Wednesday, July 19, 2017

The world of SO2V - some thoughts by a newbie operator.


 In the last 20 years or so I have taken quite a fancy to radio amateur competitions; known in Europe as radio sport. While I have won numerous section awards and even a few 1st place plaques, with the kinds of operations (mostly portable) that
I run, there has been a limit to my success.  To resolve this, in the last year I have been learning and perfecting the art of SO2-V (Single-OP 2 VFO's). 

I recently wrote a BLOG entry entitled:
LEARNING the ART of LEVERAGING DUAL RECEIVE 
[CLICK HERE] to read this article.
 
You may have heard about SO2-R (Single-OP 2 Radios).  Altho similar in concept SO2-R requires two radios and 2 amplifiers, along with a number of control units to allocate the antennas and other units between the two radios. In addition to being quite expensive, there is a significant increase in the number of things that can go wrong at any moment.

With SO2-V only one radio and one amplifier is needed. This reduces the cost
and the complexity
of the station setup significantly. It is also considerably easier to learn the art of SO2-V in contrast to the more complicated SO2-R method.


In 2014 I joined up with  George N6GEO to run the RTTY RU contest from Radio Reef (KP2M) on St. Croix using
the WP2/WQ6X callsign. 
 
For that contest we brought our own equipment to run:  a FLEX-1500 SDR radio and a Tokyo HY-Power 45b amp running the onsite Alpha 87 amplifier at a
cool 149 watts, qualifying as
a low power (LP) station. 
 
Before and after that contest I made use of the onsite Yaesu FT-1000mp transceiver to work CW & SSB contacts, instead of the Elecraft K3 which
(thanks to guest OP'ing @NX6T) I have become bored with operating. 
The FT-1000mp has more knobs to twiddle and is more fun to operate.

I was so taken with the Yaesu transceiver that a couple of years ago, I brought a fully-filtered FT-1000mp radio into my operating world, replacing the cherished Yaesu FT-920. Amongst all its advanced features (such as an incredible eDSP facility), the 1000mp is equipped with in-band dual receive capabilities. 

Most radios sport dual VFOs, but it is another world altogether having access to dual-receive capability.  With the 1000mp, SO2V (Single OP 2 VFOs) became
an operating possibility for WQ6X.

SO2-V in N1MM+ Logging Software
The major "rice box" manufacturers all offer radios sporting dual receive. 
With Kenwood, while the TS-950SDX is no longer made, the TS-2000 is still
being offered.  With ICOM, the retired 756 PRO III, along with the current 7600 & 7800 series provide dual receive. Yaesu weighs in with the FT-1000mp and the
MK-V, as well as the FT-2000 and FTDX-5000 radios. 

In the USA, Ten Tec offers the Orion II and of course the Elecraft K3 can be upgraded for dual-receive. Each manufacturer's approach to dual-receive
have their pluses and minuses.
 
Before I switched over to the FT-1000mp, I had the incredible FT-920 at the operating helm. Unfortunately, from the true dual-receive perspective, the
920's "DualWatch" is incapable of operating in a true SO2V fashion. 
The 920 DualWatch utilizes a "polling" mechanism between VFOs A & B.
As such, VFO-A & VFO-B cannot receive simultaneously.
It's either one or the other.



In contrast, the FT-1000mp utilizes two separate receive line circuits which can be
active simultaneously. 
(Of course during transmit BOTH receivers are silenced.). 

I configured WQ6X's 1000mp to split the audio between left/right ears, with independent volume control in each ear. 
 
 
Unfortunately, the eDSP operates ONLY with VFO-A's receiver.  My solution to this shortcoming was simply to route the VFO-B's receive audio to an outboard MFJ 752-C Signal shaper and/or JPS NIR-12 DSP unit (depending on my "mood"); units which have been languishing on the shelf after acquiring the FT-1000mp.
 
MFJ 752-C
While both of these units are well over 20 years old, sometimes it is the older technology which makes the difference.  In the early 1980's, many of the more expensive radios had Audio Peak Filters (APF) built-in. 


For the lower-end radios, the MFJ and JPS filters essentially accomplished
the same thing.

JPS NIR-12

Even the inexpensive Radio Shack outboard audio DSP filter made quite a difference
in most radios.


Because the FT-1000mp has no SUB-Rx shift/width/notch filters, the MFJ/JPS filters more-or-less accomplish the same thing.

One day I would like to test an old Radio Shack DSP filter on the FT-1000mp SUB-Rx.  This year during Field Day I test-drove running the FT-1000mp's
sub receiver audio thru the classic Autek QF-1A audio filter. 
I was surprisingly disappointed.

While the QF-1A is correctly a MONO device, not being able
to bypass it mid-contest (by flicking a switch) limited its possibilities.  
 
However the QF-1A is still the filter of choice when I run CW contests remotely from NX6T
in Fallbrook.
 
 
In the ideal world, dual receive allows me several possibilities:
  1. In a single mode contest, I can run a frequency (VFO-A) while
    tuning the band (VFO-B) looking for multipliers.
  2. In multi-mode contests such as state QSO parties or the 10 meter contest and Field Day, one VFO can tune the CW portion of the band while the
    other tunes the SSB segments. Either mode can be a RUN frequency
    while S&P'ing using the other mode.
  3. DX stations running "split" can use VFO-B to tune for stations while using and monitoring the RUN frequency. As mentioned earlier, in 2014, I spent
    10 days as WP2/WQ6X at Radio Reef on the island of St. Croix.
    Outside of the contest period WP2/WQ6X put over 2,000 QSOs into the log. In retrospect, running the CW and SSB pileups should have been done split, using VFO-B. Unfortunately the newness of dual-receive (and the nightly enjoyment of some island grog) kept the use of dual receive out of my reach.
  4. Dual receive also allows a technique known as "diversity reception",
    a methodology described briefly in the FT-1000mp operator's manual.
    Search the internet for "diversity reception" to discover what interesting things this approach can provide.  To help you with this I ran a web-search and came up with a lot of interesting items.
    [
    CLICK HERE] to see that search.

To accomplish SO2-V using the
FT-1000mp, I configured the radio to direct most of VOF-A's audio to the left ear and most of VFO-B's audio to the right ear. 
 
The Yaesu FT-1000mp is equipped with firmware menu settings allowing custom-configuration of the split audio.
 
The menu settings I use for the FT-1000mp allow both AF gain controls to act like gain controls. 
 
In contrast, with the old ICOM 756-PRO (about the same age as the 1000mp), those controls are labeled: AF Gain & BALANCE.


If you've never run split audio before, it might seem a little daunting at first. 
Before jumping into actual SO2-V contesting using dual receive, I spent a couple of weeks practicing using both VFO's together until I felt comfortable with the method.  Like SO2-R, SO2-V is largely an ART, employing radio technology.
 
Being one of the first transceivers to offer up dual-receive, the FT-1000mp was
well designed to locate the most used controls (for VFO-A) in the center of the radio and to the left of center. This correlates with the left ear.
 

The VFO-B knob is more to the right, correlating with the right ear. 
 
When running a frequency with VFO-A,
I LOCK that VFO on the run frequency so I don't inadvertently shift frequency when
I really mean to turn the VFO-B as I S&P elsewhere on the band.

In the contest world, properly taking advantage of dual-receive requires
CAT (Computer-Aided Transceive) software designed for this purpose. 
While WinTest and WriteLog can probably do the job, since N1MM has become N1MM+, I have found their approach to be the most effective
match to my way of operating.
 

 
To be most effective, I recommend the use of dual computer monitors. 
 
When I run portable @W7AYT the WIN-7 Toshiba laptop I use for contest operating has an HDMI port making this an easy configuration. 
 
 
 
Somehow, the Toshiba laptop even "remembers" the different monitors
I plug into it. Configuring the external monitor as the MAIN screen, leaves
the laptop to display things that do not need my immediate attention.

Then again, as you can see from the above photo, for the 2016 SSB Sweepstakes portable setup @ W7AYT I managed to fit everything (N1MM+ related) on the LARGE video monitor. Both methods have their advantages. 
 
To get used to the frantic nature of SO2-V using the contest pile-up trainer can help you work through the confusion before the actual contest weekend arrives.

  
Sometime ago, someone sent me a document with a detailed write up on running SO2V using N1MM. It is from this document that I learned the fundamentals of SO2-V contesting. From there, it was just practice, practice, practice. I searched the internet for this document and could not find it. Therefore, to make things easier, I uploaded a copy of it onto the WQ6X.Info web server. [CLICK HERE]
to read this document.

In summary, while a more complex method for running radiosport contests,
SO2-V can certainly increase your operating efficiency if you take the time to
learn the ins-and-outs of this method. I don't wish you luck with SO2-V.
Instead, I wish you SUCCESS.

Listen carefully for me during my next portable contest operation from
W7AYT - I may well be running SO2-V.



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