6500 not as good as FTDX3000?

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I just purchased a 6500 and have been comparing it to my FTDX 3000 and to a SDRPlus SDR.  I am trying my best to like the 6500.  I love SDR but in a 3 way simultaneous operation I cannot get the 6500 to work as good as the Yaseu FTDX3000.  Maybe I am doing something wrong?

I am running the latest software.  All 3 units are tied to the same receive antenna via a powered HF splitter.  When using the FTDX3000 with its NR set to 4 the background noise falls to a comfortable level that makes listening to long rag chews very nice.  It is even better using the NR on a SDRPlay SDR.  Using the NR on the 6500 I cannot find a setting to get as clean or as much noise reduction without distorting the audio.  Also  when listening to  very weak signals the FTDX3000 with NR makes the station readable where nothing I tried on the 6500 would pull the station out.  This is very frustrating since I expected much more.

I researched all the reviews and played with the the FLEX at all of the hamfests.  I finally made the decision to purchase, but it has not been a great experience.

Am I doing something wrong?  Can anyone suggest any settings to try?  I do not want to return the unit since I do love SDR.


Demos KR4US
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Demos Doulou

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Posted 3 years ago

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Ria - N2RJ, Elmer

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The NR is a known weak point of the flex rig/software, or rather, it is a work in progresss. That doesn't mean overall one is better than the other. However if NR is make or break for you then the one with the better NR would win, but overall there are many criteria that people use to choose a rig.
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Jd Dupuy

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I never use NR to pull out a weak signal. I run the RF Gain up to quiet the background noise and increase the volume as needed. It's referred to as "Signal to Noise Ratio". Something I learned to perfection operating weak signal 144 thur 10 Ghz. Good luck!
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Demos Doulou

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Not just the NR, especially if it is still a work in progress, but the situation were the 6500 was not hearing as well as the FTDX3000.  That is the main issue.
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Hello Demos,  I hear you are using a powered antenna splitter.  Such units buffer the input to the radios and can introduce their own noise figure and reduce the dynamic range of the flex; which is much higher than the other radios in your test.  Try just switching the one antenna between each receiver and eliminate the active splitter.
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Jim Gilliam

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The noise reduction on the 1500, 3000, 5000 is nothing to write home about either. Also, that of the 6500 is about the same in my experience. I think the other rigs use chips dedicated to noise reduction. Perhaps it is much more difficult to write firmware to compete with these chips.

Jim, K6QE

Jim, K6QE

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Demos Doulou

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The best one I have found is implemented in SDR Console using the
Ephraim-Malah Noise Suppressor algorithm.  I use this on the SDR Play SDR.  This is implemented in software on the computer so it is possible.
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Al / NN4ZZ

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Hi Demos,
Here are 3 ideas that address the issue including the other good suggestions above.

Noise Reduction:

Peaking gain:

Automate the AGC-T setting

Check them out and add your votes and comments if you agree.

Regards, Al / NN4ZZ  
al (at) nn4zz (dot) com
SSDR / DAX / CAT/ 6700 -  V 1.10.8
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Demos Doulou

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Thanks. I will try these tonight
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I have only done side-by-side comparisons with my KX3 which I think has a great receiver in it. I think JD's technique above using RF Gain makes a huge difference. I discovered this during the weekly fox hunts where I could hear the hounds but the fox is buried in the noise.

I'll do all the normal stuff with AGC-T and a bit of NR and some APF (100 Hz and above only). Then I'll bring up the RF Gain to +10 or more even on 40 or 80 meters (where the winter hunts occur). Bang... the fox pops out of  his hole. It is generally the last thing I try but it often makes the most difference.

Because we are using our ears to do the comparison and not test equipment I would expect your results to be mostly even across the three receivers. I think the differences in most good receivers today are a bit beyond what our (my) hearing can discriminate. If the Flex is not performing as well in your ears and something isn't broken (antenna port, coax, front end, whatever) then I suspect adjusting some of the receiver's parameters will make the difference. Being able to test all three receivers side-by-side gives you the opportunity to really get an understanding of the adjustments.

For me, NR's weakness is not its inability to reduce noise. It seems to do a fine job of that. Where I have the problem is the distortion it adds to CW making it rather unpleasant to listen to. Reduce NR to a point where there's no distortion and NR pretty much isn't doing anything. Try that RF gain.

Kev K4VD
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Bob Kozlarek

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So it sounds like your comparison is mainly on the NR feature. Like ice cream, "noise" comes in many flavors. I had a noisy pole transformer several blocks away that the 6500's noise reduction virtually eliminated it, until I tracjked it down and had it replaced. I also had a dimmer in my home for which it did absolutely nothing. Comparisons with SDRuno on my SDRplay also showed that different radios respond to different noise quite differently. The only consistency, was inconsistency. The only definitely statement I can say is that it was better (more diverse) on my Flex 5000, but by no means is it "ineffective".
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hmmm.... I've had a 6700 and have been A/B testing it for months against the 3000's bigger brother the 5000.... and to date I've not found a single case where the 5000  received better than the 6700 - AND the inverse as well - where the 6700 received better than the 5000. I can manage in all cases to adjust them to match the ease of listening and weak signal capability of both radios. So I wonder if you're not doing something with the 6500.

One thing I find frustrating is that the NR and APF levels seem to always reset to 0. I am constantly having to go in and change them (this is using the Maestro). Likewise the TX and RX EQ's. Oh and the TX Delay for the relay out - always resets to 0. No matter how many times I've hit "SAVE" on the Global, TX, MIC profiles these NEVER get saved. My point is is it possible you haven't adjusted the level of the NR and/or NB? (and APF also does this if I remember correctly - resets to 0)



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I own both and overall find the Flex superior for my uses and operating style. I did however need to adjust my operating procedures when switching between radios. I was reminded of this a few weekends ago when I operated at a field event using a FT-450D.

When faced with a weak signal on the Yaesu or any mixer radio I crank down the passband or width depending on the features available. And often times need a bit of IF shift and audio conture to enhance the voice frequencies. The main problem with the 3k is the big gap between the 3khz roofing filter and the 500hz CW filter. Below 3k DSP is employed to narrow the passband which is a compromise.

As the Flex has an infinitely adjustable passband which is in the RF side of the RX not the audio chain like a mixer RX. I crank down the passband, adjust the AGC-T if needed and the RX audio EQ if needed. 

While I can get to a similar result with either radio, IMHO the Flex edges out the 3k while presenting an easier to use interface than a knob radio.  

I guess my message is this, try narrowing the bandwidth run a small amount of NR. Mine is normally set at less than 10 and also have your AGC-T setup properly. I normally run in the 35-40 range.

I almost forgot this, try the Binaural audio setting on the RX tab in the radio setup dialog. I use a set of powered computer speakers and I find the effect quite beneficial with speakers or headphone use. 

73, Jay N0IAI

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Manfred HB9FLU

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I own an 6300 with Maestro and a brand new FT DX 3000. Both radios have very good receivers, but when going on crowded bands, the filters of the flex are superior. I normally doesn't use the NR on both radios. For reducing noise I have a BHI noise reducting tool.

Reducing noise with the Flex is best done with the AGC-T.

73 de Manfred HB9FLU
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Which BHI noise reducting tool do you have?
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Manfred HB9FLU

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I have the desktop speaker and a module inside of my FT-817. The speaker sounds very good and noise cancellation is very effective.
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Just a couple thoughts
I also use the receive Equalizer to cut out any white noise and low rumbles that my Ears don't like and bring up what they like to hear because this is usually just garbage anyway, along with the AGC-T I very rarely use any NR.

If your using the S meter to say one radio receives better then the other remember the FLEX S meter doesn't change when a Pre-amp or Attenuater is used and MOST other radio's the S Meter change levels so you aren't really getting a true comparison because it is not calibrated. 

Signal to noise is by far much more important comparison from one radio to another and most Amateurs don't have the equipment to check this so we have to rely on our our ears and we all hear things differently. 

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Michael Aust

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I also suggest trying the Rx EQ, it makes a big difference for us old-timers with high end hearing loss !!
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Bill W2PKY

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Yes, dropping out the bass 3-500 Hz and below can help a lot.
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Gary L. Robinson

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I will attest to that also!
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Terry Tankersley

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My buddy sold his FTDX-3000 and bought a 6300 and never looked back.
Terry K7NY
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Bill -VA3WTB

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The one big thing the Flex has is that wonder called the AGC-T that no other radio has. You need to set the AGC-T at it's sweet spot. This is not a setting you set and forget it, you may need to change it slightly if conditions change, or changing bands. Once you have it set, it will make things very quiet and all the signals will be heard. Remember, every time you adjust the AGC-T wait a minute for it to calebrate. Keep moving it slowly and wait for it to kick in, then move again till you find the knee.
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Al / NN4ZZ

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Hi Bill,
IMHO, For many (maybe most or possibly even all) of the use cases it could be a "set it and forget it" option with the automation feature.   

Automate the AGC-T setting

And since you could still manually tweak it, you could figure out when you feel the automated feature is not perfect and still do it manually.   Currently it is easy to forget to constantly adjust the AGC-T with every band change, antenna change, condition change, or even which direction your gain antenna is pointed.  

Regards, Al / NN4ZZ  
al (at) nn4zz (dot) com
SSDR / DAX / CAT/ 6700 -  V 1.10.8
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I had a FTDX 3000 for a few years.. Purchased it the moment it came out.  I loved the unit.. I could not afford to keep both and was very attracted to the possibilities of the Flex thus picked up a 6300 and sold my FTDX (to my dad).  

There is no comparison to noise OR noise blanking... the FTDX is hands down superior..  I had them side by side for a while and noise that could not be blanked out by the Flex was gone with the FTDX... 

In general the FTDX has a more pleasant sound/audio out of the box.  However the Flex is far superior is every other way.  It just takes time to adjust the AGC, volume, etc. etc.  

Once you tweak the settings enough it starts to surpass the audio of the FTDX.  Couple that with all the functional capabilities you start to see the light.  I almost dumped the Flex because of this frustration but once i gave it time I learned to love it.  You will learn to love it once you have figured out the right combination of settings.

I would suggest to flex however to have pre-sets or suggested starting parameters that tune the radio right out of the box - even to the demise of performance.  Its discouraging when you turn it on and it seems no where near your ancient radios performance.
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Demos Doulou

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Thanks everyone for the comments and tips.  After spending many hours adjusting settings and doing comparisons, I decide that at this time the Flex is not for me.  I will take another look at the platform at next years Orlando Hamcation.

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Andrew Thall

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I had a FTdx3000.  My operation is strictly cw and digital.  The flex 6300 could decode digital signals that the FTdx3000 couldn't even hear.  I understand that the AGC-T takes some time to get used to.  Having said that, I would never consider going back to an analog radio.  I am anticipating that when SSDR 2.0 comes out (hopefully at Dayton), that operation of the Flex series will be even better.
Andy, k2oo