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K3 TVI on 40 meters only

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mjpilgrim

K3 TVI on 40 meters only

Recently replaced my ic-7600 with a new to me K3. I don't recall this issue
when using the ic7600, but I now have TVI in my u-Verse TVs when using the
K3 on 40 meters, primarily on CW, with diminishing evidence on SSB up to
7.2.50 but okay above that. The symptom is pixilation on the screen, then
audio blanks out, and finally the set top box will completely lose signal.
This occurs on two TV operating on wireless set top boxes, and two hardwired
with CAT-5 cabling. I have tried on three separate end-fed long wires fed
by coax through a 9:1 UNUN, two with feedline length of 100' and the third
approximately 60 feet. I can operate satisfactorily on all bands from160 to
10 Meters with exception of 40 Meters on all three antennas. The K3 auto
tuner indicates 1 bar of SWR with output power anywhere from 10 to 100
Watts. I have also used an external ATU with same results. I have looked
at everything I can think of, including terminating each antenna port with a
dummy load, but to no avail. I've traced out all grounds and coax
connections. Nothing helps. What might I be overlooking? Is there an
inherent issue in the K3 which might attribute to this symptom? That seems
likely since I don't recall this problem when using the same antennas with
the IC-7600. I welcome any ideas or suggestions for where to look next.

Thanks,

Mike, K5MP

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John Oppenheimer

Re: K3 TVI on 40 meters only

Hi Mike,

Did you replace the uVerse modem recently? I had the same 40M problem
after replacing the modem. Google the issue, I believe you'll find
similar experiences.

John KN5L

On 08/25/2017 05:24 PM, Mike Pilgrim wrote:
> have TVI in my u-Verse TVs when using the
> K3 on 40 meters
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k6dgw

Re: K3 TVI on 40 meters only

In reply to this post by mjpilgrim

Does reducing the power change anything?

Is there an inherent issue in the K3 which might attribute to this symptom?

If there is, I'm pretty sure it's never been reported here before. We
have Uverse with 3 TV's via a wireless video bridge and one with a
FireStick, and no problems at all on any band at 100 W to an end-fed
wire on the back fence. I do turn a couple of touch lamps on and off
Navy-style on 80 and 160, but TV is fine.

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 8/25/2017 3:24 PM, Mike Pilgrim wrote:

> Recently replaced my ic-7600 with a new to me K3. I don't recall this issue
> when using the ic7600, but I now have TVI in my u-Verse TVs when using the
> K3 on 40 meters, primarily on CW, with diminishing evidence on SSB up to
> 7.2.50 but okay above that. The symptom is pixilation on the screen, then
> audio blanks out, and finally the set top box will completely lose signal.
> This occurs on two TV operating on wireless set top boxes, and two hardwired
> with CAT-5 cabling. I have tried on three separate end-fed long wires fed
> by coax through a 9:1 UNUN, two with feedline length of 100' and the third
> approximately 60 feet. I can operate satisfactorily on all bands from160 to
> 10 Meters with exception of 40 Meters on all three antennas. The K3 auto
> tuner indicates 1 bar of SWR with output power anywhere from 10 to 100
> Watts. I have also used an external ATU with same results. I have looked
> at everything I can think of, including terminating each antenna port with a
> dummy load, but to no avail. I've traced out all grounds and coax
> connections. Nothing helps. What might I be overlooking? Is there an
> inherent issue in the K3 which might attribute to this symptom? That seems
> likely since I don't recall this problem when using the same antennas with
> the IC-7600. I welcome any ideas or suggestions for where to look next.
>
> Thanks,
>
> Mike, K5MP

Jim Brown-10

Re: K3 TVI on 40 meters only

In reply to this post by mjpilgrim

Hi Mike,

I can't think of a mechanism whereby ANY ham rig could be the CAUSE of
interference to cable TV or DSL. On the other hand, there are MANY
mechanisms where CATV and DSL systems, equipment, and wiring ARE the
cause of interference to these systems, and there are several mechanisms
whereby these systems cause RF interference TO our ham bands.

I've seen many reports of UVerse being susceptible to ham transmitters.
Call UVerse and tell them to fix it.

73, Jim K9YC

On 8/25/2017 3:24 PM, Mike Pilgrim wrote:
> Recently replaced my ic-7600 with a new to me K3. I don't recall this issue
> when using the ic7600, but I now have TVI in my u-Verse TVs when using the
> K3 on 40 meters, primarily on CW, with diminishing evidence on SSB up to
> 7.2.50 but okay above that.

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k6mkf

Re: K3 TVI on 40 meters only

In reply to this post by k6dgw

I had TVI/internet lockups running a K3 into 80 & 160m wire antennas with U-verse. AT&T swapped out the modems numerous times, had three different models but no joy. Had their 'top techs' on the problem.

At the time, the 'net was filled with U-verse TVI issues. Switched to cable and no further problems.

Lots of folks are using U-verse without a TVI problem, but it never worked very well here.

-- Mike Flowers, K6MKF, NCDXC - "It's about DX!"

> On Aug 25, 2017, at 4:16 PM, Fred Jensen <[hidden email]> wrote:
>
> Does reducing the power change anything?
>
> Is there an inherent issue in the K3 which might attribute to this symptom?
>
> If there is, I'm pretty sure it's never been reported here before. We have Uverse with 3 TV's via a wireless video bridge and one with a FireStick, and no problems at all on any band at 100 W to an end-fed wire on the back fence. I do turn a couple of touch lamps on and off Navy-style on 80 and 160, but TV is fine.
>
> 73,
>
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
>
>> On 8/25/2017 3:24 PM, Mike Pilgrim wrote:
>> Recently replaced my ic-7600 with a new to me K3. I don't recall this issue
>> when using the ic7600, but I now have TVI in my u-Verse TVs when using the
>> K3 on 40 meters, primarily on CW, with diminishing evidence on SSB up to
>> 7.2.50 but okay above that. The symptom is pixilation on the screen, then
>> audio blanks out, and finally the set top box will completely lose signal.
>> This occurs on two TV operating on wireless set top boxes, and two hardwired
>> with CAT-5 cabling. I have tried on three separate end-fed long wires fed
>> by coax through a 9:1 UNUN, two with feedline length of 100' and the third
>> approximately 60 feet. I can operate satisfactorily on all bands from160 to
>> 10 Meters with exception of 40 Meters on all three antennas. The K3 auto
>> tuner indicates 1 bar of SWR with output power anywhere from 10 to 100
>> Watts. I have also used an external ATU with same results. I have looked
>> at everything I can think of, including terminating each antenna port with a
>> dummy load, but to no avail. I've traced out all grounds and coax
>> connections. Nothing helps. What might I be overlooking? Is there an
>> inherent issue in the K3 which might attribute to this symptom? That seems
>> likely since I don't recall this problem when using the same antennas with
>> the IC-7600. I welcome any ideas or suggestions for where to look next.
>>
>> Thanks,
>>
>> Mike, K5MP
>
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John Oppenheimer

Re: K3 TVI on 40 meters only

In reply to this post by Jim Brown-10

May find some information about the issue here:
http://adslm.dohrenburg.net/uverse/

It will depend on which VSDL frequency is being used by the modem. My
modem seemed to pick the high end of 40 meters most of the time.

John KN5L

On 08/25/2017 09:16 PM, Jim Brown wrote:
> I can't think of a mechanism whereby ANY ham rig could be the CAUSE of
> interference to cable TV or DSL.
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briancom

Re: K3 TVI on 40 meters only

John,

Very informative. I intend to throw it in the face of the next AT&T
salesman that comes knocking on my door. We get one every couple months.

It is especially true that they lie about now being pure fiber to the
house. I ask them how they installed fiber without having sent out a
machine to route it.

Not mentioned is the RFI that their modems can generate. Reading the
article confirms that it is almost a given-- especially for those with
overhead utilities.

73 de Brian/K3KO

On 8/26/2017 10:21 AM, John Oppenheimer wrote:

> May find some information about the issue here:
> http://adslm.dohrenburg.net/uverse/
>
> It will depend on which VSDL frequency is being used by the modem. My
> modem seemed to pick the high end of 40 meters most of the time.
>
> John KN5L
>
> On 08/25/2017 09:16 PM, Jim Brown wrote:
>> I can't think of a mechanism whereby ANY ham rig could be the CAUSE of
>> interference to cable TV or DSL.
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Elecraft mailing list

Re: K3 TVI on 40 meters only

FWIW: I also have Uverse and cannot use 80 or 40 (haven't tried 160). My research (reading posts from people who know what they are talking about) indicates it is due to subcarrier frequencies used by AT&T - they include frequencies in the 160-80-40m bands, ending around 9mHz. I can operate 30m (10mHz) just fine.
Here (Pearland, TX) it appears there is fiber to the neighborhood. However from a break-out to my house is POTS - twisted pair copper. Another ham stayed on AT&T until they used some sort of shielded cable (not sure what) instead of POTS and problem was solved.
I haven't gotten into AT&Ts face yet, but will. May very well switch to Comcast that use coax for the feeds.
I am certainly no expert, but have reached these conclusions from corresponding with hams who know a LOT more about this than I, and have experienced the same problem and reached the same conclusion.
73,JohnK5ENQ

From: brian <[hidden email]>To: [hidden email] >> 'Elecraft Reflector' <[hidden email]>Sent: Saturday, August 26, 2017, 7:16:08 AM CDTSubject: Re: [Elecraft] K3 TVI on 40 meters only
John,

Very informative. I intend to throw it in the face of the next AT&T
salesman that comes knocking on my door. We get one every couple months.

It is especially true that they lie about now being pure fiber to the
house. I ask them how they installed fiber without having sent out a
machine to route it.

Not mentioned is the RFI that their modems can generate. Reading the
article confirms that it is almost a given-- especially for those with
overhead utilities.

73 de Brian/K3KO

On 8/26/2017 10:21 AM, John Oppenheimer wrote:

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NK7Z

Re: K3 TVI on 40 meters only

In reply to this post by mjpilgrim

At least the issue is not important as it is only TV being disturbed,
not your ham radio receive! :)

73s and thanks,
Dave
NK7Z
http://www.nk7z.net

On 08/25/2017 03:24 PM, Mike Pilgrim wrote:

Lynn W. Taylor, WB6UUT-2

Re: K3 TVI on 40 meters only

In reply to this post by briancom

The industry term is FTTx.

What you're calling "pure" fiber is FTTH -- Fiber to the Home. Once it
gets to your house, it converts to copper, usually ethernet.

UVerse is FTTN -- Fiber to the Node (FTTC is Fiber to the Cabinet, same
thing).

It costs less because they don't have to run optical cable all the way
to your house, which may involve trenching or "special construction" of
some sort, it uses existing copper, and depending on the operator, gives
you the same speed you'd get with fiber.

... and at a lower cost.

That said, the short xDSL part isn't supposed to radiate.

I'm waiting for a gigabit FTTH project to reach me here. The ONT will
be in my office, but it'll be copper through the rest of the house.

<https://en.wikipedia.org/wiki/Fiber_to_the_x>

73 -- Lynn

On 8/26/2017 5:14 AM, brian wrote:
> It is especially true that they lie about now being pure fiber to the
> house.
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Jim Brown-10

Re: K3 TVI on 40 meters only

In reply to this post by briancom

This is an example of what I was talking about (quoted below) that I
can't think of any mechanism whereby ANY ham rig is the CAUSE of RFI,
and an example of several common mechanisms within those systems that
make them susceptible. Their equipment and systems SHOULD reject or
signals and fail to do so, thanks to failures in design, manufacturing,
and/or installation.

In other words, it is ALWAYS their fault.

73, Jim K9YC

On 8/26/2017 5:14 AM, brian wrote:

> John,
>
> Very informative. I intend to throw it in the face of the next AT&T
> salesman that comes knocking on my door. We get one every couple months.
>
> It is especially true that they lie about now being pure fiber to the
> house. I ask them how they installed fiber without having sent out a
> machine to route it.
>
> Not mentioned is the RFI that their modems can generate. Reading the
> article confirms that it is almost a given-- especially for those with
> overhead utilities.
>
> 73 de Brian/K3KO
>
>
>
> On 8/26/2017 10:21 AM, John Oppenheimer wrote:
>> May find some information about the issue here:
>> http://adslm.dohrenburg.net/uverse/
>>
>> It will depend on which VSDL frequency is being used by the modem. My
>> modem seemed to pick the high end of 40 meters most of the time.
>>
>> John KN5L
>>
>> On 08/25/2017 09:16 PM, Jim Brown wrote:
>>> I can't think of a mechanism whereby ANY ham rig could be the CAUSE of
>>> interference to cable TV or DSL.
>> ______________________________________________________________
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Bob McGraw - K4TAX

Re: K3 TVI on 40 meters only

I agree.   This mostly falls under the Part 15 rules where it says in
general; "they must accept interference but not cause interference,
etc". It boils down to a cost point.   In other words, they are using
the cheapest box that can be purchased to meet their requirements.
I've held their feet to the fire on the point to where they acknowledge
they have no choice in hardware or technical expertise that can or will
resolve the issue.

My other and older receiver worked fine with no issues until lightning
took it out. They replaced it with a new one which has issues. In
other words, "we would love to keep you as a customer but we can't fix
your problem".    The old receiver had an external connector for the RF
remote receiver. I removed the antenna, terminated the input and
switched the remote over to IR remote control.   The new receiver has a
built in antenna for remote control and thus it has a plastic box.
Even on IR remote the RF receiver is still active.   Projcet cost down
........ grrrrrr!

73

Bob, K4TAX

On 8/26/2017 11:23 AM, Jim Brown wrote:

> This is an example of what I was talking about (quoted below) that I
> can't think of any mechanism whereby ANY ham rig is the CAUSE of RFI,
> and an example of several common mechanisms within those systems that
> make them susceptible. Their equipment and systems SHOULD reject or
> signals and fail to do so, thanks to failures in design,
> manufacturing, and/or installation.
>
> In other words, it is ALWAYS their fault.
>
> 73, Jim K9YC
>
> On 8/26/2017 5:14 AM, brian wrote:
>> John,
>>
>> Very informative. I intend to throw it in the face of the next AT&T
>> salesman that comes knocking on my door. We get one every couple
>> months.
>>
>> It is especially true that they lie about now being pure fiber to the
>> house. I ask them how they installed fiber without having sent out a
>> machine to route it.
>>
>> Not mentioned is the RFI that their modems can generate. Reading the
>> article confirms that it is almost a given-- especially for those
>> with overhead utilities.
>>
>> 73 de Brian/K3KO
>>
>>
>>
>> On 8/26/2017 10:21 AM, John Oppenheimer wrote:
>>> May find some information about the issue here:
>>> http://adslm.dohrenburg.net/uverse/
>>>
>>> It will depend on which VSDL frequency is being used by the modem. My
>>> modem seemed to pick the high end of 40 meters most of the time.
>>>
>>> John KN5L
>>>
>>> On 08/25/2017 09:16 PM, Jim Brown wrote:
>>>> I can't think of a mechanism whereby ANY ham rig could be the CAUSE of
>>>> interference to cable TV or DSL.
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>>>
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>
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Jim Brown-10

Re: K3 TVI on 40 meters only

In reply to this post by Lynn W. Taylor, WB6UUT-2

On 8/26/2017 9:07 AM, Lynn W. Taylor, WB6UUT wrote:
> That said, the short xDSL part isn't supposed to radiate.

"Supposed" is the key word here. Radiation occurs due to several
mechanisms.

1) Poor circuit layout inside equipment that is also poorly shielded.
That wiring radiates.

2) Poor common mode isolation of wiring connected to equipment. On
paired cable, a low quality output transformer or poorly balanced output
stage puts common mode on the cable. On coax, a Pin One Problem puts
common mode on the cable. The cable radiates, just like any other
antenna. Power supply wiring is also a potential radiator, and the power
supply itself is often a noise source (if it's switch-mode).

3) Poor quality paired cable. Structured cable (CAT5/6/7) is, in
general, pretty high quality twisted pair, but quality also varies with
manufacturer. Belden, for example, builds its structured cable from
molded pairs, which makes their construction more uniform, which
minimizes radiation/reception of differential mode signals. By contrast,
parallel wire cables have lousy rejection (20-40 dB worse) and are prone
to radiation and reception of ANY interfering signal, from audio to VHF.

As an example of #3, zip cord, glorified or otherwise, is TERRIBLE
speaker cable, because it is a sitting duck for any audio or radio
frequency noise. When I lived in Chicago, solved a lot of RFI from
broadcast TV to hi-fi systems by replacing zip cord speaker cables with
twisted pair.

Sadly, most modern local telco wiring is either poor quality twisted
pair or not twisted at all. Using this wiring for DSL is an open door to
RFI.

These, and other issues related to RFI, including CATV and DSL systems,
are addressed in detail in several app notes and tutorials on my
website. k9yc.com/publish.htm

73, Jim K9YC

73, Jim K9YC

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Lynn W. Taylor, WB6UUT-2

Re: K3 TVI on 40 meters only

Went back to Mike's original message and read it more carefully.

First, he's reporting that his CW signal interferes with his TV, not the
other way around. It's not the VHDSL (probably) signal getting out, but
his 40 meter signal getting in.

UVerse is 100% digital, not analog. He describes how the picture breaks
up, and that's exactly what happens when there is a lot of packet loss.

I'd bet he'd notice internet problems at the same time as the TVI.

All of the TVs have the same issue at the same time, so it's not the
ethernet running around the house, or the WiFi, it's between the UVerse
box and the cabinet out on the street (the cabinet is fed by fiber).

Here's the fun bit, you mention "poor quality paired cable."

UVerse does not install a new drop. They take whatever wire happens to
be there, and use that. It's guaranteed to be CAT 3 or less. There
could be bridge taps, or multiple unterminated jacks in multiple rooms.

It could be RG-59, if there happens to be a coax run to where the
customer wants the router. It wouldn't be RG-59 all the way to the
cabinet. A mixed-up mess of wiring is not only possible, but likely.

73 -- Lynn

On 8/26/2017 9:59 AM, Jim Brown wrote:
> On 8/26/2017 9:07 AM, Lynn W. Taylor, WB6UUT wrote:
>> That said, the short xDSL part isn't supposed to radiate.
>
> "Supposed" is the key word here. Radiation occurs due to several
> mechanisms.

> 3) Poor quality paired cable.
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Jim Brown-10

Re: K3 TVI on 40 meters only

On 8/26/2017 10:58 AM, Lynn W. Taylor, WB6UUT wrote:
> First, he's reporting that his CW signal interferes with his TV, not
> the other way around. It's not the VHDSL (probably) signal getting
> out, but his 40 meter signal getting in.

Doesn't matter -- thanks to the principle of reciprocity, any passive
system that radiates will also receive, and all of that interface
(wiring, transformers, cable termination, Pin One Problem) is passive.
Take my post and substitute the word "receive" for "radiate."
Reciprocity is the principle that causes antenna gain and directivity to
be the same on receive as on transmit.

Further, electronics at both ends of these systems are noise sources,
and both are susceptible to interference, and both input and output
stages can be susceptible to interference. RFI often comes into audio
power amplifiers on their loudspeaker wiring, which couples back to the
input of the stage via the feedback network, where it is detected and
amplified.

Pin One Problems inject any current on cable shields onto the signal
common bus (traditionally called "ground"), where it gets injected into
gain stages at the whim of the PC layout artist, detected, and amplified
(or breaking up the digital signal). Study the tutorial material on my
website. Neil Muncy, ex-W3WJE (SK) published work documenting this in
1994. In bar conversation, he observed that most RFI issues are caused
by Pin One Problems. In 2003, I published research showing that
statement to be entirely correct with respect to audio gear. Those AES
Papers are on my website. There's also tutorial material that's easy to
read.

Because Pin One Problems are putting the interfering signal onto the
signal return bus (signal ground), there's no logic between which gain
stage detects it and the cable it came in on. The RF could be on an
output cable, or on the cable for input #3, but turning the gain for the
input or for mic #10 could cause the RFI to increase in level.

73, Jim K9YC

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Lynn W. Taylor, WB6UUT-2

Re: K3 TVI on 40 meters only

Since most DSL systems have multiple carriers, the only real distinction
between "in" and "out" is that there is no carrier near enough to
interfere with his receiver.

So, yeah, signals are radiating. It's just not generating Mike's complaint.

The main point I was trying to make is that the wiring will never be as
good as a straight CAT 5 run.

The installer is mostly looking from continuity from the DSLAM in the
cabinet/pedestal, through the B-Box to the TNI on the side of the house,
and from the TNI to the desired jack.

The pair from B-Box can run from one end of the feeder, through several
other B-Boxes. It can be tapped at the closest B-Box and run for
hundreds of feet with no termination.

From the TNI, the inside house wiring can have unterminated jacks in
every room.

To a phone company (and the FCC) everything on the customer's side of
the TNI belongs to the customer. Running good shielded twisted pair and
grounding the shield as best you can at both ends might help, with the
rest of the house jacks disconnected at the TNI.

That assumes they're not using a POTS phone. I haven't had one for years.

73 -- Lynn

On 8/26/2017 11:29 AM, Jim Brown wrote:

> On 8/26/2017 10:58 AM, Lynn W. Taylor, WB6UUT wrote:
>> First, he's reporting that his CW signal interferes with his TV, not
>> the other way around. It's not the VHDSL (probably) signal getting
>> out, but his 40 meter signal getting in.
>
> Doesn't matter -- thanks to the principle of reciprocity, any passive
> system that radiates will also receive, and all of that interface
> (wiring, transformers, cable termination, Pin One Problem) is passive.
> Take my post and substitute the word "receive" for "radiate."
> Reciprocity is the principle that causes antenna gain and directivity to
> be the same on receive as on transmit.
>
> Further, electronics at both ends of these systems are noise sources,
> and both are susceptible to interference, and both input and output
> stages can be susceptible to interference. RFI often comes into audio
> power amplifiers on their loudspeaker wiring, which couples back to the
> input of the stage via the feedback network, where it is detected and
> amplified.
>
> Pin One Problems inject any current on cable shields onto the signal
> common bus (traditionally called "ground"), where it gets injected into
> gain stages at the whim of the PC layout artist, detected, and amplified
> (or breaking up the digital signal). Study the tutorial material on my
> website. Neil Muncy, ex-W3WJE (SK) published work documenting this in
> 1994. In bar conversation, he observed that most RFI issues are caused
> by Pin One Problems. In 2003, I published research showing that
> statement to be entirely correct with respect to audio gear. Those AES
> Papers are on my website. There's also tutorial material that's easy to
> read.
>
> Because Pin One Problems are putting the interfering signal onto the
> signal return bus (signal ground), there's no logic between which gain
> stage detects it and the cable it came in on. The RF could be on an
> output cable, or on the cable for input #3, but turning the gain for the
> input or for mic #10 could cause the RFI to increase in level.
>
> 73, Jim K9YC
>
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Phil Kane-2

Re: K3 TVI on 40 meters only

In reply to this post by Jim Brown-10

On 8/26/2017 9:23 AM, Jim Brown wrote:

> In other words, it is ALWAYS their fault.

Until the rig starts outputting spurious signals. I'm still of the
generation when low-pass filters were not all that common, ditto for
transmitter shielding and bypassing.

Never say never when it comes to the Tennessee Valley Indians.

73 de K2ASP - Phil Kane
Elecraft K2/100 s/n 5402

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon
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