[CQ-Contest] Flex Radio Question

Stuart Phillips stu at ridgelift.com
Tue May 6 11:40:42 EDT 2014


I’m getting bounces on your tod at k0to.us address so hope you see this via
the reflector…

Kevin K6TD (former Cal QSO Party chairman, former NCCC director and
Dxpedition member of K4M and C82DX) sold his K3 a couple of months after
purchasing his 6700 - he’s an active contester.

The K3 is a fine radio and to me, this discussion isn’t about the Flex
6000 being its replacement - that’s a matter of personal preference.

The Flex 6500 is comparably priced to a decently configured K3 for
equivalent features.  By the time you add roofing filters, P3 and
associated VGA display adaptor, you are in the same price range.  Yes, the
6700 is a higher priced but it also has many features the K3 does not - so
not an equivalent comparison.

I am a very active contester - I don’t have a super station but I am
competitive against similarly equipped stations here on the West Coast.  I
run legal limit to a DB18E at 50’ with other antennas for the low bands.
In contests I use Writelog and everything in the station is computer
controlled - amps, SteppIR etc.  I contest all three modes - phone, CW and
RTTY with phone and RTTY being my stronger events.

I don’t see any latency related issues when operating the radio.  The
radio command is perceptually “instant” - you make a change and there is
no perceivable lag - this is true of tuning as well as interfacing with
the radio controls.  In contests I regularly run over 100 Qs an hour with
sustained bursts of 240 or better - the radio isn’t the rate limiter - now
its the operator!

The Flex 6000 series radios have a high power real time computer system IN
THE RADIO - a high speed processor, separate DSP, maintenance processors
and FPGA.  The FPGA in particular does the high speed heavy lifting of the
> 240 M samples/second from the Analog/Digital converter.  The client
>running on a PC is now a thin client providing display and UI to the
>remote controlled radio.

BTW, the separate receivers are NOT time sliced - they are all driven from
the same sample set - you are effectively capturing 120 Mhz of spectrum
all the time - that’s how you get the separate receivers.

However, computer control of ANY radio or station element introduces a new
set of considerations for contest operation - how to integrate these
elements into the WORKFLOW associated with the logging program.  In other
words, never having to change window focus away from the logging program
in order to maximize rate and minimize operator work load.

Even adding a computer controlled rotor to a conventional station
introduces the same problem - moving window focus is a no no in my view.

Those operating K3’s remotely have the option of the K3/0 - an RF empty K3
with front panel and all the knobs - serving a a second computer to
control the remote radio.  In my case, I command the remote radio via a
combination of the FlexControl (a tuning knob and switch peripheral that
enables radio control without changing window focus) and an iPad app I
developed (K6TU Control) which serves as a virtual front panel for the
radio (and MUCH less expensive than a K3/0 :-).

Contester adoption of SDR radios may well be similar to the AM/SSB
argument - both require a change and hams don’t like change.

Attention to work flow integration is critical when computer controlling
the radio or the station - there are now off the shelf solutions that
enable this in SO1R (I’m still easing my way into SO2R) with the FlexRadio
6000 series radios.

With the workflow addressed, the performance and ease of operation of the
radio is spectacular.

- Brick wall filters
- Ultra clean audio making stations easy to copy and with low operator
- HD pan adaptors
- Multiple receivers

Restating the issue - its about workflow integration of a computer
controlled station.  This is the root issue and perception issue that has
limited the adoption of SDRs to date - the issues are solved and I’m
delighted to have SDR capabilities in my ham radio operation!

Stu K6TU

On 5/5/14, 9:16 PM, "Tod Olson" <tod at k0to.us> wrote:

>You may be correct ― I think the thing that I felt was coming through in
>the email I received was the mechanics of logging entries and controlling
>the radio. I am curious to know the call of the person in the Bay area to
>whom you are referring - the one who chose to replace their K3.
>You certainly are correct that successful use of any type of radio in a
>contest requires thoughtful consideration of workflow to maximize your
>personal effectiveness.
>I have only briefly used a K3 at Ken Kopp's, [K0PP] in Anaconda, MT. It is
>a nice radio with good ‘properties’ but I would expect it might take a
>couple years for me to get everything working together well <radio,
>switching, antennas and operator>. I would certainly expect the same if I
>were to start using a Flex Radio.
>Perhaps there is a difference in ‘ease of use’ that depends on logging
>programs or maybe I just don’t understand all the details. I can imagine
>that if one is running stations there might be one operating
>characteristic and if one were doing ‘search and pounce’ there would be
>another. I don’t have a feel for how quickly one can change frequencies or
>swap radios or swap frequencies in SO2R etc. Somehow, correctly or
>incorrectly, I would expect slight delays [command latency] between things
>that I might not expect from the non-SDR equipment. Also, Stu, there were
>only a few responses and only a couple from people I generally associate
>with long term, skillful contest operation. Please note that I am not
>focussed on the people who ‘win’ contests; there are a lot of very good
>contest operators who will never win a contest from their current
>It may be that the cost of the Flex Radio relative to a K3 is limiting the
>number of persons who have elected to use them to contest ― that might
>also reduce the number of responses to my question.
>Several years ago I looked at SDR’s for contesting and felt at that time
>command latency would be unacceptable. With Moore’s law working I would
>suppose that the hardware is at least 8 times more powerful and perhaps
>command latency is no longer an issue. Certainly the A/D conversions are
>faster and a lot of software has been written to take advantage of that.
>The idea that a single Flex Radio can operate as several independent
>radios on different frequencies and modes simultaneously [ OK, time
>multiplexed ] is interesting too. But why do you suppose that we don’t
>hear more about SDR’s being used as contest radios? Are we at some sort of
>‘Spark vs. CW‘ or ‘SSB vs.AM’ technology change? I wasn’t around for the
>Spark change but I remember well the SSB/AM transition and as an early
>adopter [1955] remember folks on 75 phone making us SSB guys operate from
>3990-4000 kHz if we wanted them to leave us alone. It only took about five
>years and folks recognized that SSB was a much better choice than AM. The
>same does not seem to be the case for the SDR’s. What do you suppose are
>the considerations that seem to be slowing the adoption of the technology?
>Tod, K0TO
>On 5/5/14, 8:33 PM, "Stuart Phillips" <stu at ridgelift.com> wrote:
>>Really?  Who fed you this line?
>>This is just utterly wrong - computer control of any radio requires some
>>consideration for workflow.  Note - ANY radio.
>>I successfully contest all modes with FlexRadio products and I¹m
>>with my 6700.  At least one other serious contester here in the Bay Area
>>sold his K3 after buying a 6700.
>>You never responded to my email offering comments - standing offer to you
>>or anyone else - I am a serious contester with a FlexRadio 6700 and very
>>happy - even happier to answer questions!
>>Sorry Tod but you didn¹t get the straight scoop.
>>Stu K6TU

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