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Author Topic: Flexradio Dayton Surprise: $2499 Radio in 6000 Family  (Read 20000 times)
W3RSW
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Posts: 193




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« Reply #30 on: May 12, 2014, 08:27:40 AM »

9oy,
Was typing away while you posted.

Yeah, right about the front end.  --that's why the 6300 receiver is more than adequate for 99%  of operations.
Also for all such DDC SDR's, Once you see all around you and other bands to boot, there's no going back unless for nostalgia and focused application.

-Rick
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W9OY
Member

Posts: 1357


WWW

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« Reply #31 on: May 12, 2014, 09:34:18 AM »

K0OD

http://sdr-w9oy.blogspot.com/2014/05/there-was-question-on-eham-how-6300s.html

I added a little more info to last nights post to give a little more idea of how the radio operates and its usefulness.  If you right click the pics and open in a new tab you can mag the pic to get the full effect.  In some pics I am shooting across 2 HD screens so the pics get kind of shrunk down

73  W9OY
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N8VB
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Posts: 21


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« Reply #32 on: May 12, 2014, 09:59:42 AM »

When the QS1R first came out and did not have front end band pass filters I remember I took a lot of grief and insult.  Eventually things settled down and there is a better understanding of DDC receivers now.  I am not saying that a DDC receiver can not benefit from band pass filters, because in the right circumstances they can and do.  Flex purchased a QS1R back in 2010 and I am hoping that it played some part in their decision to come out with the new 6000 series as far as seeing that DDC receivers perform well, at least up there with some of the other well thought of analog front end rigs on the market today.

For those who are obsessed about transmitter IMD and the 12 V PA does not satisfy you, I would think you could use the 6000 series transverter port to drive your own design amp chain and achieve the IMD you want.   I am guessing the transverter output comes directly from the TX DAC used on the 6000 series, and that is very clean.
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W9OY
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« Reply #33 on: May 12, 2014, 12:31:28 PM »

Phil

I think you are right about the transverter.  I think the output of that port is on the order of a few + dBm.  I know the amp has its own software control and I presume it can change its class etc under software control so you would probably loose something (like predistortion) when stuff like that comes on-line.  The signal can be sensed at various stages and used for feed back.  Software manipulation of the amp was possible as far back as the SDR-1000.  At one point I was playing around with class A with that rig poking values by hand into deeply hidden menus.  When the update firmware is loaded there is a part of the upload that goes to the amp.  You can tell because the fans start going nuts and then the thing does a midway re-boot on its own.

As far as the QS1R people gave you a hard time about a lot of things like doing SDR over USB etc.  Picking the right port for communication with the computer turns out to be a big deal as far as longevity and performance goes.  I think many people learned a lot from the design of that radio.  I spoke to Gerald K5SDR at Orlando in Feb. and he said much of the architecture at least conceptually came from their commercial spy radio.  We talked about this type of FPGA/DDC as far back as about 2004 back when W5GI was still alive but then the cost of components vs performance was prohibitive.   I am so glad it has come to fruition and for me its all great fun.  I hope you enjoy your radio as much as I have enjoyed mine.

73  W9OY
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M6GOM
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Posts: 1012




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« Reply #34 on: May 12, 2014, 04:34:01 PM »

I guess Zenki's point just does not resonate here. He does not like any rig that has poor transmit characteristics. Brand does not matter. Icom, Yaesu and Kenwood have successfully manufactured
50v systems with clean transmitters. If you have a sdr, you can plainly see the difference of a 50v transmitter vs a 12v transmitter on your waterfall. They have a different luminous look.


The point you miss is that you don't have to have 50V finals to have a clean signal on SSB. By using Adaptive Predistortion you can make a 13.8V PA as clean as a 50V PA.

Flex 6000 series have all the hardware in place for adaptive predistortion and just need to find the best algorithms to implement it in the software.

From Steve N5AC the VP of Engineering:

Quote
When we designed the FLEX-6000 we had adaptive predistortion in mind so we included a tap from the transmitter that feeds back into the receiver. This gives us simultaneous access to the desired and actual transmit spectrum in the FPGA so that we can implement linearizarion. We also have sensors for temperature, voltage and load match of the PA as these can be used to improve linearizarion. The work that needs to be done for the FLEX-6000 is to experiment with algorithms and input sources to determine what gets us the most bang for the buck and then finalize the implementation.

A 50V PA does not guarantee low IMD.
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K5TED
Member

Posts: 809




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« Reply #35 on: May 13, 2014, 05:37:53 PM »

"'If you have a sdr, you can plainly see the difference of a 50v transmitter vs a 12v transmitter on your waterfall. They have a different luminous look."  Cheesy
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K0OD
Member

Posts: 2591




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« Reply #36 on: May 13, 2014, 06:44:58 PM »

If you have a sdr, you can plainly see the difference of a 50v transmitter vs a 12v transmitter on your waterfall. They have a different luminous look.
My favorite one is the Icom 7700 cw signal. You can just see it plain as day.
Greg kc8iir

Hey, I want to look luminous on waterfalls, not like a mousy 12v Flex-5000 Smiley.  My wife just bought some expensive makeup from Home Shopping Network that's supposed to make her look luminous. That must be the marketing buzzword of 2014. Ya'all agree with KC8IIR?

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ZENKI
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Posts: 989




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« Reply #37 on: May 14, 2014, 02:53:35 AM »

Whatever the  road  taken is towards  reducing  transmitter IMD and splatter it will be well worth it for all concerned

You can use a severely underrated 12 volt PA and achieve excellent IMD performance without even using pre-distortion.

The Anan uses a 12 volt PA and achieves good IMD performance when using pre-distortion.
The pre-distortion works wonderfully well with high voltage fets  because of the so called "memory effects"
Newer digital  pre-distortion methods includes the memory effect issue in the correction loop so may work very  well with 12 volt PA's
This technique  is now being used in LTE amplifiers. The technology is out there that can accommodate and deliver results regardless of what PA technology or topology you want to use.

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W3RSW
Member

Posts: 193




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« Reply #38 on: May 14, 2014, 06:45:13 AM »

Quote
You can use a severely underrated 12 volt PA and achieve excellent IMD performance without even using pre-distortion.

"Severely underrated"

I think you meant " minimally signal driven"  or possibly devices having far greater dissipation with attendant available power than normally required for the driving signal in the average  30 db down products amplifier.

Or both.

So yes, right.

Looks like pre-distortion tech will be the way most new designs will fall for a variety of reasons, e. g., economy of design,  parts stocking, commonality of boards, etc, for both mobile and home station applications.

Yes also, it's about time amplifiers get cleaner. Most have gotten or already knew your point. Strictly economics and marketing now.
There's a reason VHS won over Sony Beta. Technology didn't win the front seat. Sometimes that's the way it is.  The arguers for the "better" are lost in time.

So I think you'd be better served with recognition.  From time immemorial, once pen names of authors are discovered, they've always been better served by declaring.  Sometimes with their heads but as martyrs history treats them kinder  Grin.

Otherwise most all of us see you as the self serving thief of every and all posts having anything to do with amplification. Oh, yes, you long diatribe in "amplifiers section" just arrived.

Shame on us for falling into the endless reply loop.  You must feel extra special.
And of course the game of discovery robs and debases the intent of hams trying technical discourse in Eham.net.  I'm surprised the moderators haven't removed you.

-best regards,
-Rick
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W1JKA
Member

Posts: 1821




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« Reply #39 on: May 14, 2014, 07:14:17 AM »

Ouch !
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KC8IIR
Member

Posts: 112




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« Reply #40 on: May 14, 2014, 01:38:41 PM »

Man , i love reading the posts here. Thats absolutely(  ) what i love about eham sdr forum contributors. Absolutely (  ).

 Greg kc8iir.
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K9COX
Member

Posts: 58




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« Reply #41 on: May 16, 2014, 07:33:36 AM »

Flex is already out of 6300's and it is the first day of Dayton.
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W0FG
Member

Posts: 2




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« Reply #42 on: May 16, 2014, 05:55:32 PM »

It's 0230 UTC and I'm at the downtown Dayton Grand Hotel, unwinding with a good bottle of Irish whisky after a full day at Hamvention.  I'm looking forward to the banquet with the Flex company folks here tomorrow night.  I spent a couple of hours, off and on, around the Flex booth, expounding on my very favorable experience with my 6500, including a nice visit with Dave Sumner, K1ZZ, and watching the demos of SDR Bridge and CW Skimmer.   That's my next project, once we get back home on Monday.  I get a lot of laughs from this forum and the pure bull s#!t I see.   I visited the ANAN/Apache Lab 'booth' today too....a couple of Indian guys and a card table with no working demo.  The Flex booth, by contrast, was mobbed every time I walked by.  I really don't care whether I have 50v or 13v finals.  I could give a rat's @$$ about pre-distortion.  I know I've worked 170 countries since Christmas with my 6500, 95% on CW.  I know I get consistently excellent audio reports on the handful of SSB contacts I've made. (Coincidentally, almost all of them involved Flex-beam users, which will be my next serious project.)  I know I've worked nearly 30 countries on RTTY, a mode I haven't used since my S-Line/ST-6/Model 28 days in the 70s.  I know I can take my morning coffee down to the shack and watch the gray line on four bands, with four panadaptors all at once.  I'm 68 years old.  My last new radio was a Yaesu FT-757gxII in 1987.   The 6500 will most likely be the last new radio I buy  and I'm fine with that.  Sometimes reality trumps theory.....
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ZENKI
Member

Posts: 989




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« Reply #43 on: May 16, 2014, 09:31:06 PM »

So long as the problem is fixed.

Receiver performance would not be where it is today if there was debate or discussion about the poor state of receiver design performance in amateur  equipment.
Because of this lack of receiver performance debate  that occurred  a decade ago  you can buy a radio like the TS590S with such a good receiver for 1500 dollars. This certainly would not have happened if the topic was not hotly debated and discussed. Its a shame that the TS590S has such a poor transmitter. However  maybe in the next model Kenwood will do something about making the TS590S transmitter better. Shutting up and   not calling a spade a spade is not the way of getting design problems fixed.

Unfortunately hams  want to defend the junk that  they buy with religious fervor. If this same resentment and anger were directed towards the manufacturers about the poor transmitter performance and ALC spikes, maybe something would be done about the issue. Why do so many hams want to taken to the cleaners with overly expensive equipment that performs so badly? Whining and protesting would be a good way of making sure that these problems will be fixed.

There seems to be a lethargic complacent ham population that  want to pass off  brand shopping habits as technical research and intelligence because they payed X amount and that its better because they bought it. They will buy this poor performing equipment  despite  what the technical specifications says. Now when someone tells them that they bought something that is crap they get mad. When someone points  out the technical deficiencies of their equipment choices they get upset because they cant understand something as simple as  transmitter and receiver specifications and feel resentment when someone points to these deficiencies.. Those who want to define receiver and transmitter performance as a set of  feel good shopping decisions are very welcome to tell the engineering world how their feel good decisions is more important than technical merit assessment. I call that voodoo  and  it seems there are lot of hams who like believing in voodoo.   Worst still are the brand delinquents who  will say anything that  justifies their brand purchasing decisions. There seems to be more wanting  to hear accolades about what they bought rather than the technical truth. At the end of the day the transmitter engineering specifications do not tell lies. It seems only hams who want to perpetuate lies and pour accolades on equipment that has junk specifications.  I am confident in my position because any decent engineer  can verify the facts that just about all the current transceiver manufacturers produce equipment with poor transmitters.


Quote
You can use a severely underrated 12 volt PA and achieve excellent IMD performance without even using pre-distortion.

"Severely underrated"

I think you meant " minimally signal driven"  or possibly devices having far greater dissipation with attendant available power than normally required for the driving signal in the average  30 db down products amplifier.

Or both.

So yes, right.

Looks like pre-distortion tech will be the way most new designs will fall for a variety of reasons, e. g., economy of design,  parts stocking, commonality of boards, etc, for both mobile and home station applications.

Yes also, it's about time amplifiers get cleaner. Most have gotten or already knew your point. Strictly economics and marketing now.
There's a reason VHS won over Sony Beta. Technology didn't win the front seat. Sometimes that's the way it is.  The arguers for the "better" are lost in time.

So I think you'd be better served with recognition.  From time immemorial, once pen names of authors are discovered, they've always been better served by declaring.  Sometimes with their heads but as martyrs history treats them kinder  Grin.

Otherwise most all of us see you as the self serving thief of every and all posts having anything to do with amplification. Oh, yes, you long diatribe in "amplifiers section" just arrived.

Shame on us for falling into the endless reply loop.  You must feel extra special.
And of course the game of discovery robs and debases the intent of hams trying technical discourse in Eham.net.  I'm surprised the moderators haven't removed you.

-best regards,
-Rick
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M6GOM
Member

Posts: 1012




Ignore
« Reply #44 on: May 17, 2014, 05:06:57 PM »

Its a shame that the TS590S has such a poor transmitter. However  maybe in the next model Kenwood will do something about making the TS590S transmitter better.

They've already implemented a hardware fix in all 2014 production radios and are currently sending parts out to Kenwood service centres to retrofit to all existing TS590s.

With your claims about this and adaptive pre-distortion in the Flex 6000 series you're not keeping abreast of things are you? Please do try to keep up.  Wink
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