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OT: Dayton New Equipment Show

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Edward R Cole

OT: Dayton New Equipment Show

Certainly Dayton is one of the premier ham events for rolling out new
equipment to show.

I wonder if any have passed by a huge crowd around Flex? Their
website now shows the Flex-6000/6700 newest entry into the SDR
market. Very high end at $6999.

Only mentioning it as interesting to see what other outfits are
coming out with. My K3 was my LAST big ham radio purchase ...have to
last me a lifetime! The KX3 is not what I consider "big", but will be "nice"!

Side comment Eric is savy to help the gals by getting the web order
installed for the KAT500.

73, Ed - KL7UW, WD2XSH/45
======================================
BP40IQ 500 KHz - 10-GHz www.kl7uw.com
EME: 50-1.1kw?, 144-1.4kw, 432-QRT, 1296-?, 3400-?
DUBUS Magazine USA Rep [hidden email]
"Kits made by KL7UW" http://www.kl7uw.com/kits.htm
======================================
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Tony Estep

Re: OT: Dayton New Equipment Show

On Sat, May 19, 2012 at 11:53 AM, Edward R. Cole <[hidden email]>wrote:

> ...website now shows the Flex-6000/6700 newest entry into the SDR
> market....

===========
Said to be digital from antenna connector to output. Their hardware has
long needed updating, so perhaps this will be it. However, Flex's really
weak link has always been their software/systems integration, so it remains
to be seen if this does anything to mitigate that.

Tony KT0NY

--
http://www.isb.edu/faculty/facultydir.aspx?ddlFaculty=352
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Joe Subich, W4TV-4

Re: OT: Dayton New Equipment Show

The Flex 6000/6700 is an "on frequency" direct digital conversion
radio - that is a 16 bit analog to digital converter operating at
the "front end" of the radio with no intermediate conversion/IF
and filtering stages. In addition, all of the DSP is contained
in the radio (no more PowerSRD). The new software for the Flex
6000/6700 (reportedly "PowerRX") is essentially a "glass control
panel").

A general purpose computer is required for PowerRX but communication
between the computer and transceiver is via TCP/IP which means the
computer can be anywhere. Audio input and output will be available
both on the transceiver and from PowerRX (interesting for remote
operation scenarios).

The issue will be the severely limited dynamic range of the 16 bit
ADC. Without effective AGC ahead of the ADC there *will* be overload
problems on crowded bands (e.g. 160/80/40) where any transceiver must
deal with many extremely strong ("local") signals while maintaining
maximum sensitivity. With AGC, the strong local signals will cause
"blocking" as the gain is reduced to prevent overflow of the ADC.

The new Flex design is certainly "interesting" but may not truly be
ready for critical "real world" use with the widely varying signal
levels in amateur service.

73,

... Joe, W4TV

On 5/19/2012 3:43 PM, Tony Estep wrote:

> On Sat, May 19, 2012 at 11:53 AM, Edward R. Cole<[hidden email]>wrote:
>
>> ...website now shows the Flex-6000/6700 newest entry into the SDR
>> market....
>
> ===========
> Said to be digital from antenna connector to output. Their hardware has
> long needed updating, so perhaps this will be it. However, Flex's really
> weak link has always been their software/systems integration, so it remains
> to be seen if this does anything to mitigate that.
>
> Tony KT0NY
>
>
>

Tom Azlin N4ZPT-2

Re: OT: Dayton New Equipment Show

decimation counts

On 5/19/2012 7:29 PM, Joe Subich, W4TV wrote:
> The issue will be the severely limited dynamic range of the 16 bit
> ADC. Without effective AGC ahead of the ADC there *will* be overload
> problems on crowded bands (e.g. 160/80/40) where any transceiver must
> deal with many extremely strong ("local") signals while maintaining
> maximum sensitivity. With AGC, the strong local signals will cause
> "blocking" as the gain is reduced to prevent overflow of the ADC.

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wb4jfi

Re: OT: Dayton New Equipment Show

In reply to this post by Joe Subich, W4TV-4

Joe, I'm not sure some of your suppositions are correct.

First of all, the ADC samples at a significantly higher rate than the
incoming RF (for HF), at 245.76MHz. Then, those samples go through
decimation inside Digital DownConverter (DDC) in the FPGA, and the higher
the decimation, the more the processing gain, and therefore added "bits". I
believe the typical assumption is that you gain the equivalent of approx.
one-half bit (3dB) of dynamic range every time you decimate (divide) the
sample rate by two. This is real gain, not some imaginary trick or magic.
If you start with a 245.76MHz sample rate, and end up with 240kHz (example),
you could achieve a processing gain of an additional five bits, or 30dB. If
my quick math is correct. All without AGC or other games.

Throw away at least one A/D bit, so 15 bits(ADC) plus five bits(proc gain)
yields 20 bits, or about 120dB of dynamic range. I must be a little off, as
I saw one note on the Flex reflector that they think 153dB or so of dynamic
range. Maybe by lowering the final sample rate some more, or not tossing
all of one bit of the ADC. I believe Mitola suggested that 130dB of dynamic
range is adequate for HF, I'm not sure if that includes noise from storms,
etc. BTW, the new software is called SmartSDR.

I have been playing with DDC receivers for a couple of years now, and I
firmly believe they will be the future. I suggest that thorough research of
DDC-based receiver design will alter your perception. It did mine.

I love my K3/P3, and do not plan to replace it anytime soon. It just works
GREAT, and is a nice compact box without requiring a computer to use. But,
I was very tempted to by a Flex 6500. That is, until I saw the $200 per
year charge for the software. Technically, very leading edge. Marketing,
you decide.

Hope this isn't too off-topic.
73,
Terry, WB4JFI

-----Original Message-----
From: Joe Subich, W4TV
Sent: Saturday, May 19, 2012 7:29 PM
To: [hidden email]
Subject: Re: [Elecraft] OT: Dayton New Equipment Show

The Flex 6000/6700 is an "on frequency" direct digital conversion
radio - that is a 16 bit analog to digital converter operating at
the "front end" of the radio with no intermediate conversion/IF
and filtering stages. In addition, all of the DSP is contained
in the radio (no more PowerSRD). The new software for the Flex
6000/6700 (reportedly "PowerRX") is essentially a "glass control
panel").

A general purpose computer is required for PowerRX but communication
between the computer and transceiver is via TCP/IP which means the
computer can be anywhere. Audio input and output will be available
both on the transceiver and from PowerRX (interesting for remote
operation scenarios).

The issue will be the severely limited dynamic range of the 16 bit
ADC. Without effective AGC ahead of the ADC there *will* be overload
problems on crowded bands (e.g. 160/80/40) where any transceiver must
deal with many extremely strong ("local") signals while maintaining
maximum sensitivity. With AGC, the strong local signals will cause
"blocking" as the gain is reduced to prevent overflow of the ADC.

The new Flex design is certainly "interesting" but may not truly be
ready for critical "real world" use with the widely varying signal
levels in amateur service.

73,

... Joe, W4TV

On 5/19/2012 3:43 PM, Tony Estep wrote:

> On Sat, May 19, 2012 at 11:53 AM, Edward R.
> Cole<[hidden email]>wrote:
>
>> ...website now shows the Flex-6000/6700 newest entry into the SDR
>> market....
>
> ===========
> Said to be digital from antenna connector to output. Their hardware has
> long needed updating, so perhaps this will be it. However, Flex's really
> weak link has always been their software/systems integration, so it
> remains
> to be seen if this does anything to mitigate that.
>
> Tony KT0NY
>
>
>

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Joe Subich, W4TV-4

Re: OT: Dayton New Equipment Show

In reply to this post by Tom Azlin N4ZPT-2

Decimation can help but it is not a magic bullet that eliminates
the effects of ADC overflow and/or blocking due to gain reduction.

73,

... Joe, W4TV

On 5/19/2012 7:57 PM, Tom Azlin N4ZPT wrote:

> decimation counts
>
> On 5/19/2012 7:29 PM, Joe Subich, W4TV wrote:
>> The issue will be the severely limited dynamic range of the 16 bit
>> ADC. Without effective AGC ahead of the ADC there *will* be overload
>> problems on crowded bands (e.g. 160/80/40) where any transceiver must
>> deal with many extremely strong ("local") signals while maintaining
>> maximum sensitivity. With AGC, the strong local signals will cause
>> "blocking" as the gain is reduced to prevent overflow of the ADC.
>
> ______________________________________________________________
> 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
>

Tom Azlin N4ZPT-2

Re: OT: Dayton New Equipment Show

Hi Joe,

Guess we will have to await independent testing. The Flex folks seem to
assert they have the equivalent of more than 24 bit when dealing with
adjacent strong signals.

From the Flex reflector...

> Just in rough numbers, you get a 1/2-bit for every divide-by-two decimation
> you do. If you are looking at dynamic range in a 500Hz bandwidth (this is
> what we typically do). The math I generally use to get there is
> log(f1/f2)/log(2)/2. I just think this way as a programmer (do everything
> in base 2). So if you take log(245.76E6/500)/log(2)/2 you get 9.4 extra
> bits when added to the 16 gives you 25.5 bits (152.7dB dynamic range).
> This assumes all 16-bits of the ADC are "good" which is probably not a
> good assumption. I'd have to pull out the notes and look at the data sheet
> again, but this should give you a rough idea. Hopefully I haven't made an
> additional "duh" today myself!
>
> Bottom line -- there's plenty of dynamic range.
>
> Also, if you are interested, we are using Xilinx DSP48E1 blocks which use
> an 18x25 multiplier and so Xilinx tools generate the on-board DDS as a
> 25-bit DDS by default --- again to preserve the SFDR of the receiver. We
> could add extra bits, but 25 are fine for the same reason.
>
> Steve
>
> Stephen Hicks, N5AC, AAR6AM
> VP Engineering
> FlexRadio Systems™
> 4616 W Howard Ln Ste 1-150
> Austin, TX 78728
> Phone: 512-535-4713 x205
> Email: steve at flexradio.com
> Web: www.flexradio.com

On 5/19/2012 8:11 PM, Joe Subich, W4TV wrote:

>
> Decimation can help but it is not a magic bullet that eliminates
> the effects of ADC overflow and/or blocking due to gain reduction.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 5/19/2012 7:57 PM, Tom Azlin N4ZPT wrote:
>> decimation counts
>>
>> On 5/19/2012 7:29 PM, Joe Subich, W4TV wrote:
>>> The issue will be the severely limited dynamic range of the 16 bit
>>> ADC. Without effective AGC ahead of the ADC there *will* be overload
>>> problems on crowded bands (e.g. 160/80/40) where any transceiver must
>>> deal with many extremely strong ("local") signals while maintaining
>>> maximum sensitivity. With AGC, the strong local signals will cause
>>> "blocking" as the gain is reduced to prevent overflow of the ADC.
>>
>> ______________________________________________________________
>> 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
>>
>
>

N8MSA

Re: OT: Dayton New Equipment Show

In reply to this post by Joe Subich, W4TV-4

Direct digital conversion radio receivers rarely connect the A/D "directly" to the antenna input, the term "direct" referring to a lack of analog frequency conversion (mixing). The Flex 6000 series is no exception to this trend. There is a gain and filter stage ahead of the A/D, and presumably an AGC.

This is how dynamic range is managed on this, and many similar receivers. Blocking is a concern, but not even the greatest concern. Analog signal levels should, regardless of the number of discrete measurement steps ("bits"), should be kept well above the minimum input level to avoid excessive quantization error levels.

Mike Alexander - N8MSA

[hidden email] ----- Original Message -----
From: "Joe Subich, W4TV" <[hidden email]>
To: [hidden email]
Sent: Saturday, May 19, 2012 7:29:24 PM
Subject: Re: [Elecraft] OT: Dayton New Equipment Show

The Flex 6000/6700 is an "on frequency" direct digital conversion
radio - that is a 16 bit analog to digital converter operating at
the "front end" of the radio with no intermediate conversion/IF
and filtering stages. In addition, all of the DSP is contained
in the radio (no more PowerSRD). The new software for the Flex
6000/6700 (reportedly "PowerRX") is essentially a "glass control
panel").

A general purpose computer is required for PowerRX but communication
between the computer and transceiver is via TCP/IP which means the
computer can be anywhere. Audio input and output will be available
both on the transceiver and from PowerRX (interesting for remote
operation scenarios).

The issue will be the severely limited dynamic range of the 16 bit
ADC. Without effective AGC ahead of the ADC there *will* be overload
problems on crowded bands (e.g. 160/80/40) where any transceiver must
deal with many extremely strong ("local") signals while maintaining
maximum sensitivity. With AGC, the strong local signals will cause
"blocking" as the gain is reduced to prevent overflow of the ADC.

The new Flex design is certainly "interesting" but may not truly be
ready for critical "real world" use with the widely varying signal
levels in amateur service.

73,

... Joe, W4TV

On 5/19/2012 3:43 PM, Tony Estep wrote:

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Joe Subich, W4TV-4

Re: OT: Dayton New Equipment Show

In reply to this post by wb4jfi

On 5/19/2012 8:08 PM, [hidden email] wrote:
> Joe, I'm not sure some of your suppositions are correct.

Actually it depends on one's assumption of the number and strength
of the signals applied to the front end. 120 dB of spurious free
dynamic range is trivial if one is measuring it with *two tones*.

However, when one has five or six -33 dBm "local signals" (easy
on 160 or 80 meters during a major contest ... or 40 meters in
Europe with the superpower broadcasters just outside the band)
the required signal handling is many orders of magnitude higher
than just two -23 dBm (S9+60 dB) signals. Instantaneous peak
voltages do not add linearly ... they add exponentially.

Even with decimation the peak voltage to the ADC can not be allowed
to cause an overflow. In addition, one must be concerned about Herr
Nyquist ... and minimum sample rates for the highest operating
frequency.

73,

... Joe, W4TV

On 5/19/2012 8:08 PM, [hidden email] wrote:

> Joe, I'm not sure some of your suppositions are correct.
>
> First of all, the ADC samples at a significantly higher rate than the
> incoming RF (for HF), at 245.76MHz. Then, those samples go through
> decimation inside Digital DownConverter (DDC) in the FPGA, and the
> higher the decimation, the more the processing gain, and therefore added
> "bits". I believe the typical assumption is that you gain the equivalent
> of approx. one-half bit (3dB) of dynamic range every time you decimate
> (divide) the sample rate by two. This is real gain, not some imaginary
> trick or magic. If you start with a 245.76MHz sample rate, and end up
> with 240kHz (example), you could achieve a processing gain of an
> additional five bits, or 30dB. If my quick math is correct. All without
> AGC or other games.
>
> Throw away at least one A/D bit, so 15 bits(ADC) plus five bits(proc
> gain) yields 20 bits, or about 120dB of dynamic range. I must be a
> little off, as I saw one note on the Flex reflector that they think
> 153dB or so of dynamic range. Maybe by lowering the final sample rate
> some more, or not tossing all of one bit of the ADC. I believe Mitola
> suggested that 130dB of dynamic range is adequate for HF, I'm not sure
> if that includes noise from storms, etc. BTW, the new software is called
> SmartSDR.
>
> I have been playing with DDC receivers for a couple of years now, and I
> firmly believe they will be the future. I suggest that thorough research
> of DDC-based receiver design will alter your perception. It did mine.
>
> I love my K3/P3, and do not plan to replace it anytime soon. It just
> works GREAT, and is a nice compact box without requiring a computer to
> use. But, I was very tempted to by a Flex 6500. That is, until I saw the
> $200 per year charge for the software. Technically, very leading edge.
> Marketing, you decide.
>
> Hope this isn't too off-topic.
> 73,
> Terry, WB4JFI
>
>
>
> -----Original Message----- From: Joe Subich, W4TV
> Sent: Saturday, May 19, 2012 7:29 PM
> To: [hidden email]
> Subject: Re: [Elecraft] OT: Dayton New Equipment Show
>
>
> The Flex 6000/6700 is an "on frequency" direct digital conversion
> radio - that is a 16 bit analog to digital converter operating at
> the "front end" of the radio with no intermediate conversion/IF
> and filtering stages. In addition, all of the DSP is contained
> in the radio (no more PowerSRD). The new software for the Flex
> 6000/6700 (reportedly "PowerRX") is essentially a "glass control
> panel").
>
> A general purpose computer is required for PowerRX but communication
> between the computer and transceiver is via TCP/IP which means the
> computer can be anywhere. Audio input and output will be available
> both on the transceiver and from PowerRX (interesting for remote
> operation scenarios).
>
> The issue will be the severely limited dynamic range of the 16 bit
> ADC. Without effective AGC ahead of the ADC there *will* be overload
> problems on crowded bands (e.g. 160/80/40) where any transceiver must
> deal with many extremely strong ("local") signals while maintaining
> maximum sensitivity. With AGC, the strong local signals will cause
> "blocking" as the gain is reduced to prevent overflow of the ADC.
>
> The new Flex design is certainly "interesting" but may not truly be
> ready for critical "real world" use with the widely varying signal
> levels in amateur service.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 5/19/2012 3:43 PM, Tony Estep wrote:
>> On Sat, May 19, 2012 at 11:53 AM, Edward R.
>> Cole<[hidden email]>wrote:
>>
>>> ...website now shows the Flex-6000/6700 newest entry into the SDR
>>> market....
>>
>> ===========
>> Said to be digital from antenna connector to output. Their hardware has
>> long needed updating, so perhaps this will be it. However, Flex's really
>> weak link has always been their software/systems integration, so it
>> remains
>> to be seen if this does anything to mitigate that.
>>
>> Tony KT0NY
>>
>>
>>
> ______________________________________________________________
> 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
>

Joe Subich, W4TV-4

Re: OT: Dayton New Equipment Show

In reply to this post by Tom Azlin N4ZPT-2

> Guess we will have to await independent testing. The Flex folks seem
> to assert they have the equivalent of more than 24 bit when dealing
> with adjacent strong signals.

Yes we will need to wait for independent testing but given relatively
wide filters (200 KHz or more), that testing can't be done with only
two signals. The tests will need to be (notched) noise power tests or
multiple tone tests that stress the *total* power handling capability
of the system.

It is the huge increase in instantaneous peak voltage when multiple
signals are present that causes multi-channel (multiplexed) power
amplifiers to be rated for peak powers as much as 20 dB higher that
their average operating (output) power. The same problem of peak to
average power (voltage) *will* impact the absolute voltage handling
requirements of the ADC used in any DDC system. Decimation may
improve resolution but not the absolute maximum and minimum signal
levels.

73,

... Joe, W4TV

On 5/19/2012 8:23 PM, Tom Azlin N4ZPT wrote:

> Hi Joe,
>
> Guess we will have to await independent testing. The Flex folks seem to
> assert they have the equivalent of more than 24 bit when dealing with
> adjacent strong signals.
>
> From the Flex reflector...
>
>> Just in rough numbers, you get a 1/2-bit for every divide-by-two decimation
>> you do. If you are looking at dynamic range in a 500Hz bandwidth (this is
>> what we typically do). The math I generally use to get there is
>> log(f1/f2)/log(2)/2. I just think this way as a programmer (do everything
>> in base 2). So if you take log(245.76E6/500)/log(2)/2 you get 9.4 extra
>> bits when added to the 16 gives you 25.5 bits (152.7dB dynamic range).
>> This assumes all 16-bits of the ADC are "good" which is probably not a
>> good assumption. I'd have to pull out the notes and look at the data sheet
>> again, but this should give you a rough idea. Hopefully I haven't made an
>> additional "duh" today myself!
>>
>> Bottom line -- there's plenty of dynamic range.
>>
>> Also, if you are interested, we are using Xilinx DSP48E1 blocks which use
>> an 18x25 multiplier and so Xilinx tools generate the on-board DDS as a
>> 25-bit DDS by default --- again to preserve the SFDR of the receiver. We
>> could add extra bits, but 25 are fine for the same reason.
>>
>> Steve
>>
>> Stephen Hicks, N5AC, AAR6AM
>> VP Engineering
>> FlexRadio Systems™
>> 4616 W Howard Ln Ste 1-150
>> Austin, TX 78728
>> Phone: 512-535-4713 x205
>> Email: steve at flexradio.com
>> Web: www.flexradio.com
>
>
> On 5/19/2012 8:11 PM, Joe Subich, W4TV wrote:
>>
>> Decimation can help but it is not a magic bullet that eliminates
>> the effects of ADC overflow and/or blocking due to gain reduction.
>>
>> 73,
>>
>> ... Joe, W4TV
>>
>>
>> On 5/19/2012 7:57 PM, Tom Azlin N4ZPT wrote:
>>> decimation counts
>>>
>>> On 5/19/2012 7:29 PM, Joe Subich, W4TV wrote:
>>>> The issue will be the severely limited dynamic range of the 16 bit
>>>> ADC. Without effective AGC ahead of the ADC there *will* be overload
>>>> problems on crowded bands (e.g. 160/80/40) where any transceiver must
>>>> deal with many extremely strong ("local") signals while maintaining
>>>> maximum sensitivity. With AGC, the strong local signals will cause
>>>> "blocking" as the gain is reduced to prevent overflow of the ADC.
>>>
>>> ______________________________________________________________
>>> 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
>>>
>>
>>
>
> ______________________________________________________________
> 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
>

Don Wilhelm-4

Re: OT: Dayton New Equipment Show

I believe Joe is trying to say that traditional test methods fall short
of reality when applied to direct sampling SDR receivers, and I would
believe he is correct - there are too many "other factors" to be
considered (and some of them are yet unknown to most of us).

73,
Don W3FPR

On 5/19/2012 8:57 PM, Joe Subich, W4TV wrote:

>> Guess we will have to await independent testing. The Flex folks seem
>> to assert they have the equivalent of more than 24 bit when dealing
>> with adjacent strong signals.
> Yes we will need to wait for independent testing but given relatively
> wide filters (200 KHz or more), that testing can't be done with only
> two signals. The tests will need to be (notched) noise power tests or
> multiple tone tests that stress the *total* power handling capability
> of the system.
>
> It is the huge increase in instantaneous peak voltage when multiple
> signals are present that causes multi-channel (multiplexed) power
> amplifiers to be rated for peak powers as much as 20 dB higher that
> their average operating (output) power. The same problem of peak to
> average power (voltage) *will* impact the absolute voltage handling
> requirements of the ADC used in any DDC system. Decimation may
> improve resolution but not the absolute maximum and minimum signal
> levels.
>
> 73,
>
> ... Joe, W4TV
>
>

Bill W4ZV

Re: OT: Dayton New Equipment Show

In reply to this post by Joe Subich, W4TV-4

These were my questions Friday based on the published data sheet:

Questions for someone at Flex's Dayton booth:

"Except for the most demanding large signal conditions, Slice
Receivers are free to operate in wide-band mode without the need
for RF pre-selection filters."

1. What does "most demanding" mean?

"Further, the
dual Spectral Capture Units can be optimally combined on the
FLEX-6700 and FLEX-6700R to increase Blocking Dynamic Range
up to 3 dB and IMD DR3 up to 2 dB."

2. Increase BDR 3 dB better than what? (nothing spec'd on Data Sheet)

http://www.eham.net/ehamforum/smf/index.php/topic,82993.30.html

No answers yet...

73, Bill W4ZV

Geoffrey Mackenzie-Kennedy-3

Re: OT: Dayton New Equipment Show

In reply to this post by Joe Subich, W4TV-4

It will be interesting to hear if the Flex 6000/6700 when used in Europe can
deal with the European 40m BC stations.

Some data.

Over a period of several months when I was in Scotland, I measured the level
of these 40m BC signals with which a receiver must cope. Using a 40m dipole
at 70ft AGL firing N-S, not a beam, the level of the -carrier- of most of
the European 40m BC stations at the shack end of the feeder would reach + 5
to +10 dbm under "normal" conditions of propagation.

And there were many BC signals of similar strength "on air" at the same
time.

In this part of Europe the 40m BC signals are not as strong, probably due to
being closer to the BC transmitters, which could benefit Flex's sales in
Europe.

73,
Geoff
LX2AO

On May 20, 2012 at 2:46 AM, Joe Subich, W4TV wrote:

<snip>

> However, when one has five or six -33 dBm "local signals" (easy
> on 160 or 80 meters during a major contest ... or 40 meters in
> Europe with the superpower broadcasters just outside the band)
> the required signal handling is many orders of magnitude higher
> than just two -23 dBm (S9+60 dB) signals. Instantaneous peak
> voltages do not add linearly ... they add exponentially.

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SP600JX21A

Re: OT: Dayton New Equipment Show

In reply to this post by Edward R Cole

Well, when Flex starts charging for software updates. That alone will
kill future sales. With all the hype on how great their new lineup is,time will
tell. We all know what is on paper and what happens in the real world can
be completely different. They learned that you need a dedicated high
performance PC to work the software. That was proven from their users with all
those problems I have seen on their reflector. At least Elecraft has a proven
record of great products.

Charlie
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Phil Hystad-3

Re: OT: Dayton New Equipment Show

But then, we may be witnessing another change in the evolution of ham radio where the added value to a rig is in the software and not the hardware. By licensing their SmartSDR, Flex may be realizing that the key factor separating them from the other emerging SDRs lies with their software and not the hardware components. In particular, their DSP as well as the visual user interface.

So, the future SDR rig may indeed be the software you load on your computer and the hardware component is nothing but a mere commodity that you pick up from an SDR vendor or throw together yourself. After all, once the key parts of an SDR hardware are made available as various ADC ICs and other components then there is only the software to deal with.

I submit that this is indeed the future of ham radio where your new rig is something you download from a software vendor rather then buy at HRO.

My two-bits.

73, phil, K7PEH

On May 20, 2012, at 9:33 AM, [hidden email] wrote:

> Well, when Flex starts charging for software updates. That alone will
> kill future sales. With all the hype on how great their new lineup is,time will
> tell. We all know what is on paper and what happens in the real world can
> be completely different. They learned that you need a dedicated high
> performance PC to work the software. That was proven from their users with all
> those problems I have seen on their reflector. At least Elecraft has a proven
> record of great products.
>
> Charlie
> ______________________________________________________________
> 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