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Re: Anyone using a DXE NCC-1 with K3?

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NH7RO

Re: Anyone using a DXE NCC-1 with K3?

Am contemplating a purchase of a DXE NCC-1 receiving antenna/noise phasing unit very soon (tomorrow, actually---so I will have it in time for the WPX next weekend) for use with my K3/P3/KPA500 and was wondering if anyone else in the group uses one and how they have it configured. Apparently I will either need to run it via my RX antenna jack or else with a sequencing unit (or RTR-1A controller that DXE also sells) if I want to run it inline with my main antennas.

My main usage will be for the reduction of RFI that I am often subject to here in our condo complex (plasma or LCD TVs, wall warts and other electronic RF garbage producers nearby). I currently use an old JPS ANC-4 with its attached noise receiving whip that works fairly well---but could still be much better. (I don't plan to buy the active antennas that DXE also sells with or without the NCC-1; at least not for any foreseeable future).

I also use my Elecraft PR6 6M preamp affixed via the XVTR or RX antenna BNC jacks and am wondering if I can run the NCC-1 through it with or without the PR6 being on (I have it wired so that the PR6 activates only when I am on 6M, IIRC)---but I am getting older these days and am more easily confused/dyslexic when it comes to IN/OUT jacks than I used to. Will it be fairly easy to run both together or will it require removing the PR6 if I want to run the NCC-1 through the RX ports?

Any user comments or thoughts on the subject will be appreciated; I have seen a few YouTube videos on the NCC-1 and it looks like it can be very effective on QRN coming from one particular source (like my ANC-4 but even noticeably better). It certainly will be fun to see the noise disappear or fall dramatically on my P3, too!

73, Jeff, NH7RO

K3/P3/KPA500

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NH7RO

Re: Anyone using a DXE NCC-1 with K3?

Hank;

Many thanks for your two lengthy and detailed replies although I am a bit dismayed at your unlucky results with the NCC-1. Not really expecting to hear something like that so now I am scratching my head wondering whether or not to jump in anyway or hold off another year if/when the improved model hits the shelves.

Some of what you wrote is a bit over my head but I got the general gist of it; obviously there is still room for improvement (perhaps in the quality control department if there is such a broad range between various units?). Perhaps you got the one and only Edsel of the lot, though considering that most every other review I've read has been overwhelmingly positive. I thought the YouTube demonstrations were compelling; especially the one with two strong BCB stations on the same frequency---with either one being able to be nulled out almost completely. Night and day!

I'm not sure whether my simple condo antenna setup will be a better candidate or not compared to yours and others who have DXE noise antennas set up far away from their shacks and TX antenna(s). Right now I'm using a variable-length inverted U dipole (10-12-15-17-20M) with the top horizontal portion/feedpoint only about 20 feet above ground. It is suspended by some fiberglass poles mounted at the top of a wooden beam over our front porch balcony and I am able to work plenty of DX with the help of Ion, the Propagation God and the 650 watts that my KPA500 provides. While far from ideal at least I am able to enjoy the hobby much more and utilize my entire K-line again since departing KH6 (DX paradise) three years ago.

As I mentioned before, my noise antenna so far is only the three or four foot whip atop my ANC-4 and most of the time it works from almost fair to very good---depending on various factors and the type of noise involved (usually next door or downstairs TV). My noise antenna is only about 20 feet away from my balcony dipole (whose ends are hanging down so it has both vertical and horizontal components---probably helping my signals get beyond the surrounding obstacles so close to me here.

I am also just about to finish building my first STL (magnetic loop antenna) for 10-20M which are the bands I operate 98% of the time, too. I have been taking my time constructing it carefully so that it should perform at optimum levels for what it is (I rolled a 9.5' copper pipe 1.125" OD into a circle and it has only two silver brazed connections for the vacuum variable capacitor clamps).

This loop will probably end up replacing the inverted U and also be less susceptible to the RFI that I am now experiencing---but I want to go the extra mile with my station anyway. I plan to roll additional loops (recently purchased a Hulk tubing roller that works very well) so my noise antenna will follow in my TX antenna's "footsteps" soon. I can put that 2nd (noise) loop out on our cramped back balcony and hope for the best. I don't really know much about how the coupling (or lack of) factors into all of this but it will be interesting to see how two STLs will perform with an NCC-1 and also the diversity feature in my K3. ( I also will upgrade both main and sub synthesizers, too later this year after every little bug is worked out and the backlog of orders gets caught up).

One last thing I'll mention before I QRT and make a run to Home Depot (building a wooden stand for my loop); most of my noise is up on the higher bands---unlike your 160M operation that you used the NCC-1 for---so maybe I will enjoy better results for this particular usage?

Anyway, I think I will go ahead and take the plunge today and try it out despite your helpful warning---curiosity might be getting the better of me... I already have some gold-plated BNCs and RCA phono cables that I can rig up so I will try it hooked into the KXV3A ports (I'll just remove the PR6 as nothing's happening on 6M now anyway) as well as make a cable for the PTT line.

I hope to get this up and running by the upcoming WPX this weekend---either way, I will follow up with my impressions here thereafter in case other K3 owners are considering adding one of these to their ham shack.

Thanks again for taking the time to explain your experience, Hank and if mine doesn't cut the mustard I can't say you didn't try to warn me, hi hi!

73 to you and the Elecraft forum for listening to my rambling,

Jeff, NH7RO

> From: [hidden email]
> To: [hidden email]
> Subject: Re: [Elecraft] Anyone using a DXE NCC-1 with K3?
> Date: Sun, 22 Mar 2015 16:32:46 -0700
>
> I see I did not address how it was connected - Like you , all the possible
> configurations with the KXV3A and aux ant input to sub rx give you a
> dizzying set of choices.
>
> In my case I wanted to null against my TX antenna. (the KE7X book if you
> have it is a huge help in picking the configuration )
>
> Couple notes - the inputs and outputs are in parallel with a F and RCA jack
> provided- watch any el cheapo BNC to RCA or BNC to F adapters . I finally
> made up RG58 cables with BNC one end and RCA other end.
>
> The NCC has a KEY input that kills B+ to a remote antenna and disables the
> NCC in tx. it is RCA.
>
> I had built my own box to short the rx line to the K3 to ground and also to
> open the line - I depend on the K3 10 msc delay from key down to RF out for
> sequencing . (I did the both opening and the shorting with some nice little
> DPDT relays from All Electronics that have gold flashed contacts for dry
> circuits. My little box also drives the key line on an ALPHA 8410 when I am
> using it instead of the KPA/KAT. Also gives DC isolation so all the
> assorted key lines don't try to talk to each other .
>
> OK - now to the K3/KXV#a -- First I do not have a 10/6 M preamp to worry
> with - so her si hwo I did itv .
>
> Tx ant against the active noise antenna
>
> My TX ant is on ANT1.
>
> NCC1 RX out goes to KXV3A "IN"
>
> NCC! IInput "A" goes the KXV3A "OUT"
>
> NCC1 Input "B" goes to the active antenna line from my box. (forgot to
> mention that I used the little wall wart and DC inserter than came with the
> active antenna so I did not have to modify my little box to take the short
> off )
> All this is pretty similar to the NCC manual Fig 3 on page 10.
>
> When using something other than a little whip like you are with the ANC -
> be sure you KNOW what the coupling is to the noise ant. I have a VNA2180 so
> can measure coupling and typical coupling to my 160 tuned loop is -25 dB and
> about same when I look at most any other combination of things . At 1500
> watt TX on 160 that means about 5 watts coming back the loop ant line .
>
> Hope that helps -
>
> 73 Hank K7Hp
>
>
> -----Original Message-----
> From: Jeff Cathrow
> Sent: Sunday, March 22, 2015 2:04 PM
> To: Elecraft Digest
> Subject: Re: [Elecraft] Anyone using a DXE NCC-1 with K3?
>
> Am contemplating a purchase of a DXE NCC-1 receiving antenna/noise phasing
> unit very soon (tomorrow, actually---so I will have it in time for the WPX
> next weekend) for use with my K3/P3/KPA500 and was wondering if anyone else
> in the group uses one and how they have it configured. Apparently I will
> either need to run it via my RX antenna jack or else with a sequencing unit
> (or RTR-1A controller that DXE also sells) if I want to run it inline with
> my main antennas.
>
> My main usage will be for the reduction of RFI that I am often subject to
> here in our condo complex (plasma or LCD TVs, wall warts and other
> electronic RF garbage producers nearby). I currently use an old JPS ANC-4
> with its attached noise receiving whip that works fairly well---but could
> still be much better. (I don't plan to buy the active antennas that DXE
> also sells with or without the NCC-1; at least not for any foreseeable
> future).
>
> I also use my Elecraft PR6 6M preamp affixed via the XVTR or RX antenna BNC
> jacks and am wondering if I can run the NCC-1 through it with or without the
> PR6 being on (I have it wired so that the PR6 activates only when I am on
> 6M, IIRC)---but I am getting older these days and am more easily
> confused/dyslexic when it comes to IN/OUT jacks than I used to. Will it be
> fairly easy to run both together or will it require removing the PR6 if I
> want to run the NCC-1 through the RX ports?
>
> Any user comments or thoughts on the subject will be appreciated; I have
> seen a few YouTube videos on the NCC-1 and it looks like it can be very
> effective on QRN coming from one particular source (like my ANC-4 but even
> noticeably better). It certainly will be fun to see the noise disappear or
> fall dramatically on my P3, too!
>
> 73, Jeff, NH7RO
>
> K3/P3/KPA500
>
>
>
>
>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: 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]
>

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Jim Brown-10

Re: Anyone using a DXE NCC-1 with K3?

On Mon,3/23/2015 9:29 AM, Jeff Cathrow wrote:
> Not really expecting to hear something like that so now I am scratching my head wondering whether or not to jump in anyway or hold off another year if/when the improved model hits the shelves.

The limitations on what can be achieved with noise cancellation units
like this is NOT inadequacy of the design of the box. It is entirely
dependent on the noise sources, their locations, your main antennas, and
what you can do for sense antennas. You can wait forever for "an
improved model," or you can study how antennas work and how signal
cancellation works. I suggest the latter course. You may also benefit
from studying k9yc.com/RFI-Ham.pdf, which is a tutorial about RF noise
and how to reduce it, among other things.

73, Jim K9YC
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NH7RO

Re: Anyone using a DXE NCC-1 with K3?

Hank; I'm truly very sorry if my reply to you ended up with your initial response posted on the reflector; I have a hard time figuring out these mailing lists and where everything is coming from and going to and it probably was all my fault (if it somehow got posted with my reply; not sure if it did or not). Anyway, my apologies to all concerned.

I hope it is all clear to everyone now and that the NCC-1 discussion can continue further without much distraction.

When I ordered the NCC-1 a little while ago DXE said that it would be a whole new design that they would be coming out with---not a modification of the NCC-1 per se, FWIW. I decided to try one out this week as I otherwise might be "waiting for Godot..." (indefinitely).

I also ordered a "Receiver Guard 5000" to put into the noise antenna line which protects the receiver further while transmitting QRO as I often do; a bit of extra insurance for my precious K3.

73, Jeff, NH7RO

> From: [hidden email]
> To: [hidden email]
> CC: [hidden email]
> Subject: Re: [Elecraft] Anyone using a DXE NCC-1 with K3?
> Date: Mon, 23 Mar 2015 12:07:07 -0700
>
>
>
> Jim - I am really PO'ed that a private message to this guy is now on the
> Elecraft reflector - I am even more PO'ed that you chose to infer that I
> don't know what the hell I am doing, and especially on an open reflector .
>
> For your information apparently you do not have the whole story, unless Jeff
> sent you my original message. You do not even know what the box I received
> was doing . And that DXE confirmed the box was unusable as received.
> Further I emailed with the original designer of the box and he also agreed
> that it was unusable as received- and had suggestions for changes that I
> could do to make the amplitude control more usable.The inference was that
> the original design is not being built as originally designed. I do not
> elect to pay $600 for something I am going to start modifying the day I
> receive it . I FULLY understand everything in your first sentence- and went
> over all this at length with DXE.
>
> The "improved model" in fact is to address the issues I found - smaller
> amplitude steps in the two signal channels , and fixing the amplitude
> control so it is not +/- 0.5 dB for 2/3 of its rotation and then the 0.5 to
> 10 dB is in next 1/8 inch of rotation at either end . I will say the
> amplitude variation with phase change is excellent - even better than the 1
> dB they quote - so very little iteration to get to a null
>
> Hank K7HP
>
> Here is what I sent to Jeff .
>
> Jeff - I just went thru a pretty disappointing experience with a NCC1 -- and
> I even bought the vertical active antenna to use to phase against my TX
> antenna.
> The NCC1 has gone back to DXEngineering - I played with it for about a
> week – never accomplished a damn thing with it – finally put a BNC T and 6
> db pads in each arm to the two inputs –and a external step atten in one
> arm. It turned out the amplitude balance control range on the unit I had
> was +/- a half dB for 200 degrees of rotation – so the rest of a 10 dB step
> was compressed into a tiny movement at either end of rotation.Plus it
> appeared to be just attenuating both signals at that point – not really a
> null. So back it went – with my data - they confirmed it was like that –and
> said the “best ones” were maybe 2 to 3 dB for that half dB range I see and
> they would see if they could find one like that – 2 weeks and no find.
>
> They say two things – first it was really designed to work with two
> identical antennas and “hundreds of folks” have no problem when using
> identical antennas .-like their active antennas. Second they have a
> redesigned unit coming out some time in next 6 months to year (undefined)
> that will have smaller attenuator steps and less “expanded” amplitude range
> around the zero point . They suggested a "fix" that I could put a step
> attenuator in series with one side to get the two amplitudes in that 0.5 dB
> range . I don’t have a step atten with 0.5 dB steps smallest is 1 dB - guess
> I could make one with a carbon pot that was small increments .
>
> I emailed with Tom W8JI and he suggested some changes I could make to fix
> the amplitude control – but said he was in middle of a paying job , had not
> looked at that design for years , and would get back to me in a couple weeks
> . I thanked him but don’t bother I am going to just return it .Somehow I don’t
> see paying $600 for something I am going to have to modify. I get the
> impression they have screwed with his original design, I never did get any
> warm feeling they really knew what the hell they were talking about – sent
> them the test setup and what to do and what I was seeing – they confirmed it
> after a little over a week – but never called back or emailed like they said
> they would and there was always some excuse – so yesterday I said just give
> me credit and I will wait and see what the new unit looks like,
>
> Now having said all that , I will say the phase adjustment is VERY good ,
> very little gain change with phase change so the null does not require much
> chasing . I do think it will be a very nice unit with the redesign - and
> will very likely give it another shot when that comes out .
>
> Every thing I am talking about was on 160 meters - I never could get any
> improvement whatsoever over using my home brew 160 meter 24 foot
> circumference loop .
>
> Since your ANC4 is working MAYBE your noise and other antenna are close
> enough the NCC might balance - but ....
>
> I do not like bad mouthing DXE stuff , but I earned my living in RF for 50
> years and and reasonably well equipped with test equipment and they
> confirmed
> my measurements .
>
> Soi there are my 2 cents worth - hopefully you will get responses from guys
> who got "good ones"
> l.
>
>
>
> XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
>
>
> The limitations on what can be achieved with noise cancellation units like
> this is NOT inadequacy of the design of the box. It is entirely
> dependent on the noise sources, their locations, your main antennas, and
> what you can do for sense antennas. You can wait forever for "an
> improved model," or you can study how antennas work and how signal
> cancellation works. I suggest the latter course. You may also benefit
> from studying k9yc.com/RFI-Ham.pdf, which is a tutorial about RF noise
> and how to reduce it, among other things.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Post: mailto:[hidden email]
>
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> Message delivered to [hidden email]
>

Robert Cunnings

Re: Anyone using a DXE NCC-1 with K3?

In reply to this post by NH7RO

I have local noise problems which come and go depending on time of day,
day of week etc. I didn't like the idea of having a noise cancelling
device in the high power transmit path, so picked up a DX Engineering
NCC-1 which is perfect for use with my K3, inserted between the antenna
OUT and antenna IN jacks. I have a horizontally polarized loop which I use
as the RX antenna on the K3 when I need to fight noise. A vertical doublet
antenna is used as the transmit antenna, which serves as the noise sense
antenna in receive when the NCC-1 is active.

To do this, the loop antenna goes to antenna port A on the NCC-1
(receive antenna input), K3 antenna OUT (from the transmit antenna)
goes to antenna port B on the NCC-1 (noise antenna input) and the
output of the NCC-1 goes to the K3 antenna IN. K3 KEY OUT goes to NCC-1
T/R CTRL to put it in bypass when the K3 is keyed.

Now I have 3 choices:

1. If I then select the RX antenna on the K3, the NCC-1 is inserted and I
use the quieter loop antenna for receive while nulling noise with the
NCC-1 controls. 2. If I don't select the RX antenna on the K3, the NCC-1
is bypassed, and the transmit antenna is used for receive. 3. If I select
the RX antenna on the K3, but turn the NCC-1 OFF, then I receive on the
loop antenna, but the signal passes straight through the NCC-1 from
antenna port A to the output without modification (sometimes that's all
that's needed, it's much quieter than the vertical when it comes to the
nearby noise pollution sources).

The NCC-1 can provide a very deep null on the receive loop antenna for
vertically polarized noise which is "heard" better on the vertical. The
trick is to correctly balance the levels of the two antenna inputs on the
NCC-1. The balance and phase controls are very precise and repeatable, and
the phase control has a wide range. Having the P3 to look at helps in
identifying the noise and finding what can be a very sharp (but deep)
null.

There are complications. One is that when the NCC-1 is active I need to
disable full QSK on the K3 in CW mode so that the internal bypass relay in
the NCC-1 doesn't make a lot of noise as it follows the keying.

The other involves antenna tuners. I use a KAT500, and if a frequency
change causes it to recall new L and C settings then the NCC-1 phase
setting may need to be touched up because the phase of the noise signal
from the transmit antenna is changed (and the NCC-1 null can be very sharp
indeed).

But for me the benefits have far outweighed the costs.

Bob NW8L

On Sun, 22 Mar 2015, Jeff Cathrow wrote:

> Am contemplating a purchase of a DXE NCC-1 receiving antenna/noise phasing unit very soon (tomorrow, actually---so I will have it in time for the WPX next weekend) for use with my K3/P3/KPA500 and was wondering if anyone else in the group uses one and how they have it configured. Apparently I will either need to run it via my RX antenna jack or else with a sequencing unit (or RTR-1A controller that DXE also sells) if I want to run it inline with my main antennas.
>
> My main usage will be for the reduction of RFI that I am often subject to here in our condo complex (plasma or LCD TVs, wall warts and other electronic RF garbage producers nearby). I currently use an old JPS ANC-4 with its attached noise receiving whip that works fairly well---but could still be much better. (I don't plan to buy the active antennas that DXE also sells with or without the NCC-1; at least not for any foreseeable future).
>
> I also use my Elecraft PR6 6M preamp affixed via the XVTR or RX antenna BNC jacks and am wondering if I can run the NCC-1 through it with or without the PR6 being on (I have it wired so that the PR6 activates only when I am on 6M, IIRC)---but I am getting older these days and am more easily confused/dyslexic when it comes to IN/OUT jacks than I used to. Will it be fairly easy to run both together or will it require removing the PR6 if I want to run the NCC-1 through the RX ports?
>
> Any user comments or thoughts on the subject will be appreciated; I have seen a few YouTube videos on the NCC-1 and it looks like it can be very effective on QRN coming from one particular source (like my ANC-4 but even noticeably better). It certainly will be fun to see the noise disappear or fall dramatically on my P3, too!
>
> 73, Jeff, NH7RO
>
> K3/P3/KPA500
>
>
>
>
>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: 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]
>

NH7RO

Re: Anyone using a DXE NCC-1 with K3?

Thanks, Bob, for your concise description of how you use your NCC-1 with your K3---it is very helpful to me as I am almost confused by all the choices of configuration---a lot more ways to set it up than I thought.

My situation is that I plan (at least initially) to use only 1 un-amplified noise antenna into the B input of the NCC-1 along with a DXE Receiver Guard (high RF limiter to protect both rig and NCC-1 during xmit) since my transmit antenna is a mere 20 feet or so from my operating desk.

I'll see how that works and then add a second noise/receive antenna to the A input. Both noise antennas will be simple vertical wires or short indoor dipoles here in our small rented condo; maybe one will be longer and bent around corners and windows out to the back balcony. I can't really put the noise antennas outside the shack as our windows and back balcony are screened in with fiberglass in a frame that the owner installed that I would be very reluctant to mess with. At least my xmit antenna is outdoors and a bit higher up. While I am on a multiband inverted U dipole now I am almost finished building a really fine magnetic loop as mentioned in my earlier post; it will probably be an improvement over the inv. U to start with and its high Q will undoubtedly help with the RFI hash before I put the NCC-1 to work, too (fingers crossed). Ultimately I will also employ a second and third STL (mag loop) as noise/receive antennas for diversity reception and better noise nulli
ng once I am able to put them in place. But that may a lot more tricky than I imagine if I will have to constantly re-tune them as well as the main transmitting loop---so we'll see how it goes with the simpler vertical wires first.

I got the big box from DXE yesterday and lo and behold, the NCC-1 is almost the same size and heft as my loaded K3/100! I still need to make up some RG58 jumpers so I can hook it all up but I will try to do so tomorrow during the WPX (been delayed with other stuff all week so am not ready to get it up and running just yet). I want to make sure I hook it up correctly and your reply has certainly given me a clearer picture of how to accomplish that now.

Since my noise antenna(s) will not be active I will set the internal dip switch to external power for the noise antennas and keep power from being applied to that port completely.

Also, since I run QRO most of the time (and my STL will be set up to handle 650 watts from my KPA) I will make sure that the TX control line is plugged into the K3's PTT jack and that the BNC receiver Guard is correctly placed ahead of both the NCC-1 and K3 RX input.

I considered spring for one of DXE's sequencers but as I am already over budget on this shebang I decided to go with the less expensive Receiver Guard initially. Hopefully this will suffice with no further gear inline required---but if anyone here thinks that is still unwise please speak up ASAP* as I want to try to get this going sometime Saturday during the WPX---I'll need it with the current noise on most of the bands here.

(*If I AM running the risk of damaging my receiver/NCC I will not use it at all during QRO operation until I can eventually get a sequencer in line, too)

Fingers crossed and hoping that I will be OK with what I have now so I can start enjoying this fine piece of gear right away.

Thank you again, Bob for helping me out; it is very much appreciated. I can't wait to watch the noise diminish on my P3, too.

Vy 73,

Jeff, NH7RO

K3 #5528 P3 #1397 KPA500 #0250

> Date: Fri, 27 Mar 2015 00:11:03 -0600
> From: [hidden email]
> To: [hidden email]
> CC: [hidden email]
> Subject: Re: [Elecraft] Anyone using a DXE NCC-1 with K3?
>
>
> I have local noise problems which come and go depending on time of day,
> day of week etc. I didn't like the idea of having a noise cancelling
> device in the high power transmit path, so picked up a DX Engineering
> NCC-1 which is perfect for use with my K3, inserted between the antenna
> OUT and antenna IN jacks. I have a horizontally polarized loop which I use
> as the RX antenna on the K3 when I need to fight noise. A vertical doublet
> antenna is used as the transmit antenna, which serves as the noise sense
> antenna in receive when the NCC-1 is active.
>
> To do this, the loop antenna goes to antenna port A on the NCC-1
> (receive antenna input), K3 antenna OUT (from the transmit antenna)
> goes to antenna port B on the NCC-1 (noise antenna input) and the
> output of the NCC-1 goes to the K3 antenna IN. K3 KEY OUT goes to NCC-1
> T/R CTRL to put it in bypass when the K3 is keyed.
>
> Now I have 3 choices:
>
> 1. If I then select the RX antenna on the K3, the NCC-1 is inserted and I
> use the quieter loop antenna for receive while nulling noise with the
> NCC-1 controls. 2. If I don't select the RX antenna on the K3, the NCC-1
> is bypassed, and the transmit antenna is used for receive. 3. If I select
> the RX antenna on the K3, but turn the NCC-1 OFF, then I receive on the
> loop antenna, but the signal passes straight through the NCC-1 from
> antenna port A to the output without modification (sometimes that's all
> that's needed, it's much quieter than the vertical when it comes to the
> nearby noise pollution sources).
>
> The NCC-1 can provide a very deep null on the receive loop antenna for
> vertically polarized noise which is "heard" better on the vertical. The
> trick is to correctly balance the levels of the two antenna inputs on the
> NCC-1. The balance and phase controls are very precise and repeatable, and
> the phase control has a wide range. Having the P3 to look at helps in
> identifying the noise and finding what can be a very sharp (but deep)
> null.
>
> There are complications. One is that when the NCC-1 is active I need to
> disable full QSK on the K3 in CW mode so that the internal bypass relay in
> the NCC-1 doesn't make a lot of noise as it follows the keying.
>
> The other involves antenna tuners. I use a KAT500, and if a frequency
> change causes it to recall new L and C settings then the NCC-1 phase
> setting may need to be touched up because the phase of the noise signal
> from the transmit antenna is changed (and the NCC-1 null can be very sharp
> indeed).
>
> But for me the benefits have far outweighed the costs.
>
> Bob NW8L
>
> On Sun, 22 Mar 2015, Jeff Cathrow wrote:
>
> > Am contemplating a purchase of a DXE NCC-1 receiving antenna/noise phasing unit very soon (tomorrow, actually---so I will have it in time for the WPX next weekend) for use with my K3/P3/KPA500 and was wondering if anyone else in the group uses one and how they have it configured. Apparently I will either need to run it via my RX antenna jack or else with a sequencing unit (or RTR-1A controller that DXE also sells) if I want to run it inline with my main antennas.
> >
> > My main usage will be for the reduction of RFI that I am often subject to here in our condo complex (plasma or LCD TVs, wall warts and other electronic RF garbage producers nearby). I currently use an old JPS ANC-4 with its attached noise receiving whip that works fairly well---but could still be much better. (I don't plan to buy the active antennas that DXE also sells with or without the NCC-1; at least not for any foreseeable future).
> >
> > I also use my Elecraft PR6 6M preamp affixed via the XVTR or RX antenna BNC jacks and am wondering if I can run the NCC-1 through it with or without the PR6 being on (I have it wired so that the PR6 activates only when I am on 6M, IIRC)---but I am getting older these days and am more easily confused/dyslexic when it comes to IN/OUT jacks than I used to. Will it be fairly easy to run both together or will it require removing the PR6 if I want to run the NCC-1 through the RX ports?
> >
> > Any user comments or thoughts on the subject will be appreciated; I have seen a few YouTube videos on the NCC-1 and it looks like it can be very effective on QRN coming from one particular source (like my ANC-4 but even noticeably better). It certainly will be fun to see the noise disappear or fall dramatically on my P3, too!
> >
> > 73, Jeff, NH7RO
> >
> > K3/P3/KPA500
> >
> >
> >
> >
> >
> >
> >
> >
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