Flex 6400 vs 6600

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Is it worth the price difference for a non contester Ham? Are these models at base the same?
First of all I seriously consider going for the new 6400 with Maestro. I have played with Flex Radios at Hamradio Friedrichshafen (which is a shy of 180 miles from my house :-) very year. Excited but still a fear of a black box :-). I am just thrilled by the possibility to work remotely from a different room or somewhere else on these planet while the 6400/or 6600 sits at home QTH. It is also matching my purchasing possibilities, without the danger of rushing my XYL to Emergency Room when I will break the news about the new purchase :-). I have read on this forum though that new 6400 has a higher permanent S5 noise vs 6600 or more expensive models. I have also read stories about 6400 units failing to boot which send me to panic mode. I understand also the differences between new models.More radios so slices. Higher ADC sampling rate. No clue what exactly the Contest Grade Preselector as 3rd Grade vs 7th Grade really means for average Ham. But is it same RX quality on all models? I am currently using a Yaesu FTDX-3000 (with an AirsSpy HF+) , which I have to admit has one of the quietest receive performances out there for the price. My Ham habits are mainly hunting for DX stations and rarely participating in a contest for practice of my CW skills rather then for winning anything :-). So yes I am a CW man. Can anybody share an insight on these issues? Does anybody test FTDX3000 vs new 6400 side by side? Appreciate any answer or honest advice. Vy 73`s de DM1TX. A would be Flex user. Greetings  from Munich, Germany.
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Val DM1TX

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Posted 3 weeks ago

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WQ2H - Jim Poulette

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Hi Val,

My reasoning for the 6600M was 4 receivers, wider waterfall/spectral bandwidth, 4 Rx antenna inputs, and the tuner (which I don't use in the shack - but if I ever take it remote I probably will need it). On the "Rx quality" side - I never thought I'd use the diversity reception - but now it's rare when I don't use it for phone. Go figure! Here's the link to the comparison table: https://www.flexradio.com/comparison/

I've had it about 6 months, through a few upgrades, and have had no issues to speak of. With a tablet in the house remote SmartSDR works perfectly - bring it out on some public LAN or WiFi and you're basically on your own. It has run 24/7 here since the day it arrived. I use it for phone and digital of all descriptions. It also works nicely with an ALS-600 and many other amps. I moved from an FTDX-1200, and I find SmartSDR easier then the Yaesu menu/dial system. I love Yaesu, don't get me wrong (still have a FT-991 in my go-box), but the multiple receiver aspect of this was simply a better fit for me personally. Oh, and "contesting" is absolutely the LAST thing on my mind !

You do, however, have a point with the "XYL to the emergency room" problem......

What ever you decide, good luck!
73
Jim, WQ2H

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Michael Walker, Employee

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Hi Val

The 6400 is the best value HF rig available based on many things, a lot of it my personal experience.  Designed from the ground up to be used by multiple sources and applications and not limited by 1 RS232 port like all other current HF radios.

All of our 6000 series radios are contest grade/ready.  Not that you need it, but when you need a brick wall in the front end, you have it.   

In digital modes, I copy more than I have with any other radio.  Hands down.

Make sure you watch some of the videos on the FlexRadio YouTube channel.

73, Mike va3mw
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bahillen

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Val, I ordered the 6400. After investigating the comparisons I upgraded to the 6600. I am not a contester. I am thrilled with my decision. The main reason for my decision was that an antenna tuner is a must for me to protect the radio from my wire antennas withSWR across the band. 6600 includes tuner.

My intent was to get Maestro later. I see no need to do that. I operate the same way with SmartSDR regardless of P.O. cal or local remote.

Two SCUs help with using on two bands so you are not in wide mode with not frontend filtering. If working split with 6400 you have no other monitoring you can do. You don’t have to listen to monitor because you can see the panadapter to monitor band openings.

Many more features. Regardless you will enjoy either radio. I didn’t want to be looking to buy an upgrade to 6600 in a year or too.

73 W9JJB
Bill
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Bill -VA3WTB

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Val, if you were to look at a block diagram of the FTDX-3000 and  a Flex 6xxx radio you would notice the many inherant advantages the Flex has. A direct sampling reseiver as in the Flex is very sensitive. With the aid of the AGC-T witch other radios do not have, The Flex reciever can be made to be very quiet.
Sometimes when we say our older or non SDR radio's are so quiet it really means that radio is just not hearing as well as we think.

The Flex hears deep into the noise floor,, It hears everything..lol  So it may sound like it is noisy to some,  but this is what happens when a radio hears everthing, just look at the water fall for evedance of this.

The Panadapter display is the best in ham radio with it's smoothness and details. Invented by Gerald in the first place with PSDR and before he thought of a name for it.

The boot problems you read about are real. But Flex is looking into the cause. It will likely be a software fix because many are getting the radio to boot after doing something to them. And some may be hardware failure.

But When you buy a Flex you are buying very good customer support, know other company has a forum set up like this one were you can talk to other owners in real time.

I could fill this page with more, but It makes for too much reading I know.
Good luck...

Bill   VA3WTB
(Edited)
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EA4GLI - 8P9EH - Salvador

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Ken, I am not questioning that. I just think that we, as frequent posters here, should be more careful with our statements. I enjoy my 6700 panadapter and I appreciate many of the things Geral et al. have done with SDR for the hobby, but that doesn't make them the inventors of the panadapter, of radio waves or of s-meters.

I don't understand why Bill doubles down on his unfortunate statement.
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Bill -VA3WTB

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Were did I double down? I just said that you could be correct. It was Gerald that created SDR in ham radio. The radio's you mention had some sort of band scope as you call a panadpter.
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EA4GLI - 8P9EH - Salvador

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Were [sic] did I double down?
Here:



This is not adding anything to this thread. I am done, you can have the last word... go ahead.
(Edited)
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Bill -VA3WTB

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Salvador, I really don't know what your doing,,if you follow along you will see I said two times that you can be correct, and that I have been historically incorrect.

Gerald created SDR and I just rolled PSDR in with that and that may not be correct time wise.

As I said, the older radios had some kind of a band scope, if you wish to think of them as panadaptes that's ok.

Please follow along...
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Val DM1TX

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Hi Bill. I am completely with you on this page. I have this weird experience that I can here stations burried in noise band level distinctly when using the audio of my AirSpy HF+ then directly on my Yaesu FTdx 3000D. And the AirSpyHF+ is doing nothing else than getting the RX OUT from Yaesu. I hope I am not going nuts. And that for me was also a green light to go full SDR as in Flex Radio SDR.
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Andrew Thall

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I had a FTdx3000 before I upgraded to the 6300.  I hear many more digital stations with the Flex than I could with the Yaesu.  I couldn't be happier with the decision.  I'm sure that the upgrades available in the 6400 make it a VERY good choice.  My only complaint on the 6300 is that the internal fan is rather noisy when it kicks on -- I have bought a replacement fan but haven't had the need to open up the box and perform the swap.
Good luck!!
Andy, k2oo
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Andrew Thall

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I did not have them side by side.
Andy, k200
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Val DM1TX

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Side by side comparison was not a deal breaker for me. I will go Flex SDR nomatter what. Thanks for your feedback. Are you happy with 6300? Is is same arhitecture like 6500 is it? just 2 SCU instead of 4 if I am not wrong. How is it in contest mode?
I am asking because Iam also considering Preowned hardware from Flex and I see both 6300 and 6500 are still around. Thanks for your feedback.
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Bill -VA3WTB

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Both the 6500 and the 6300 have one SCU. So both antenna inputs work on one SCU.
The 6500 has roofing filters that makes it much better for contesting. The 6300 has none.
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Ken - NM9P, Elmer

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Technically not a roofing filter, which is a narrow filter designed to reduce in-band overload from adjacent signals.  The 6500 has a 3rd order bandpass filter for each band to reduce the possibility of overload from adjacent bands, which is better than the 6300's open front end.  The 6600 has 7th order bandpass filters on the contest bands and 3rd order filters on the WARC bands.

Ken - NM9P
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Val DM1TX

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Thanks Ken. Great info. However I am still googleing and try to find out what exactly is the difference in human language between roofing filters and 3rd order bandpass filters :-)  And yes, even now I do not realy need this I am keen to work contest if I have it.
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Dave Gipson

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I had no thoughts of contesting either...... until I got my 6600M..... Did I tell you I love my FLEX?
(Edited)
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Val DM1TX

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I very affraid the same will happen to me :-)
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sky

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Using the 4K desktop monitor is far, far more enjoyable than using the little 'M'  7 1/2" screen. You also have controls more conveniently acceptable in the SmartSDR window
(Edited)
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Neil D Friedman N3DF

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I don't agree, but these are not factors in choosing between the 6400 and the 6600.
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Ken - NM9P, Elmer

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In addition to what others have said about the difference between the 6400 and 6600:

With 2 SCU's you can have HF on one and use a transverter port on the other and do BOTH HF and VHF/UHF with a transverter at the same time!  

Also the 6600 has TWO transverter ports - This makes it very simple to connect two transverters and easily do full duplex satellite ops.  This can be done with the 6400, but is more involved, requiring additional switching, etc.

Although I am a middle level contester when I have time, I find that having 4 slices on my 6500 (precursor to the 6600) is VERY handy when doing digital modes - I can monitor multiple bands at the same time, even while tuning on CW or SSB with the third or 4th slice.

It is also VERY handy working splits - I can do full DX splits on two different bands at the same time.  The other day I was set up with splits for VP6D on 20 SSB and 17 CW at the same time using two panadapters and four slices.  Slick!  Try that on any other rig!  There may be others that can imitate it, but none that are as easy!

Ken - NM9P
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Dante - KM6VMR

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I think if you have the ability and luxury of installing multiple antennas, and I mean, good directional beam antennas at several feet above ground, it would be worth the extra cost of the 6600, otherwise, if you are in a HOA restricted neighborhood like I am, it may not make sense as you can have the best & greatest radio in the world, but if you r antenna $ucks, it may not make sense the extra expense IMHO.
(Edited)
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Tim W

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Val, I’m just a casual SSB operator and wanted a taste of Flexradio. I already have an Icom 7851 as a legacy appliance radio. The 6400 offered me a very economical entry into true SDR and prevented issues with spending too much. I figured that I could sell the 6400 and upgrade to the 6600 later if it was worth it. This was a good decision for me, and it may work for others too.....
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ua3lm

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Как качество ssb на 6400 и 7851 ??? передатчик.
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Val DM1TX

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Hello everybody, I was so surprised to see that a lot of people were answering to my question. This will just further consolidate my trust for Flex Radio Community and its dedicated users. Thank you all for taking from your precious time to answer. Trust in this Community made my decision easier :-) It is done! I am selling my 1.5 years old Yaesu FTdx-3000D. I have no complaints about it. Just a great rig! It is on eBay as we speak :-) I will take the leap of faith for the Flex Radio! I feel that the new radio will fit better with my lifestyle and available Ham time. I am also happy the the lack of knobs and switches would make my new Rig virtually Child Proof. We have two boys and you know how much they love pushing buttons :-) However I am still not decided which one of 6400 or 6600 would be. I have to be honest and say that huge price difference is what make me think this through. I see that Flex Radio is selling so called Certified Preowned equipment and looking also on a possible older 6500 (which I believe is the earlier version of 6600?) so 4 slices and 6600 performance on a better price. Another thing is to find out where the 6400 would be on the Sherwood Test list. I am thinking on a 6400 with Maestro or just a 6600. Prices are however much much higher here in Europe than in U.S. This is a show stopper for many of us here in Europe when buying U.S. made radio gear. I know in the end is just Business for the Owners of Flex Radio but if a price compromise would be made for the EU customers I am sure many many more would immediately jump in the Flex radio boat. Even if this could be done one time per year with a special price for HamRadio event at Friedrichshafen! Anybody at Flex Radio listening? And as Dante said here I have to point out that I have a small garden lot with limited options for big antennas. So I am just using a trapped dipole, a vertical and waiting the spring to put up the Cobweb antenna (from EAntenna). As I mentioned before I am 99% CW operator and I love the DX-ing. I think Flex Radio is now the natural option these days when propagation is not really helping. I see also that 6600 has an ATU included. No option to buy it without. I would still want to use my RF sensing MFJ-993B a great antenna tuner for my conditions. And then I simply do not understand why the ATU in 6600 is not better? I've read that the ATU from older 6500 is doing a much better job (this and the fact that it has 4 slices made me think of a preowned 6500 instead of a new 6600). Is it so difficult to implement an ATU as good as Elecraft has on its tiny KX3 on the Flex Radios? Most of us living in the cities have compromise antennas that need a good ATU. Is it the new 6400/6600 cooling fan noisy? How easy is to use the software and connect a Keyer to the laptop  and to work as you would sit near the radio itself? It is not a lot of recent information out there.  I would love to hear your comments further on. Whishing you all a great weekend! 73's from DM1TX  op. VAL
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Bill -VA3WTB

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The Sherwood List means little to nothing at all. None of the numbers posted there can be of any importance to the operator on any newer radio.

I don't know who is aying that the ant tuner in the 6600 is not a good one? It is as good as most others.

The fan in the 6600 and the 6400 make less noise then the 6500 because they run at slower speeds and are larger. You have to really listen to hear them.  I have a 6500 pre owned and it has been great. I do hear the fans but I also understand that it needs cooling. Small fans = noise of some degree.
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sky

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Bill: My 6600 fan is turning slowly but fast enough to make a light click..click..click noise like an old wind up clock.  (I checked inside and there is no obstruction to the blades.)
(Edited)
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Ted VE3TRQ

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Just as another data point, my 6600M fans are so quiet, I need to put my ear next to the radio to even hear them and know they are turning. Never run above 50W, so have no idea how loud it might be if pushed to the limit.
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WQ2H - Jim Poulette

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Fans? What fans?

73
JIm, WQ2H
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N5LB - Lionel B

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I use an outboard auto tuner because my antenna system impedance can vary widely; open wire / balun. Many, maybe all, rig tuners limit at 3:1 SWR match and I suspect even within that limit some R +/- jX values cannot be matched. 

Fan noise on my 6400 is minimal and is covered by ambient shack noise, especially the computer case fans.  The 6400 is seems much quieter than my 6300.

The Sherwood numbers are interesting but are the result of specific and standard test procedures and I doubt many of us ever encounter similar scenarios.  Maybe in a multi station/op contest but how many of us routinely operate in that environment? I don't think a few dB matter once you are in the F6K family. 
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Bill -VA3WTB

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Sky, if your fan is clicking you should contact Flex and tell them. They can send you a new fan so you can replace it your self .
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Val DM1TX

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I am obviously sorry that I have mentioned the Sherwood Test. For me are also some numbers that I do not see probably in real life. I notice however that Flex Radios tend to be on top of the list and that draw my attention. I am also a bit worried when a rig fans are too noisy. I am happy to notice that with new 6400/6600 is no longer the case. Thanks for clarifying that.
Is it complicated to rig a keyer then to the laptop and work CW from another room/country/planet :-)?