Love to see a comparison...

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  • Updated 4 years ago

Just saw this Youtube comparing the older IC-7800 vs the new IC-7851, showing a dramatic improvement in weak signal blocking on CW.

https://www.youtube.com/watch?v=-sVpoPJKgo8


I'd really love to see a comparison with the Flex-6K series. Any takers?

(All of these rigs require a new mortgage on the house...)

- 73 de Dave, N7AIG


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N7AIG

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Posted 4 years ago

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KY6LA - Howard, Elmer

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Sort of done that already at our contest station NX6T in the Spring


We have several K3S, a KX3, my 6700, An IC-7850 and virtually every other top of the line Kenwood and Yaesu.

Mostly we use the K3 in contests ..enough said,,albeit you can read about our humorous various contest shootouts withe the K3, KX3, 6700 and 7850 in my reports last November.


Bottom line even the $1K KX3 SDR outperformed the 7850 so it sits on a back shelf waiting for some octogenarian who demands the best Icom to contest with


A Vendor ..knowing we buy the best of everything lends us radios to,try all the time. So they lent us a 7851 to try during a contest


The 7851 looks like a 7850 ..it's very big and klunky. It takes up the whole desk and is not ergonomically optimized for contesting because it's large size interfere with keyboard and monitor layouts for the contest loggers.


As I said, we have a 7850 but being 10+ year old Legacy Technology even our $1K KX3 SDR outperforms it so no one ever uses it ,,,


From what I could see all Icom did with the 7851 was improve the phase noise internal local,oscillators so that it approaches but definitely does not beat the 6700. It is a definite improvement over the 7850 BUt it's Legacy Texhnology and there is only so much you can do to tweak it even when you spend a lot of money


It went back after the contest,,,No one was impressed. The K3S was still much better for contest ergonomics. The 6700 heard better,,,but I admit to being biased.


It lists for. $16,999 but is already being discounted to $14,499. It's a perfect Legacy Radio for an Octogenarian who wants to spend his grandkids inheritance.
(Edited)
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Walt - KZ1F

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Gee Howard, I thought the goal of this was to always have your last check bounce. Is that not so????? ;-)
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KY6LA - Howard, Elmer

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Of course. My goal is spend it all before I die and sponge off my kids for the last bit.
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Sergey, R5AU

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Just for the next step : example with SunSDR 2 from Yurj UT4LW https://m.youtube.com/watch?v=AQioPNE...
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Sergey, R5AU

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Das anybody doubt with the Flex 6000 abilities ?
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ka7gzr

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Howard,

I think you mean a "7800" not a "7850" when referring to Icoms legacy radio. The 7850 is a limited version (only 150 produced) but is electrically the same as the 7851. By the way, I own both a 7850 and a 6700. Maybe I should get a K3s to round my collection out. :)

Jim

ka7gzr

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KY6LA - Howard, Elmer

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Correct
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N7AIG

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Interesting comments... did some more thinking about the hardware architectures...

Is it fair to state that the BDR shown in the IC-7851 is limited by mixer IMD against the (even cleaned up) LO? And that DDC does not suffer these limitations because no mixing is occurring? LO cleanliness isn't as important for DDC as for conventional heterodyning?

( I viewed some SUNSDR2 Youtube clips - impressive performance. So I'd expect the Flex-6K to behave similarly? )

( I suppose I should actually try some tests with my Flex-3K and Flex-1500 too. Maybe they already perform better than the IC-7851? )

73 de Dave, N7AIG

(Edited)
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KY6LA - Howard, Elmer

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All radio,designs today are basically limited by their phase noise

Reading the specs. The 7851 has better phase noise than the 1500 or 3000 which are both First Generation Direct Conversion SDR so they have Mixers too

By contrast the 6000 is a ThirD Generation Direct Sampling SDR
(Edited)
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ka7gzr

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Another siteĀ  to visit for test reports of the Flex 6700 and Icom IC-7851 is Adam Farson, VA7OJ.

For the 7851 go here:

http://www.ab4oj.com/icom/ic7850/7851notes.pdf

and the 6700 go here:

http://www.ab4oj.com/sdr/flex/6700rev1_38_notes.pdf

Jim