New Accessory for Flex6700 - Cognitive Processor Bus Interface

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Press Release - for immediate publication

K6TU announces Cognitive Processor Bus Interface for the FlexRadio 6700

Woodside, California:  November 18th, 2014:  K6TU is proud to announce the immediate availability of the Cognitive Processor Bus Interface (CPBI) for the FlexRadio 6700.  The CPBI enables faster QSO rates in contests by continually adapting to shifting band conditions by interfacing to the K6TU WetWare Neural Processor.  Signals are spatially separated instantly in the Neural Processor allowing quicker extraction of callsigns and contest exchange data.

The CPBI and Neural Processor also aid pile up management by separating multiple calling stations clearly and quickly, cutting down the number of repeats or fills required to extract a complete callsign.

Designed for the discerning contesters and expert operator, the CPBI improves contest rate, reduces fatigue, increases motivation and moves the fun factor into warp drive!

Further information can be found on the K6TU blog.

For pricing information, please contact K6TU directly.
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Stu Phillips - K6TU, Elmer

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Posted 4 years ago

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Jon W1JDB

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I tried reading your blog with both eyes but my buss must have been too wet...

Great reading with one eye though :-)


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George O'Brien, AB4FH

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Hi Stu,

I love the iPad K6TU app, but wonder if I should wait until the 1st of April for you new offering?

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Stu Phillips - K6TU, Elmer

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No, no!  This is REAL and not an April 1st gag!

Its shipping NOW!
Stu K6TU
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George O'Brien, AB4FH

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Okay, Stu, I've read the blog.  I chose the 6700 because it has a second receiver.  The TenTec Orion II that I am selling also has a second receiver.  I use a SteppIr DB18 and a Pixeloop antenna in diversity mode.  I use an inverted L antenna and the Pixeloop mag loop antenna on 160 meters. This makes a BIG difference on top band.  Please tell me more about your software and how it enhances the effect?
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Stu Phillips - K6TU, Elmer

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George,

No software required!  Everything you need is already in V1.3.8 of SSDR - just adjust the controls a little and the effects I've described in my blog post will come dancing into your hearing!

I think THE huge advantage with the 6700 is that the two SCU's are phase synchronous so with some good separation between the two antennas, you can get amazing reception!

Stu K6TU
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George O'Brien, AB4FH

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You are right about the importance of phase coherence.  I had to work with the Orion to adjust the phase between the two receivers, since, unlike the K3, the LO's are not phase lock looped. Three cheers for DIV mode on the 6700!
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George O'Brien, AB4FH

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Hey Stu,

One last comment...I've read that this psychoacoustic phenomenon creates a sound stage in our minds, not only left-to-right one, but front-to-back as well.  It's almost an acoustic hologram, isn't it?  I highly recommend everyone to try it if they can.

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Stu Phillips - K6TU, Elmer

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George,

That was exactly the effect - especially in the pile up case.  Until you experience it, its hard to describe but the pile up was spread out on the mental sound stage and it was a slum dunk to get the full call first time of one of the callers.

I have have some additional integration work to do with my remote rotor control for the loop... I want to be able have the option to automatically slave the azimuth of the loop to that of the Yagi.  I'm also wondering about phasing two loops together at 90 degrees to each other to change the cardioid pattern to just a single lobe...

It's all about rate!
Stu K6TU
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DrTeeth

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Sounds like an invite to a party at Stu's for a demo, hi hi.
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Ken - NM9P, Elmer

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Gee, Stu, it is enough to make us lowly 6500 owners jealous!  
Seriously.  This feature, and 2 Meter coverage are the only regrets I have about not being able to afford the 6700.  

It would be interesting to hear a recording someday.  Perhaps before the next contest you can set up Audacity and simply hit "record" when you are in the middle of a good example session.  Then record about ten minutes and stop.  You can save and export it during a break or after the contest is over.

I bet it would help sell some more 6700's!

Ken - NM9P.

BTW.  I didn't play in this contest because I had too many meetings that weekend.
I hope to be up and on the ball for the three big 160 contests.  I need CA, HI, AK & UT for 160 WAS from Indiana!
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Stu Phillips - K6TU, Elmer

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I will give it a shot! 
Stu K6TU
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George O'Brien, AB4FH

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If you do listen to Stu's recording, it must be in stereo on headphones.  Speakers will not work due to mixing the sounds and therefore the phase delays between the left and right channels.

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Andrew Russell

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I did worry that I might be jealous of the 6700 for diversity, but another GPS locked 6500 at a diverse location might be better. You use mine and I use yours.
For the 6700 I wonder if an adjustable time delay between the two receivers might enhance the spacial perception and gain pattern.

Andrew VK5CV
(Edited)
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Ken - NM9P, Elmer

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Interesting idea... But I wasn't able to get the GPS option. Another $600 that I didn't have at the time. ... Now if I could find a really cheap, but stable, 10 MHz reference......I could lock my 6500 and 1500 together. That would be nice!
(Edited)
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Andrew Russell

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Ken,
I do have my 1500 on the 10MHz output of the GPS unit in the 6500. Havn't tried both at once yet. Different latencies and frequency errors though.
I do have an MFJ analogue noise reducing phasing box and that worked vey well on the 1500 with a noise antenna, a 40m sloper 40m from the 160m inverted L. The panadapter makes adjustment for narrow band signals a snip.
The other noise source of use may be the common mode on the feedline. Diverse in terms of wanted and unwanted but not space. A bit of a challenge for transmitting though. I really wish I had room for a shared apex loop array but the block is 150 x 50ft.
I do have a mate with a 6700 and a pixel loop a few km away but no GPSDO as yet. We both have access to seaside properties 45 km away.
Lots of fun ahead.
Andrew
(Edited)
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Charles - K5UA

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Pyschoacoustic sound stage......... About 4 years ago I worked about 6 hours of CW in a Field Day contest using a friend's K3 . Did not know about the psychoacoustic capability of the K3 that was engaged when I sat down for my turn at the radio. The CW note was odd sounding in the headphones, almost raspy. Didn't think too much about it in the heat of the contest. Took a one hour catnap after 6 hours and when I rolled out of the bed I hit the floor with a bad case of vertigo and tinnitus. The vertigo lasted about 6 months, and i still have the tinnitus.

Coincidence. Maybe. Just know I'll never want to be exposed to a psychacoustic soundstage again. Just wanted to mention this in case anyone else runs into this problem. Not sure anyone knows what activates vertigo and tinnitus, so would not rule out psychoacoustic input to the auditory system as a catalyst to the very irritating condition.

Would be interested to hear if anyone else has experienced this effect after hours of exposure to psychacoustic auditory input.
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George O'Brien, AB4FH

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Charles, I'm sorry to hear of your bad experience. Subsonics can have severe effects and I don't know what constant phase shifting might do to certain people. Most of us who use diversity reception characterize the sound as "hollow" an almost ethereal quality. With a good setup one can feel immersed in the sound. Noise is much less intrusive and listening fatigue is significantly reduced.
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James Kirk

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Call Hupy and Abraham
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DrTeeth

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Maybe increase the spatial awareness with some Lysergic acid diethylamide, maybe a touch of SSRI for bravado?
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Stu Phillips - K6TU, Elmer

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Or maybe some mushrooms? ;-)
Stu K6TU

PS: Seriously, this works!
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DrTeeth

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I believe you, it sounds amazing (no pun intended).
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Steve W6SDM

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Having actually experienced the 1960s, I can only say that if use use Stu's device then say your call sign backwards, you'll see images of Hiram Percy Maxim in your English muffin the next morning.
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Watts - K4QJZ

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Stu, great write up, what an excellent way to help folk’s without Diversity reception knowledge understand the advantage and practical application. It will be interesting to see what comes next from Diversity reception mode.
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philip.theis, Elmer

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Very nice, I love diversity
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Sergey, R5AU

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I wanna to say - diversity what we need definetely ,
as ex. for visualize:
https://www.youtube.com/watch?v=sFpSQQ_dBE4
or
https://www.youtube.com/watch?v=SD0V2D5S1dU
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Barry N1EU

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I've been posting diversity recordings on the Web for the past 10 years.  Just holding out hope that Flex can bring a 6K diversity platform to market at a lower price point than the 6700.  Until then, my diversity rig is the Orion2/RX366.
(Edited)
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KM4CQG

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When considering the purchase of my 6500 I looked into
local noise levels.

Stu are you saying regardless of noise this still works?
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Stu Phillips - K6TU, Elmer

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Yes.

I happened to use an antenna for the second slice that has a fair amount of rejection of local noise sources but the real secret in the cookie dough is the physical separation between the antennas.

That's independent of noise.

The ionosphere is a fluid and very dynamic - think on a very small time scale due to heating effects, ionization rates, changes in the magnetic field of the Earth and coupling of high altitude weather up into the higher levels of the atmosphere (at a minimum).

As a result, the reflection/refraction of the received signal at ONE point of observation is continually changing - this is the QSB you hear which will generally be more obvious on weaker signals.  This is because there are multiple signal paths between the transmitter and receiver as a radiated signal has many "launch" angles from the antenna.  So there are really multiple "rays" propagating through a shifting medium that provides the reflection/refraction.

Ray combining can occur constructively where the combinations are all in phase - this makes the received signal stronger.

Or, they can combine destructively where the combinations are in opposite phase - this makes the received signal weaker.

CRITICAL - and why I emphasized the ONE above...

If you have a SECOND point of observation that is physically separated from the first, you will see different combination effects because the effective phase of the different arriving signals gets shifted.  Different phase means different combining effects.

When I chose the site for my PixelLoop I wanted to get it as far away from my 160m vertical for two reasons...  even with the protection relay in the PixelLoop, I wanted to provide some isolation from the effect of dumping 1500 watts into the near field... Second, I wanted to get the second antenna away from the inevitable local noise that gets re-radiated from the vertical.

Serendipitously this put the antenna about 600 feet from my tower...  about as far as it can be without going off my property!

On 10m this is about 20 wavelengths dropping to about 3 on 160m...  rough math.

The multiple wave lengths between the two antennas guarantees that the combining effects of the different arriving "rays" is different.  Statistically it must be possible that they could be the same where both fade at the same time but given the dynamics of the ionosphere, I believe the probability is very low.

Sorry for the long explanation...

The net is that the arriving signals at the two antennas are different in terms of fading and other effects reducing our ability to copy the signal.  By running both signals together from the separate SCUs (which are phase synchronous - thus preserving the phase differences between the two incoming signals) into the headphones on different channels, our brain processes this onto a mental "sound stage".

The auditory processor in our brain is amazingly good - evolution at work here... as we process the sounds arriving in each ear and can instantly perceive where the sound is coming from.  The brain is also really good at selective processing - being able to focus what you want to hear.

That's how it all works!

The key is antenna siting - you need the physical separation in order to benefit from the diversity reception.

I have 600 feet or so of separation plus the coax run from the PixelLoop is about 500 feet - adding a significant amount of delay line effect.  That must also play together.

Finally (everyone heaves a sigh of relief)... you can also use diversity to reduce or even eliminate the impact of noise on a received signal - this is how the active noise reducers work that are sold by MFJ et al.  By changing the phase and matching the amplitude of the noise from one antenna and mixing it with the signal at the second, you can cancel out the local noise signal.  Thing Noise Reduction headsets - they work in the same way.

That's the real differentiation of the 6700 over the 6500 - and as Gerald wrote in the recent Flex Insider, that's going to be a big feature focus area in 1.5.  Many of the effects can be done with a single SCU BTW so all the models will benefit.

Stu K6TU
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Ken - NM9P, Elmer

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Stu, I had never thought about the phase induced stereo imaging effects translating into spatial placement of signals in an RF diversity system.  That is a very interesting concept.  

I wonder what would happen if you had two pixel receiving loops, spaced 600 or more feet apart, each with directional controls, or perhaps just at 90 degree angles to one another.  Being evenly matched and low noise antennas, would this magnify the "psycho-acoustical stereo placement effect?"  

It would be interesting to experiment....

Ken - NM9P
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Richard McClelland, AA5S

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I wonder whether the Array Solutions Shared Apex Loop Array might achieve similar effects without having such large physical separation?   From the Array Solutions website:

"The antenna is a true-time-delay array with four identical wire loops supported by a single non-conductive mast. Signals from each loop are transferred through a ferrite coupler to a short balanced line that connects to the switch/ combiner/amp enclosure mounted at the base of the antenna."

Might be worth a try when the option of large physical separation isn't available.

Rick, AA5S
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Stu Phillips - K6TU, Elmer

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Rick,

I looked at and modeled this antenna fairly extensively before buying the Pixel Loop - it's a fine design and if you have the space for the larger version will perform as well as the Pixel Loop and with better directivity on 160m.  The smaller version will work also on the higher bands.

The time delay mentioned is the way in which directivity is created from the antenna. In this case, its the time delay between the same signal arriving at element pairs.  The time delay and phasing delay difference cancels out signals arriving off the back and provides the F/B ratio of the antenna.

As a side note, one of my friends was on the C82DX operation - they had a Pixel Loop and a Shared Apex Loop - both delivered similar results.

To get the diversity benefit I describe you need physical separation.  From a little digging via Google, it looks like 0.5 to 0.8 wavelengths separation are probably the minimum...

An alternative is Polarization Diversity - ie use a Yagi and a Vertical.  Similar path differences will exist in polarization as with physical separation.

This is well documented in the literature and I will (at some point) dig out my ancient R5 vertical and see how that performs with polarization diversity.

Stu K6TU
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Stu Phillips - K6TU, Elmer

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Ken,

Re the two separated PixelLoops...  i don't know if it would magnify the effect of the psycho acoustics.  I started thinking about two PixelLoops at 90 degrees to one another to phase together and improve the directivity F/B...

Stu K6TU 
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Richard McClelland, AA5S

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I was sort of missing the point, wasn't I?   I just checked my property and the max distance I can achieve is 175' separation unless I encroach on a drainage easement abutting the back of my property.  I could achieve 660' separation if I did that but my neighbors might ask about my activities.  One of them has already mentioned that he watched me for several hours as I was putting up my delta loop and he was afraid that I was in some type of peril.  I told him that I was putting up a ham antenna and he hasn't spoken to me since.  I hope I didn't offend him.
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Stu Phillips - K6TU, Elmer

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Give polarization diversity a try first...  175' is still almost 6 wavelengths on 10m...

Stu K6TU

PS: in my Homer moment of the day - doh!  600 feet separation is just over 1 wavelength on 160m...  imperial/metric, metric/imperial... doh!
(Edited)
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Richard McClelland, AA5S

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Getting a 6700 in the shack is the greater challenge but your suggestion seems quite sound.
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James Kirk

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The 5000 with a second receiver works well and is a bargain now on the used market.
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Sergey, R5AU

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Well, BTW, what we are need in 6700- need to be implemented possibility to choose of the DAX  channel separately for each paired slice. I guess it will be improved in the upcoming versions, ex.: to test with http://www.sm5bsz.com/linuxdsp/linrad.htm
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KY6LA - Howard, Elmer

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I agree with Stu... in a previous incarnation I used polarization diversity which definitely worked

Being real estate challenged with only 1/2 Acre and a large SteppIR MonstIR dominating the lot, I cannot achieve meaningful horizontal separation

So Stu has inspired me to get a vertical installed so that i can get Polarization Diversity.
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Ken - NM9P, Elmer

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When I ran W1AW/9 (Indiana) a few months ago on 40 SSB I ran primitive polarization diversity...called an antenna switch!  

But I was amazed even then how changing from my 160 OCF Dipole to the Full sized Elevated Vertical Ground Plane would bring a station out of the noise or the pileup!  
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KM4CQG

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Stu

Thanks for the great briefing I spoke with Bob Heil a while back he has a phase shifting in his headphones and it does work.

Based on what your describing I could indeed make a 6500 perform the same way without a 2nd SCU needed.

On Fri when I Fly back to Florida I am going t o look for a 2nd Antenna Site on my property for trying this out.

Thanks Again
Ian
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Stu Phillips - K6TU, Elmer

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Ian,

I don't believe that you can do this with a 6500 - with only one SCU you have a tie between a single receive antenna port and all the slices serviced by that SCU.

The second SCU allows a second slice to be sourced from a different receive antenna.

The headphone mechanism you describe is like binarual audio - one channel is phased shifted 90 degrees before being fed into one ear piece.  Its the same as steaming I data to one ear and Q to the other as PowerSDR did when you turned binaural on.  The effect is similar audibly because its the audio phase difference in the signals from the two antenna/receivers that enables the brain to create the sound stage.

You can certainly manually switch between the two antenna but you aren't going to get the same diversity real time reception provided by the 6700 - the signals bounce around way too quickly for manual switching to work.

Diversity on the 6000 requires the two SCUs - only present in the 6700.

Stu K6TU
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dl9eri/oe9eri

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You can do this with an DXE NCC-1 connected to the 6500 or 6300 and the DXE-RTR-1A as Antenna-Switch - so it does not need two SCUs..... It works here with my 6500 and I use it for noise-blanking of house-made QRM or 360 degree phasing of two different antennas.
(Edited)
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KM4CQG

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Stu

Can a 2nd or 3rd receiver not be from a different antenna source?

This is what he is speaking of.



Ian
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George O'Brien, AB4FH

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We shouldn't confuse beam steering and noise cancellation that these devices provide with stereo diversity reception that Stu experienced. 
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Stu Phillips - K6TU, Elmer

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Don't confuse noise cancellation which is the function of the DXE NCC-1 and diversity reception.  They are two different things.

Noise cancellation uses a second sense antenna plus an external unit to generate an anti-phase noise source that mixed with the primary antenna, cancels some of the noise signal.  Errors in phase and magnitude introduced by the external unit (usually done in the analog domain) result in less than perfect noise reduction.  That said, these units work and work fairly well.

A 6700 could support software that did this perfectly in the digital domain using two SCUs - not possible with a single SCU at least in terms of conventional anti-phase noise reduction.  There are some possibilities for the 6500 and 6300 that don't depend on having a second SCU - but this is, as Gerald correctly described it, is a science experiment.

Diversity reception is a while different critter - I'll look and see if I can find some better descriptions that the one I've provided here.

Bottom line; DIVERSITY reception currently requires two SCUs - that means 6700 and 6700R only.

Stu K6TU
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George O'Brien, AB4FH

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There is an excellent writeup by W8JI on the whole topic at   w8ji.com/polarization_and_diversity_htm

I recommend jumping down to the section entitled "Diversity Receivers and Reception".  A significant quote is "To be effective, signals cannot just be directly mixed either at audio, IF or radio frequencies."  He achieved the stereo diversity by phase locking two separate receivers, heavily modified Drake R4C's, even to the point that the crystal filters were hand selected for equal group delay over the filter passband.  At the time of article, Tom Rauch wrote "I currently use an Elecraft K# since it is the only system that phase-locks two identical receivers..."  Today, with the Flex 6700 and perhaps also with the Flex 5000 (I don't know that the two receivers are phase locked) we have similar capabilities.  Are the results worth the effort?  He says "The difference can be worth as much as a signall being nearly readability 5 in stereo to readabillity 2 without."

This psychoacoustic soundstage cannot be achieved through phase shifting of the same antenna and adding to the opposite ear.  Two separate antennas with either different polarizations H and V or if with the same  polarization separated by 2 lambda or more provide the RF signals required.

Finally, Tom has two sound files that help you hear what to listen for when testing for diversity capability.



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Tom Warren

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Is this technology akin to that used with the large interferometers, arrays of dishes?

Tom
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Bill Sharp

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Huh? I don't even understand what you said. "Cognitive Processor Bus" ????  I don't know what it is ......but I think that I want one. No, now I'm sure of it.... I must have one. Or maybe two?! Ham radio is just getting way to sophisticated for me I guess. :))
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George O'Brien, AB4FH

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In radio astronomy signals from widely separated antennas are summed while maintaining their phase coherence through nanosecond synchronization via accurate and stable atomic clocks.  This allows them to act like an extremely wide aperture antenna.  What the researchers are trying to achieve with this extremely wide aperture is to increase the angular resolution or resolving power.  These antennas are sometimes on different continents.

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George O'Brien, AB4FH

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Here's a real world example of diversity receive at work.  I've captured the signal of a station in Hawaii, NH7O, that I just completed an 80 meter QSO with.  He was in the noise and barely leaves a trace in the waterfall but with DIV turned on we were able to have a readable exchange.  The signal is so hard to see that I placed a yellow circle around it. BTW my QTH is northeast SC, grid EM84RQ. I was using a Pixeloop on slice A antenna RXA.  Slice B (on second SCU) used an inverted L (50 ftvertical section + 95 ft horizontal section sloping upward to 65 ft) antenna ANT1.  Slice C used ANT1 on transmit.  1000 watts output power RST exchanged 449.

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James Kirk

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Ken - NM9P, Elmer

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Impressive!