Re: [Elecraft] Running high power

[Wes]

Actually, he does https://www.dj0ip.com/about_ocfd


On 11/24/2022 12:31 PM, Edward Mccann wrote:

Kent:

I find that while your named expert with “more practical research than anyone 
on the planet”will likely claim expertise in just about anything, I have never 
seen anything observational, analytical, or anecdotal written by him on RFI in 
general or specifically associated with the OCFD.

I suggest you stick with K9YC, Owen Duffy and Tom Rauch.

Ed McCann
AG6CX




__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Edward Mccann]

Kent:

I find that while your named expert with “more practical research than anyone 
on the planet”will likely claim expertise in just about anything, I have never 
seen anything observational, analytical, or anecdotal written by him on RFI in 
general or specifically associated with the OCFD.

I suggest you stick with K9YC, Owen Duffy and Tom Rauch.

Ed McCann
AG6CX

> On Nov 24, 2022, at 8:46 AM, K9ZTV  wrote:
> 
> Amen to everything Steve says.
> 
> DJ0IP, who has done more practical research on off-center-fed dipoles than 
> probably anyone on the planet, has concluded they are fine up to 500-700 
> watts, but problematic above that and not recommended.
> 
> 73,
> Kent
> K9ZTV
> 
>> On Nov 24, 2022, at 9:37 AM, Steve Hall<99sun...@gmail.com> wrote:
>> 
>> Certainly as you increase power you are more likely to cause undesirable
>> effects in the home.  Now I am going to make a generalization that I have
>> found true.  The antenna type makes a significant difference in
>> interference.  Unbalanced antennas introduce more RF into the home as
>> opposed to balanced antennas.  An end-fed or off-center fed causes far more
>> problems than a dipole or inverted Vee.   I have proven this to myself over
>> and over.
>> __
>> 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 k9...@socket.net 
>> 
> 
> __
> 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 edwmcc...@gmail.com
__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Jim Brown]

On 11/24/2022 8:45 AM, K9ZTV wrote:

Amen to everything Steve says.


Yes.


DJ0IP, who has done more practical research on off-center-fed dipoles than 
probably anyone on the planet, has concluded they are fine up to 500-700 watts, 
but problematic above that and not recommended.


Those conclusions are VERY strongly dependent on where the antenna is 
installed with respect to victim equipment, and what victim equipment is 
in the home.


In addition, almost anything fed by open wire line, especially OCF 
dipoles, are magnets for RX noise.


73, Jim K9YC


73,
Kent
K9ZTV


On Nov 24, 2022, at 9:37 AM, Steve Hall<99sun...@gmail.com>  wrote:

Certainly as you increase power you are more likely to cause undesirable
effects in the home.  Now I am going to make a generalization that I have
found true.  The antenna type makes a significant difference in
interference.  Unbalanced antennas introduce more RF into the home as
opposed to balanced antennas.  An end-fed or off-center fed causes far more
problems than a dipole or inverted Vee.   I have proven this to myself over
and over.


__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[dobox]

Steve, curious about what changes you make to balance and chokes for the 
different antennas.de Dave K5MWR Sent from my Verizon, Samsung Galaxy smartphone
 Original message From: Steve Hall <99sun...@gmail.com> Date: 
11/24/22  09:35  (GMT-06:00) To: elecraft@mailman.qth.net Subject: Re: 
[Elecraft] Running high power Certainly as you increase power you are more 
likely to cause undesirableeffects in the home.  Now I am going to make a 
generalization that I havefound true.  The antenna type makes a significant 
difference ininterference.  Unbalanced antennas introduce more RF into the home 
asopposed to balanced antennas.  An end-fed or off-center fed causes far 
moreproblems than a dipole or inverted Vee.   I have proven this to myself 
overand 
over.__Elecraft 
mailing listHome: http://mailman.qth.net/mailman/listinfo/elecraftHelp: 
http://mailman.qth.net/mmfaq.htmPost: mailto:elecr...@mailman.qth.netThis list 
hosted by: http://www.qsl.netPlease help support this email list: 
http://www.qsl.net/donate.htmlMessage delivered to do...@suddenlink.net 
__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Tom Doligalski via Elecraft]

Suggest that this thread has migrated greatly from one directly relevant to 
Elecraft equipment. 

Tom W4KX

Sent from my iPad 

> On Nov 24, 2022, at 11:45 AM, K9ZTV  wrote:
> 
> Amen to everything Steve says.
> 
> DJ0IP, who has done more practical research on off-center-fed dipoles than 
> probably anyone on the planet, has concluded they are fine up to 500-700 
> watts, but problematic above that and not recommended.
> 
> 73,
> Kent
> K9ZTV
> 
>> On Nov 24, 2022, at 9:37 AM, Steve Hall<99sun...@gmail.com> wrote:
>> 
>> Certainly as you increase power you are more likely to cause undesirable
>> effects in the home.  Now I am going to make a generalization that I have
>> found true.  The antenna type makes a significant difference in
>> interference.  Unbalanced antennas introduce more RF into the home as
>> opposed to balanced antennas.  An end-fed or off-center fed causes far more
>> problems than a dipole or inverted Vee.   I have proven this to myself over
>> and over.
>> __
>> 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 k9...@socket.net 
>> 
> 
> __
> 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 w...@mac.com
__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[K9ZTV]

Amen to everything Steve says.

DJ0IP, who has done more practical research on off-center-fed dipoles than 
probably anyone on the planet, has concluded they are fine up to 500-700 watts, 
but problematic above that and not recommended.

73,
Kent
K9ZTV

> On Nov 24, 2022, at 9:37 AM, Steve Hall<99sun...@gmail.com> wrote:
> 
> Certainly as you increase power you are more likely to cause undesirable
> effects in the home.  Now I am going to make a generalization that I have
> found true.  The antenna type makes a significant difference in
> interference.  Unbalanced antennas introduce more RF into the home as
> opposed to balanced antennas.  An end-fed or off-center fed causes far more
> problems than a dipole or inverted Vee.   I have proven this to myself over
> and over.
> __
> 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 k9...@socket.net 
> 

__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Steve Hall]

Certainly as you increase power you are more likely to cause undesirable
effects in the home.  Now I am going to make a generalization that I have
found true.  The antenna type makes a significant difference in
interference.  Unbalanced antennas introduce more RF into the home as
opposed to balanced antennas.  An end-fed or off-center fed causes far more
problems than a dipole or inverted Vee.   I have proven this to myself over
and over.
__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Lyn Norstad]

Al -

I haven't the slightest idea what you're talking about.

There - now I feel good!

Actually, I do have a "slight" idea.  My antenna is a 360 foot EDZ (cut for 3.5 
MHz).  Its center fed with about 160' of 600 ohm true ladder line.  That 
terminates in the attic with a hybrid balun (4:1 impedance transformer and 1:1 
common mode choke) feeding a short piece of coax going to the KPA/KAT500 combo. 
 Tuning is excellent on all bands, 160-6m.  All the standard grounding and 
shielding is in place.

I did have a slight bit of RF in the shack on 10 meters (it would cause a mouse 
to lock up), but I fixed that with a couple turns of the mouse cable around a 
#31 ferrite core.

The only troublesome issue is due to the proximity of one end of the EDZ to the 
house, right outside the second floor MBa.  We have a Kohler Air Jet tub that 
"turns on" the blowers if I transmit using JS8Call on 40 meters.  But that's 
it.  Unfortunately the "under tub" control wiring is not long enough to do any 
significant "core wrapping" so I have been putting up with it (I seldom use 
JS8Call anymore anyway).

73
Lyn, WØLEN

-Original Message-
From: elecraft-boun...@mailman.qth.net 
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Al Lorona
Sent: Wednesday, November 23, 2022 10:06 AM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] Running high power

Thank you for all your responses. I did not mean my question to solicit the 
thousands of ways of solving this problem, but merely a poll of hams' 
experiences running high power. Based on all of the private and public 
responses I received, it's about 50% who've had problems with consumer 
equipment and high power.

If the problems are caused by simple RF overload of the piece of equipment, 
I've never understood why balanced or unbalanced antenna systems make any 
difference. If your 1500 W signal induces a large interferer on the circuitry 
of your internet modem or garage door opener, the device has no idea whether 
you're using a Yagi or a dipole or a vertical or whatever. It's just being 
overloaded because it's in the near field of the antenna and has very poor 
rejection and filtering. You could have the best-balanced antenna system in the 
world and still get into a poorly-shielded modem, couldn't you? The 
interference isn't coming in through the wires, it's coming in through the air!

I tend to resonate with K9YC's assertion that there are a whole lot of devices 
out there that are designed badly, susceptible to the slightest overload. When 
I look at my own situation I notice that I have tons of devices that were 
completely unaffected. My telephones, lights, garage doors, overhead fans, 
smart thermostat, and many others-- all of which have RF circuitry to one 
degree or another-- were never bothered.

Taking the FM radio in the kitchen as an example, you could make the argument 
that since its whole purpose in life is to receive weak signals, that it's 
particularly vulnerable to a large HF signal. But not a single person mentioned 
that they've ever heard themselves coming through their FM radio. I must have 
the only cheap table radio in America!

Anyway, I envy those of you who told me, "I haven't the slightest idea what 
you're talking about." 

R,

Al  W6LX

__
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 l...@lnainc.com 

__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Edward Mccann]

Ed:

If she’s lucky she could stream it on her new I-pad you buy her for Christmas !

Ed McCann
AG6CX

> On Nov 23, 2022, at 8:42 AM, Ed Cole  wrote:
> 
> I only have one RFI issue with my K3+KXPA100: running 80w on 50.125 SSB.
> 
> Seems my wife has her portable radio tuned to 100.1 MHz FM in the next room.  
> 50.125 x2 = 100.25 "ouch"!
> 
> Antenna is 20-foot high on tower attached to end of the house.
> 
> Guess I need a "good" harmonic filter.
> 
> I had one on my Harris 1000w 6m amp (converted ch.2 TV amp), but it was sold 
> with the amp.
> 
> When I get my MRF-1K50H LDMOS amp running 1200w on 160-6m will be interesting 
> to see how well the LP filters do. 
> 
> 73, Ed - KL7UW
> __
> 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 edwmcc...@gmail.com 
__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[James F. Boehner, MD via Elecraft]

Al,

I saw your question and saved it, as I knew you would be getting much better 
responses than I can give.  I have five amplifiers, as I tend to like building 
stations.

You received the responses I expected.  Grounding and bonding are indeed 
important and great information is found on K9YC's page as well as the ARRL 
publication "Grounding and Bonding for the Radio Amateur".  Yes, mix 31 
ferrites are your friend.  There are many sources; I bought mine from Pro 
Audio.  Sadly, many consumer devices are very poorly designed for RF 
environments.  Some problems can be mitigated, some not.

I do not know if anyone has talked about using a well-tuned antenna system, 
keeping SWR low and RF out of the shack.  

I am fortunate that the only interference to devices in my home occur on 160, 
but I'm sure most of that is because I'm using an antenna similar to a G5RV fed 
with 450 ohm twin lead, I short the twin lead and then use an UNUN and antenna 
tuner to achieve resonance. (?Marconi "T"?)  I do have a counterpoise.

I know many do not talk about amplifiers as they are shamed for using high 
power.  Whatever.  I saw someone at the 2019 Dayton Hamvention with a shirt 
that said "1500 watts - 1 watt = QRP!"  No shame there.

The one thing I do know, the problems that you can get from a high-power home 
installation do not even come close to running high power mobile.  That WAS a 
nightmare.

The one universal thing about amplifiers is that when the doorbell rings, the 
amp gets turned off!

Good luck-this is an interesting journey!

'73 de JIM N2ZZ



-Original Message-
From: elecraft-boun...@mailman.qth.net  On 
Behalf Of Al Lorona
Sent: Wednesday, November 23, 2022 11:06 AM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] Running high power

Thank you for all your responses. I did not mean my question to solicit the 
thousands of ways of solving this problem, but merely a poll of hams' 
experiences running high power. Based on all of the private and public 
responses I received, it's about 50% who've had problems with consumer 
equipment and high power.

If the problems are caused by simple RF overload of the piece of equipment, 
I've never understood why balanced or unbalanced antenna systems make any 
difference. If your 1500 W signal induces a large interferer on the circuitry 
of your internet modem or garage door opener, the device has no idea whether 
you're using a Yagi or a dipole or a vertical or whatever. It's just being 
overloaded because it's in the near field of the antenna and has very poor 
rejection and filtering. You could have the best-balanced antenna system in the 
world and still get into a poorly-shielded modem, couldn't you? The 
interference isn't coming in through the wires, it's coming in through the air!

I tend to resonate with K9YC's assertion that there are a whole lot of devices 
out there that are designed badly, susceptible to the slightest overload. When 
I look at my own situation I notice that I have tons of devices that were 
completely unaffected. My telephones, lights, garage doors, overhead fans, 
smart thermostat, and many others-- all of which have RF circuitry to one 
degree or another-- were never bothered.

Taking the FM radio in the kitchen as an example, you could make the argument 
that since its whole purpose in life is to receive weak signals, that it's 
particularly vulnerable to a large HF signal. But not a single person mentioned 
that they've ever heard themselves coming through their FM radio. I must have 
the only cheap table radio in America!

Anyway, I envy those of you who told me, "I haven't the slightest idea what 
you're talking about." 

R,

Al  W6LX

__
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 jboehne...@yahoo.com 

__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Ed Cole]

I only have one RFI issue with my K3+KXPA100: running 80w on 50.125 SSB.

Seems my wife has her portable radio tuned to 100.1 MHz FM in the next 
room.  50.125 x2 = 100.25 "ouch"!


Antenna is 20-foot high on tower attached to end of the house.

Guess I need a "good" harmonic filter.

I had one on my Harris 1000w 6m amp (converted ch.2 TV amp), but it was 
sold with the amp.


When I get my MRF-1K50H LDMOS amp running 1200w on 160-6m will be 
interesting to see how well the LP filters do. spring, next year>


73, Ed - KL7UW
__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Al Lorona]

Thank you for all your responses. I did not mean my question to solicit the 
thousands of ways of solving this problem, but merely a poll of hams' 
experiences running high power. Based on all of the private and public 
responses I received, it's about 50% who've had problems with consumer 
equipment and high power.

If the problems are caused by simple RF overload of the piece of equipment, 
I've never understood why balanced or unbalanced antenna systems make any 
difference. If your 1500 W signal induces a large interferer on the circuitry 
of your internet modem or garage door opener, the device has no idea whether 
you're using a Yagi or a dipole or a vertical or whatever. It's just being 
overloaded because it's in the near field of the antenna and has very poor 
rejection and filtering. You could have the best-balanced antenna system in the 
world and still get into a poorly-shielded modem, couldn't you? The 
interference isn't coming in through the wires, it's coming in through the air!

I tend to resonate with K9YC's assertion that there are a whole lot of devices 
out there that are designed badly, susceptible to the slightest overload. When 
I look at my own situation I notice that I have tons of devices that were 
completely unaffected. My telephones, lights, garage doors, overhead fans, 
smart thermostat, and many others-- all of which have RF circuitry to one 
degree or another-- were never bothered.

Taking the FM radio in the kitchen as an example, you could make the argument 
that since its whole purpose in life is to receive weak signals, that it's 
particularly vulnerable to a large HF signal. But not a single person mentioned 
that they've ever heard themselves coming through their FM radio. I must have 
the only cheap table radio in America!

Anyway, I envy those of you who told me, "I haven't the slightest idea what 
you're talking about." 

R,

Al  W6LX

__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[john]

What antenna, choke and feedline are you using? 

John KK9A


Al Lorona W6LX wrote:

I'm really curious to ask those on this list who run high power:

Do you find that you get into all kinds of devices around the house?

I ran the KPA-500 in an extended manner for really the first time during the
Phone SS and immediately:

1/ interfered with FM broadcast radio.

2/ caused the internet to drop out every time I keyed up on the lower bands.

Am I the only one? Those of you who run high power all the time... how do
you deal with these annoyances?

Al  W6LX/4

__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Jerry Moore]

I'm 

-Original Message-
From: elecraft-boun...@mailman.qth.net  On 
Behalf Of Dave (NK7Z)
Sent: Wednesday, November 23, 2022 9:16 AM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] Running high power

Al,

Are you by chance running an end fed antenna?

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 11/23/22 05:59, Wes wrote:
> I run a KPA500 all of the time; essentially, I run a 500W transceiver.   
> I have never had an issue as you describe.  The only chokes in the 
> shack are the ones molded onto the various computer cables that come with 
> them.
> 
> Outside, I use a homebrew W2DU type balun (sorry Jim) at the feedpoint 
> of my 40-80M inverted-vee and a commercial sleeve balun on my little 
> triband beam. BTW, both of these antennas are used off-resonance, 
> tuned with a KPA500 in the shack for WARC bands. According to 
> conventional wisdom, I do everything wrong. Grounding and bonding is a 
> combination of single-point and daisy-chain.  I don't have pounds of 
> ferrite on every wire, I use a switch mode power supply for all of the 
> low voltage stuff and a Rigrunner distribution box.  And the whole 
> station runs on a 120V 20A circuit.
> 
> I suspect that you have a rectifying joint some place.
> 
> Wes  N7WS
> 
> On 11/22/2022 3:36 PM, Al Lorona wrote:
>> I'm really curious to ask those on this list who run high power:
>>
>> Do you find that you get into all kinds of devices around the house?
>>
>> I ran the KPA-500 in an extended manner for really the first time 
>> during the Phone SS and immediately:
>>
>> 1/ interfered with FM broadcast radio.
>>
>> 2/ caused the internet to drop out every time I keyed up on the lower 
>> bands.
>>
>> Am I the only one? Those of you who run high power all the time... 
>> how do you deal with these annoyances?
>>
>> Al  W6LX/4
>> ___
> 
> __
> 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 
> d...@nk7z.net
__
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 je...@carolinaheli.com 
__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Jerry Moore]

I'm constantly amazed at the lengths we'll go as hams to overcome the poor 
engineering and manufacture of consumer products.

-Original Message-
From: elecraft-boun...@mailman.qth.net  On 
Behalf Of Jim Brown
Sent: Wednesday, November 23, 2022 5:01 AM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] Running high power

On 11/22/2022 2:36 PM, Al Lorona wrote:
> 1/ interfered with FM broadcast radio.
> 
> 2/ caused the internet to drop out every time I keyed up on the lower bands.
> 
> Am I the only one? Those of you who run high power all the time... how do you 
> deal with these annoyances?

Both are caused by lousy design of the equipment. Band-aids are SERIOUS common 
mode chokes on every wire connected to the victim. Follow guidelines for HF 
transmitting chokes for the bands involved, winding each individual cable 
through a #31 2.4-in i.d. toroid. Those wires are receiving antennas coupling 
RF into that badly designed stuff, and chokes kill RF current on them.

http://k9yc.com/2018Cookbook.pdf

3/4-in and 1-in i.d. #31 clamp-ons can work with 4-5 turns, but they MUST be 
wound in sequence around the core. See the photo on page 10 in 
http://k9yc.com/KillingReceiveNoise.pdf

As Vic has noted, use a serious choke at the feedpoint of every antenna, use 
only coax-fed antennas, matched to the feedline resonant on the bands where 
they are used, using that same Cookbook as a guide. Try to locate antennas as 
far as practical from victim equipment. An end-fed antenna, vertical or 
otherwise, ending in the shack is a recipe for RFI to equipment. ALWAYS provide 
a serious counterpoise for any end-fed antenna. If you don't, that antenna will 
use everything in your home as a counterpoise, causing RFI.

In summary, take antennas seriously, -- their design, their location, chokes at 
the feedpoint, bonding in the shack. Avoiding the problems you describe is 
nothing more or less good engineering practice.

Also, some cable/DSL modems are notorious for RFI susceptibility. W8JI solved a 
problem by complaining to the vendor, who gave him a replacement. This usually 
requires taking the complaint up one or more levels.

73, Jim K9YC
__
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 je...@carolinaheli.com 
__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Dave (NK7Z)]

Al,

Are you by chance running an end fed antenna?

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 11/23/22 05:59, Wes wrote:
I run a KPA500 all of the time; essentially, I run a 500W transceiver.   
I have never had an issue as you describe.  The only chokes in the shack 
are the ones molded onto the various computer cables that come with them.


Outside, I use a homebrew W2DU type balun (sorry Jim) at the feedpoint 
of my 40-80M inverted-vee and a commercial sleeve balun on my little 
triband beam. BTW, both of these antennas are used off-resonance, tuned 
with a KPA500 in the shack for WARC bands. According to conventional 
wisdom, I do everything wrong. Grounding and bonding is a combination of 
single-point and daisy-chain.  I don't have pounds of ferrite on every 
wire, I use a switch mode power supply for all of the low voltage stuff 
and a Rigrunner distribution box.  And the whole station runs on a 120V 
20A circuit.


I suspect that you have a rectifying joint some place.

Wes  N7WS

On 11/22/2022 3:36 PM, Al Lorona wrote:

I'm really curious to ask those on this list who run high power:

Do you find that you get into all kinds of devices around the house?

I ran the KPA-500 in an extended manner for really the first time 
during the Phone SS and immediately:


1/ interfered with FM broadcast radio.

2/ caused the internet to drop out every time I keyed up on the lower 
bands.


Am I the only one? Those of you who run high power all the time... how 
do you deal with these annoyances?


Al  W6LX/4
___


__
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 d...@nk7z.net

__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Wes]

I run a KPA500 all of the time; essentially, I run a 500W transceiver.   I have 
never had an issue as you describe.  The only chokes in the shack are the ones 
molded onto the various computer cables that come with them.


Outside, I use a homebrew W2DU type balun (sorry Jim) at the feedpoint of my 
40-80M inverted-vee and a commercial sleeve balun on my little triband beam.  
BTW, both of these antennas are used off-resonance, tuned with a KPA500 in the 
shack for WARC bands. According to conventional wisdom, I do everything wrong. 
Grounding and bonding is a combination of single-point and daisy-chain.  I don't 
have pounds of ferrite on every wire, I use a switch mode power supply for all 
of the low voltage stuff and a Rigrunner distribution box.  And the whole 
station runs on a 120V 20A circuit.


I suspect that you have a rectifying joint some place.

Wes  N7WS

On 11/22/2022 3:36 PM, Al Lorona wrote:

I'm really curious to ask those on this list who run high power:

Do you find that you get into all kinds of devices around the house?

I ran the KPA-500 in an extended manner for really the first time during the 
Phone SS and immediately:

1/ interfered with FM broadcast radio.

2/ caused the internet to drop out every time I keyed up on the lower bands.

Am I the only one? Those of you who run high power all the time... how do you 
deal with these annoyances?

Al  W6LX/4
___


__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Jim Brown]

On 11/22/2022 2:36 PM, Al Lorona wrote:

1/ interfered with FM broadcast radio.

2/ caused the internet to drop out every time I keyed up on the lower bands.

Am I the only one? Those of you who run high power all the time... how do you 
deal with these annoyances?


Both are caused by lousy design of the equipment. Band-aids are SERIOUS 
common mode chokes on every wire connected to the victim. Follow 
guidelines for HF transmitting chokes for the bands involved, winding 
each individual cable through a #31 2.4-in i.d. toroid. Those wires are 
receiving antennas coupling RF into that badly designed stuff, and 
chokes kill RF current on them.


http://k9yc.com/2018Cookbook.pdf

3/4-in and 1-in i.d. #31 clamp-ons can work with 4-5 turns, but they 
MUST be wound in sequence around the core. See the photo on page 10 in

http://k9yc.com/KillingReceiveNoise.pdf

As Vic has noted, use a serious choke at the feedpoint of every antenna, 
use only coax-fed antennas, matched to the feedline resonant on the 
bands where they are used, using that same Cookbook as a guide. Try to 
locate antennas as far as practical from victim equipment. An end-fed 
antenna, vertical or otherwise, ending in the shack is a recipe for RFI 
to equipment. ALWAYS provide a serious counterpoise for any end-fed 
antenna. If you don't, that antenna will use everything in your home as 
a counterpoise, causing RFI.


In summary, take antennas seriously, -- their design, their location, 
chokes at the feedpoint, bonding in the shack. Avoiding the problems you 
describe is nothing more or less good engineering practice.


Also, some cable/DSL modems are notorious for RFI susceptibility. W8JI 
solved a problem by complaining to the vendor, who gave him a 
replacement. This usually requires taking the complaint up one or more 
levels.


73, Jim K9YC
__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Victor Rosenthal 4X6GP]

All of the information that you will get on bonding equipment and use of 
ferrites (31 mix seems best for HF) will help.
But in my opinion, the single most important thing you can do is to 
reduce common-mode RF flowing on your feedline. That requires a common 
mode choke at the feedpoint of your antenna, if it is fed with coax. If 
your feedline does not come away from your antenna at a 90 degree angle, 
it might also help to have a common-mode choke at the entry to your shack.
It's also the case that some arrangements of antenna and feedline are 
more susceptible to such problems: end-fed antennas in particular are 
often problematic, including verticals. A balanced antenna like a dipole 
or beam is best.
If the antenna is fed with window line or open line then a true balanced 
antenna tuner does a better job of reducing common mode currents than an 
unbalanced tuner followed by a balun.

I hope this helps.

73,
Victor, 4X6GP
Rehovot, Israel
Formerly K2VCO
CWops no. 5
http://www.qsl.net/k2vco

On 23/11/2022 0:36, Al Lorona wrote:

I'm really curious to ask those on this list who run high power:

Do you find that you get into all kinds of devices around the house?

I ran the KPA-500 in an extended manner for really the first time during the 
Phone SS and immediately:

1/ interfered with FM broadcast radio.

2/ caused the internet to drop out every time I keyed up on the lower bands.

Am I the only one? Those of you who run high power all the time... how do you 
deal with these annoyances?

Al  W6LX/4
__
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 k2vco@gmail.com

__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[James Bennett via Elecraft]

Al - I’m not on the RFI reflector, but wanted to give you a quick reply here, 
since it in a way does involve Elecraft things. I have a K4D, KPA500, KAT500 
and run RG-213 to a 30 foot tall Zerofive Flagpole vertical in the back yard - 
10 various length radials. I put isolation transformers on each end of the coax 
run. The main RFI issue I had with this setup, running 500 watts, was that I’d 
turn on the overhead lights in our two garage door openers. A couple mix 31 
ferrite clamp-ons at the opener motor box took care of that problem. Every 
situation is different. If you’ve got your equipment properly bonded together 
and grounded, then attack each device with ferrites. It’s a PITA, but not 
insurmountable.

Like Pete mentioned - there probably will be some RFI to deal with one way or 
the other. It’ll come from common mode current on your feed line or simply 
having some household device swamped by RF that it isn’t designed to handle. 
Trust the mix 31 ferrites - they are your friend! 

BTW - didn’t have that issue running my K4 at 100 watts - only when I got above 
about 350 did those lights turn on. :-(

Jim Bennett / K7TXA
Eagle, ID



> On Nov 22, 2022, at 3:36 PM, Al Lorona  wrote:
> 
> I'm really curious to ask those on this list who run high power:
> 
> Do you find that you get into all kinds of devices around the house?
> 
> I ran the KPA-500 in an extended manner for really the first time during the 
> Phone SS and immediately:
> 
> 1/ interfered with FM broadcast radio.
> 
> 2/ caused the internet to drop out every time I keyed up on the lower bands.
> 
> Am I the only one? Those of you who run high power all the time... how do you 
> deal with these annoyances?
> 
> Al  W6LX/4
> __
> 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 w6...@me.com

__
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 arch...@mail-archive.com 

Re: [Elecraft] Running high power

[Pete Smith N4ZR]

Al, you really should take this question to the r...@contesting.com 
reflector - there is a huge amount of experience--based information 
there from a number of RFI mavens. One of the most energetic and 
prolific is K9YC, who has written a number of very detailed papers on 
various aspects of RFI that are available on the web.  Google will find 
them for you - a good place to start is 
http://www.audiosystemsgroup.com/RFI-Ham.pdf


In answer to your question, most everyone has these issues to a larger 
or smaller degree. It probably makes best sense to start by making sure 
your station itself has proper bonding, grounding, and filtering as 
required.  Then go on and look at each of the devices being interfered 
with, and apply similar methods.


73, Pete N4ZR
Check out the new Reverse Beacon Network
web server at.
For spots, please use your favorite
"retail" DX cluster.

On 11/22/2022 5:36 PM, Al Lorona wrote:

I'm really curious to ask those on this list who run high power:

Do you find that you get into all kinds of devices around the house?

I ran the KPA-500 in an extended manner for really the first time during the 
Phone SS and immediately:

1/ interfered with FM broadcast radio.

2/ caused the internet to drop out every time I keyed up on the lower bands.

Am I the only one? Those of you who run high power all the time... how do you 
deal with these annoyances?

Al  W6LX/4
__
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 topete.n...@gmail.com  

__
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 arch...@mail-archive.com