, I’ll say in general, put the ferrites at both ends of the coax (unless its a really short run).

Some may argue that that is overkill. While there are always exceptional circumstances, I would in general respectfully disagree with them if they did. While the benefits of placing them at the feed point are well documented, I have found that replicating the ferrites at the other end of the coax generally reduces noise in the receiver, making it possible to hear and thus work more stations… ;-)

It would also be part of the solution to rf in the shack, provided that the ferrites provide enough choking impedance. 5000 ohms at the frequencies in question would likely do, but referring to K9YC’s papers for the specifics is advised.

Ferrites at both ends, along with proper bounding and grounding of the whole station a la K9YC has always worked well for me.

73,
David - N5DCH

> On Oct 31, 2020, at 7:07 PM, David Olean <[hidden email]> wrote:
>
>
> Hi Mike,
>
> I would put the ferrite at the end of the coax before it goes into the rig if there were rf coming down the coax. Common mode energy can and will get on the outside of the coax. I am not an expert on this, but I would expect that any problem that would cause a transmitter to misbehave would involve strong levels most likely encountered near the antenna where the fields could be high. Of all the folks that have used that 5 element six meter yagi, (me included) No one has ever had a stray RF problem. Running the coax perpendicular to the elements and tied down to the boom is all that is needed to keep things quiet. I am at a loss to explain any other outcome.
>
> I suppose there could be a fault in the balun area, but I would think that the SWR would climb well above 1:1 in that case.
>
> Dave K1WHS
>
> On 10/31/2020 11:13 AM, M Cresap wrote:
>> Dave
>>
>> So where is the optimum place to place the ferrites for this antenna if you have a problem like Alan described?
>>
>> Does the near field extend roughly to half the stacking distance of that antenna (i.e. 6 feet or so), making that the best place for the ferrites?
>>
>> Does a mostly vertical coax passing through the near field of a horizontally polarized antenna (i.e. an antenna side mounted to a tower) need ferrites?
>>
>> Do you need to decouple ALL of the rest of your coaxes and control lines at the lower near field edge of that antenna (or at some other point)? I have heard that argument (decouple everything) made to improve performance of inverted L antennas on 160 meters located near a tower.
>>
>> 73, Mike, W3IP
>>
>> On Saturday, October 31, 2020, 10:04:48 AM EDT, David Olean <[hidden email]> wrote:
>>
>>
>> Hello Alan
>>
>> That was my antenna design. It has a teflon coax 1/2 wave balun that
>> kills RF on the shield side of the coax, but there is not much you can
>> do about near field energy getting picked up by the outside of the coax
>> due to radiation. It is best to tape the coax down snugly along the
>> boom and masting etc. Still, it does not hurt to add more RF chokes to
>> any antenna! It is pretty easy for RF energy to get impressed on the
>> outside of the coax in any typical installation. The balun at the
>> antenna only keeps the energy from the coax center conductor from going
>> to the outside of the coax at the feedpoint.
>>
>> The way I check for decoupling effectiveness is to match the antenna
>> really well, and then run your hand along the outside of the feedline
>> near the feed. While looking at the screen of a network analyzer, you
>> can see little perturbations in the return loss 20 or 30 dB down if
>> there is RF leaking to the outside of the feedline. This is a
>> qualitative test and you can estimate the bandwidth of the decoupling
>> network. You will see larger return loss change amounts away from the
>> resonant frequency of the decoupling element. This won't apply to
>> ferrites, as they can be broadband, but with a quarter wave choke, or
>> similar, you can definitely see the effect.
>>
>> 73
>>
>> Dave K1WHS
>>
>> On 10/31/2020 5:39 AM, N3ALN wrote:
>>
>> > Hum, I was getting this HI CUR error only with my Directive Systems 6 Meter
>> > antenna (DS50-5) that has a 1:1 SWR I hope they know antenna design? Maybe
>> > not? The toroids fixed my issue. I just love how some of the forum or so
>> > judgmental, it is a only a freaking hobby, chill.
>> >
>> >
>> >
>> > --
>> > Sent from: http://elecraft.365791.n2.nabble.com/
>> > ______________________________________________________________
>> > Elecraft mailing list
>> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> > Help: http://mailman.qth.net/mmfaq.htm
>> > Post: mailto:[hidden email] <mailto:[hidden email]> <mailto:[hidden email] <mailto:[hidden email]>>
>> >
>> > This list hosted by: http://www.qsl.net <http://www.qsl.net/>
>> > Please help support this email list: http://www.qsl.net/donate.html <http://www.qsl.net/donate.html>
>> > Message delivered to [hidden email] <mailto:[hidden email]> <mailto:[hidden email] <mailto:[hidden email]>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft <http://mailman.qth.net/mailman/listinfo/elecraft>
>> Help: http://mailman.qth.net/mmfaq.htm <http://mailman.qth.net/mmfaq.htm>
>> Post: mailto:[hidden email] <mailto:[hidden email]> <mailto:[hidden email] <mailto:[hidden email]>>
>>
>> This list hosted by: http://www.qsl.net <http://www.qsl.net/>
>> Please help support this email list: http://www.qsl.net/donate.html <http://www.qsl.net/donate.html>
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> ______________________________________________________________
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Jim Brown-10

Re: HI CUR on 40

In reply to this post by David Olean

On 10/31/2020 6:07 PM, David Olean wrote:
> I would put the ferrite at the end of the coax before it goes into the
> rig if there were rf coming down the coax. Common mode energy can and
> will get on the outside of the coax. I am not an expert on this,
I AM an expert on this. :) The most important place for a choke in any
antenna system is at the feedpoint. It's function is to prevent the
feedline from becoming part of the antenna by adding a very high common
mode impedance to the common mode circuit. The only good reasons for a
choke elsewhere along the line are

1) to prevent the feedline from becoming a parasitic element of another
antenna; for example, I choke the coax feedlines to my high (125 ft)
dipoles for 80 and 40 so that they do not become parasitic to my three
160M verticals. e

2) to prevent coupling shield current by a mechanism quantified as the
"transfer impedance" of the coax shield. It is the ratio of the
differential voltage generated inside the coax as a result of shield
current. Its unit is Ohms, lower is better, and the lower limit is the
RF resistance of the shield at the frequency of interest. But the
quality, density, and uniformity of the shield makes an additive
contribution -- a poor quality shield increases the transfer impedance.

Both of these measures minimize inter-station interference, both in-band
and cross-band. W6GJB's contesting trailer has antennas for 15, 20, 40,
and 80 supported on a single pneumatic mast, with their feedpoints
within about 2 ft of each other. Because they are very effectively
choked, and because we have dual stubs on the outputs of the power amps
for the two stations, we can operate on adjacent bands at 500W
(K3/KPA500) with minimal interference from the lower frequency station's
harmonics to the higher frequency station. One day, Glen rebuilt the
connection at the antenna and accidentally left out the choke, and the
interstation interference was terrible.

A choke at the rig is only a band-aid for failure to do proper grounding
and bonding in the shack and throughout the house. See N0AX's ARRL book
on the topic, on which I collaborated, or the slides for my tutorial
talk at Pacificon, Visalia, and to various ham clubs.
http://k9yc.com/GroundingAndAudio.pdf

The half-wave section of line you described in an earlier post may take
care of the feedpoint for one band (and it may not be as effective as a
well-designed choke), but it's not a solution for other bands. Properly
designed chokes can cover multiple adjacent bands. See
http://k9yc.com/2018Cookbook.pdf

73, Jim K9YC

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