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Author Topic: New FlexRadio 6000 Announced  (Read 59417 times)
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W3RSW
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Rick & "Roosevelt"


« Reply #50 on: May 20, 2012, 02:16:20 PM »

The LTC 2208 comes in two, right up front, flavors or packages.
The orig. LTC 2208 is 16 honest bits and the LTC2208-14, is the 2208 lite flavor.

So how does oversampling work for 4 missing bits?   Time.
-The added dimension if done properly.

Steve,
All humans are tribal, built into the genes; civilization is the altruisic, group effort to overcome hedonistic, self greed.  A good part of altruisim is honesty.  A team works better with transparancy.  I suppose that can be interpreted or spun in both conservative and liberal ways.

Besides, "my radio is better than yours" is fun and we like it.  We like being informed and learning when possible.   Many of us have tons of radios which we all like for various purposes, some just 'cause they're pretty or have black crackle, or...     

I admire your propensity to keep things on track, logical and based on the trivium where possible... but being human is fun too.
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RICK  *W3RSW*
Steve - K4HX
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« Reply #51 on: May 20, 2012, 02:43:41 PM »

I hear ya Rick. Not denying anyone being human. I just don't think any of this mine is better than yours crap adds anything of value to the conversation. Until rigorous measurements are made, all the rest is just prepubescent chest thumping. The reality is that most of these ballyhooed specs make ZERO difference in 99% of amateur radio operation. In other words, they are irrelevant and it follows chest thumping about them is also irrelevant.
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K3ZS
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« Reply #52 on: May 20, 2012, 02:45:34 PM »

You can increase the dynamic range of a system by oversampling and dithering even if the A/D does not have the dynamic range, this was used with radar 10 to 20 years ago when the best high speed A/D converters were 8 bits.    Usually the signal riding on noise provides a natural dithering and the higher speed of the A/D provides for the oversampling or signal integration.   When coherently integrating I and Q channels the noise is reduced by the square of the number of samples integrated.    It really works.
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W3RSW
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Rick & "Roosevelt"


« Reply #53 on: May 20, 2012, 03:36:15 PM »

Does this not require extra clock cycles in comparison with having the additional parallel processing four bits?
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RICK  *W3RSW*
K3ZS
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« Reply #54 on: May 20, 2012, 04:27:51 PM »

Not sure what Flex uses.    With the radar, if you are using coherent integration, you take many samples of the I and Q channel and integrate each by itself, the result is a single I and Q value.   Do this many times and use the values in the processing.    The result is wider dynamic range if all the
samples in the I and Q are independent.    Also the spectral bandwidth is reduced and the signal to noise ratio is increased.    This requires higher sampling rates and wider bandwidth as compared to just one-to-one sampling.    If you can't oversampled then you are limited by the number of bits in the a/d converters.  I would like to see what type of processing they are doing in the flex with all this radar signal processing being applied to ham radio.
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WA1GFZ
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« Reply #55 on: May 20, 2012, 04:59:44 PM »

So you take the 2208 with 16 honest bits and sample at 122 or 130 MHz then compare it to a 12 bit machine running at 245MHz, where is the gain. You only need to divide it by 2 one more time.
There is no chest thumping here Steve just wondering what is the true performance.
I follow all new A/Ds that come out, kind of a hobby. the 2209 is the only one close to being better. LTC still seeems to be the best for us guys on the street.
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Steve - K4HX
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« Reply #56 on: May 20, 2012, 09:19:26 PM »

Lots of chest thumping. Let's review.

Quote
Heck I bet the 5 year old 14 bit Perseus is a better radio.
Sorry it burst the bubble and set off the BS detector

Quote
But they will pump the sampling rate to the fools.

Quote
Get the sucker hams to pay for beta testing and do the testing for free then market to the mil guys for big bucks

Quote
I'm into my dual RX HPSDR for under $1500
16 bits 122 MHz sample


You've never used the radio and have no measurements to go on, yet you've claimed it's marketed at fools. By way of contrast you proudly proclaim how little you've spent on your set up. Sounds like chest thumping to me. The reality is that most of these ballyhooed specs make ZERO difference in 99% of amateur radio operation.

I've made something like 6000 contacts over the past few years. I've heard tons of Flex radios but only one or two HPSDRs. If they were so great, I would expect to hear more on the air.
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K1JJ
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"Let's go kayaking, Tommy!" - Yaz


« Reply #57 on: May 20, 2012, 09:27:39 PM »

Overheard at Dayton this weekend:

"This flex-girdle is killing me!"


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Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

Wise Words : "I'm as old as I've ever been... and I'm as young as I'll ever be."

There's nothing like an old dog.
Steve - K4HX
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« Reply #58 on: May 20, 2012, 09:33:59 PM »

Over sampling also allows you to move what would normally be in-band noise up in frequency out of band. It's been done in audio A/D for decades. In fact, nearly all A/Ds in audio gear since the 90's have been using a 1-bit delta sigma converter and oversampling. This arrangement can produce up to 24 effective bits.


Not sure what Flex uses.    With the radar, if you are using coherent integration, you take many samples of the I and Q channel and integrate each by itself, the result is a single I and Q value.   Do this many times and use the values in the processing.    The result is wider dynamic range if all the
samples in the I and Q are independent.    Also the spectral bandwidth is reduced and the signal to noise ratio is increased.    This requires higher sampling rates and wider bandwidth as compared to just one-to-one sampling.    If you can't oversampled then you are limited by the number of bits in the a/d converters.  I would like to see what type of processing they are doing in the flex with all this radar signal processing being applied to ham radio.

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WA1GFZ
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« Reply #59 on: May 20, 2012, 09:42:04 PM »

if you claim to be the best you should be the best
An 813 isn't a 4-1000A.
And yes I have operated the Flex 5000.
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Steve - K4HX
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« Reply #60 on: May 20, 2012, 09:46:06 PM »

You haven't operated or made measurements on a Flex 6000, the topic of discussion here.

You've provided nothing that shows Flex isn't the best, just some meaningless A/D specs.
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Bill, KD0HG
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304-TH - Workin' it


« Reply #61 on: May 20, 2012, 09:49:30 PM »

I'll still take my R-390 A.

Bill
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Steve - K4HX
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« Reply #62 on: May 20, 2012, 10:01:53 PM »

22 receivers ahead of the 390A on the Sherwood list, including the Atlas XL350 from the 70's. WTF?
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WA1GFZ
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« Reply #63 on: May 20, 2012, 10:03:15 PM »

Flex has not provided any specs either and they are hoping to sell the thing
for large money.
I have only an interest in performance. So the first thing that I checked was one of the most important components and it doesn't add up.
I do think it has some cool processing and a better front end than the 5000 and HPSDR for that matter.
But IMHO the A/D looks pretty sloppy. ENOB now that is an interesting term.
150 counts of offset another.  

There are only about 400 HPSDR rigs world wide and I bet 1/2 are not on the air in TX. Most run low power. Heck, I just hit 1200 Watts PEP last week.
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WA1GFZ
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« Reply #64 on: May 20, 2012, 10:06:16 PM »

Drop some high level balanced mixers in a R390 and I bet it would climb up a bunch of notches. Still one of the cleanest LOs on the planet.
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W1VD
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« Reply #65 on: May 21, 2012, 08:27:25 AM »

Definition of ENOB about half way down ...

http://www.analog.com/library/analogDialogue/archives/40-02/adc_noise.html

Frank ... your TX sounded excellent last night ... about the best you've ever sounded.  No carrier glitches noted.
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'Tnx Fer the Dope OM'.
WA1GFZ
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« Reply #66 on: May 21, 2012, 09:37:42 AM »

Good reading Jay.
Notice the 9467 part spec is 95 dBFS NFDR at 250 MSPS and does not increase to 100 dB until you drop to 160 MSPS.
It would be interesting to see a FFT of the output to see what it does with all these extra samples.
Time will tell when real specs are released.
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Jim KF2SY
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« Reply #67 on: May 21, 2012, 12:15:34 PM »


Maybe some chest thumping here:


http://www.youtube.com/watch?v=DMoWt0wnlUw

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Todd, KA1KAQ
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« Reply #68 on: May 21, 2012, 12:37:46 PM »

Mine is better. All others are junk. Anyone who has one of "those radios" is a fool.

No surprise considering the online mentality for such arguments vs. real life. Brag, belittle, or otherwise thump your chest at a hamfest or on the air and a handful of people might hear you. Do it online and hundreds, potentially thousands could be exposed to it. As we've seen, that's what is truly important to some, not the reality of actual use and utility. The critical discussion is fascinating to read, but as to the P&Ming, you're right - it brings nothing useful to the table and gets old pretty fast.

Um, the website says, "Your On-Line Guide to AM and Vintage Radio"  so what did you expect?  

Someone has to convince me there's something vintage about the Flex Radio.  Good luck.

Rob, you should read this as AM (whatever you choose to operate the mode with) and Vintage Radio. Rather than an exclusive site for vintage AM, it's all-inclusive for AM specifically.

I'm an old gear buff myself and, for all its faults, never see that interest waning. I've never been particularly interested in plastic radios or especially the newer computer-based SDR stuff. I enjoy working both on the air, though. As great as they sound, I could be listening to a plate modulated broadcast transmitter. I can't see 'em, sooo..... Wink

In the last few years a number of things have happened to pique my interest in SDR. First was a thread that G started on here about the Softrock application for his R-390A. Then I got to see a new-ish receiver with panadaptor and other excellent features at Steve/K4HX's station. Then earlier this year or late last, Rob/yAEX posted some samples of signals he'd received during the HMR, including what my signal looked like. Finally, after NEAR-Fest on our way south, Steve and I were treated to a demo of Chuck/K1KW's new station which absolutely amazed me. An excellent visual of what we were hearing.

So, while I'm not in the market at this point for anything 'new', I have developed a distinct appreciation for its utility. Hell, I just got a decent scope hooked up as a mod monitor in recent years. But I can certainly envision a time in the future where some of this SDR-type stuff could be very handy in conjunction with the current big iron here. Beyond the more typical features-for-the-sake-of-more like endless memories, this is stuff that is really handy for AM.

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known as The Voice of Vermont in a previous life
K3ZS
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« Reply #69 on: May 21, 2012, 02:01:34 PM »

My own preference is to use simple rigs with analog filters, but the Flex radios, as a group, have the best sounding AM modulation heard on the ham bands.
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K6JEK
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RF in the shack


« Reply #70 on: May 21, 2012, 02:04:44 PM »


I'm an old gear buff myself and, for all its faults, never see that interest waning. I've never been particularly interested in plastic radios

...
I'm gaining a real appreciation for radios that don't hurt my back when I lift them
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KB2WIG
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« Reply #71 on: May 21, 2012, 02:17:20 PM »

Man was borne to suffer.


klc
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What? Me worry?
WA1GFZ
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« Reply #72 on: May 21, 2012, 09:07:30 PM »

http://en.wikipedia.org/wiki/ENOB

as I lernt it. A trick the sound card guys played with early 24 bit audio A/Ds that actually had a hard time making 18 bits.
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KD0HUX
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« Reply #73 on: May 21, 2012, 11:29:52 PM »

I'll still take my R-390 A.

Bill
Cool Cool Cool Cool Cool Cool Cool Cool Cool
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kb3rdt
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poop cup


« Reply #74 on: May 21, 2012, 11:58:10 PM »

Maybe best to Zip it!


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