Are you getting the best receiver performance out of your FLEX-6000?

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In order to get the best receiver performance out of your radio, you have to optimize the signal to noise ratio (SNR) based on band conditions and the ambient noise that your receive antenna is picking up.  Optimizing the receiver SNR is a fairly straightforward thing to do and it is done by making sure you have the RF preamp set correctly and, this is the real important part, you have the AGC set properly.  Properly adjusting the AGC is done by using the AGC-T control, which is an often overlooked feature in SmartSDR, but the most powerful one for mitigating noise and optimizing the receiver SNR.

A detailed description of how the AGC in SmartSDR works and even more importantly, how to properly set it is covered in the updated HeldDesk article How does the Automatic Gain Control (AGC) work in SmartSDR.

I highly recommend taking a look at this article as a properly configured AGC can make the difference between getting that weak on in the log or not.
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Tim - W4TME, Customer Experience Manager

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Posted 3 months ago

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Neal - K3NC, Elmer

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Another great article from the Hardest Working Man in Customer Experience!! Thanks you wooly bear you!
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Tom Parish

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THANK YOU TIM! I am so grateful for this. I've had my Flex about 9 months and love it. But I admit I'm not up to speed on how best to adjust my 6400M for best receiver performance. This came at just the right time.
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Michael Walker, Employee

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That's my boy!  :)  This is awesome Tim.
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Bill -VA3WTB

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A very important article Tim. I always felt that the AGC-T is the least understood feature in SSDR.
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HCampbell WB4IVF

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Agree that the AGC-T control is a very useful Flex feature.  Hope that there will be follow-on improvements such as an option for automated AGC-T, or at least a visual display of the AGC-T setting.

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Santiago Mejia - HI8SMX

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Thanks Tim, as a new user (8 months) this article is invaluable.
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Wilbur Doolittle

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Is there a you tube on this?
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Neil D Friedman N3DF

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In FT8 mode, I set the AGC-T so that FT-8's green thermometer reads about 30 on a quiet band.  I set the AGC speed setting to "off."  Is this speed setting correct?
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Tim - W4TME, Customer Experience Manager

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Good question. The answer is "it depends".  Setting the AGC to OFF turns off the AGC algorithm altogether so you have to be careful about how you set the AGC-T so that you are not adding too much fixed gain to the recovered audio.  Using SLOW enables the AGC algorithm and can be beneficial to reduce the volume when there is external short-lived noise sources such as lightning crashes.
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Sergey, R5AU

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Neil, SDR provide high passband dynamic range and better do not use AGC at all with digital mods but utilize necessary filters for station selection. My AGC-T n Digi usually within 10-15 points without overloading receiver