S meter

Burch - K4QXX

What I don't understand is why people care what their S meter says when there isn't an antenna connected to the radio.  If it's S0 or S4 without an antenna connected to the radio, who cares!  A radio without and antenna connected to it is useless.  I'd much rather have a S meter that is accurate than one that reads S0 without an antenna connected to the radio.  I have never used a radio without an antenna connected to it....

KL4QG

It’s accurate just asking question Is this computer ok use with Flex 6400M my brother gave me today

KL4QG

CW S-2.8-3 in 20 meters and SSB S-4 Not sure how zoom in screen yet or what + or _ Does on picture at bottom far right

Stan VA7NF

Interesting how certain people always line up behind this S meter topic, and they always talk about the reading of NOISE levels.  The discussion never goes to how to measure ONE signal, much stronger than the noise, within the pass-band.  Narrow or wide it always reads the same.The wider the pass-band the more (number of) individual noise pulses are received. 
Homework: Go to WWV, narrow the filter to minimum and measure the strength of every sideband element.  Then widen the filter to cover the entire modulation and measure again.  The sum of every sideband and carrier will equal the full signal received. 
In the same way a single panadapter bin (width / 4096 bins per display) can vary from 3418 Hz per bin at 14Mhz to 0.25 Hz per bin at 1Khz.  More signal (noise + real signals) per bin will come in at a wide panadapter setting than at narrow.  Actually you should expect to see, with just background noise, a 41db (7 true S units) difference in the panadapter noise level on the dbm scale with some signals peaking above that noise level.  Zoom in and the noise per bin will drop but the individual signals will remain the same level.
 

Michael N3LI

Should be Fine Joe. You actually don't need a lot of horsepower to run a Flex Sig series since most of the processing is done inside the radio.

Michael N3LI

It's a strange conundrum. The Flex is showing it much more accurately, but so many people are used to the terribly innacurate readings legacy radios have, and it seems like the Flex is wrong, when it is the radio doing things correctly. Takes some getting used to.

Burt Fisher

Flex doesn't care what you want related to the S-meter, they have an ideal theoretical plan that is different from most others. Most people who buy ham radio equipment are not Einstein's and just want what you want, for zero to be zero, not 7. In the end customers will vote with their feet. Of course if you wanted a lab instrument instead of a ham radio transceiver, you came to the right place. Some Flex fans are so hateful of other companies they will call other S-meter readings meaningless nonsense.

KL4QG

Lovin’ my Flex 6400M

KL4QG

Yes. I’m used to it now no problems

Dave WB7WHG

Thanks for your comment, Duane! Good information, as always

Michael N3LI

The problem with S-Meters. An S-Meter on a legacy radio is based on an AGC tap, and while calibrated to give S9 for -73 dBm. But other than that, aren't accurate.

http://www.seed-solutions.com/gregordy/Amateur%20Radio/Experimentation/SMeterBlues.htm

Which one is right, Burt? All of these radios tested out differently, and not consistent within themselves.  Which one do you think FLex should imitate?  I'll vote for something accurate, not an AGC tap. 

I am amazed that some are arguing for purposeful and deliberate inaccuracy. The Flex measure of dBm to S-Units is a release from a bad system. 

Burt Fisher

My opinion is of little importance  The market will vote with its feet and will decide do they want an S-meter that meets a theoretical ideal or do they want an S-meter that reads zero with a dummy load attached. Judgement day is coming with the introduction of the K4. Flex and Elecraft, both companies with quality and customer service that have no equal. It's up to the market who gets the edge.

KL4QG

I agree my vote S meter reads Zero with dummy load attached

Steve K9ZW

This has been discussed at length before.  

In the traditional approximations vs closer to theoretical measurement, FRS has been consistent with their philosophy of using the available technology of their platform by adopting the closer to theoretical approach.

The former compromises over time became a "availability heuristic" (basically a rule of thumb based on availability and experience, rather than correctness) but as we know were never truly accurate nor perhaps even appropriate if we're after true signal strength.  

The FRS approach plays closer to theory, and yes that includes faithfully observing the noise from empty ports.  This is more accurate than our generally accepted rule of thumb approach that an open port is silent by ignoring the observable noise.  

The contrived S-meter scale many of our favorite receivers from the past are amateur radio market engineered-marketing that everyone knew was "feel good" rather than factual.  

We exacerbate the S-meter scale nonsense by tradition, especially the everyone is "59" or "5NN" when contesting or in a hurry.

Is the FRS implementation lab grade perfection?  Will it toe up and hold the line with your professional grade station monitor?  Depends, though you can know it will be closer to lab grade than the approximations of legacy radios.

In prior discussions community members suggested implementing an alternative scale making SmartSDR report to them S-numbers they are happy with, rather than accurate.  FRS didn't take up the suggestion.  Truly what manufacturer would willingly "fake it" when they have the real goods because yesterday's market products were actually wrong?

So yes your Flex-6000 is going to tell you about the noise it actually hears, rather than ignoring that noise.  

On one of my older cars with a KM only speedometer is a KPH to MPH conversion chart - so you know that 55 MPH is 88 KPH and so on.  If your ham radio enjoyment depends on having a vintage pseudo-S-meter you could make yourself a similar chart.

73

Steve
K9ZW

Blog: http://k9zw.wordpress.com  

 

[Deleted User]

I have my deposit in for my K4 . . . Can't wait

KL4QG

I have no problem with S meter showing true noise and stations transmitted signal strength I’m starting understand my Ten Tec Omni 7 plus shows true noise in signal strength both my 6400M and Omni 7 Great on receive and transmit. I just don’t use Omni 7 after I got Flex 6400M it’s almost like 6400M put a Witches Spell on me **** -it’s addictive like candy pop corn .

KL4QG

Cool is K4 about same price as 6400M

Ted VE3TRQ

Yup, but it won’t be available until next year, and it has a 7 inch screen. How good will the software on a PC be instead of using that screen (even if it can be displayed on an external monitor?) I’m not slagging Elecraft equipment, I have a K3 and a KX3 - just it seems more an answer to the Icom 7610 than a Flex 6400M. (I _love_ CoolAid :-)

KL4QG

CoolAid **** time will tell

Bill -VA3WTB

Ted, the Flex 6400M and the 6600M are mostly in their own leage. With connectivity, Remote, and there just is no other stand alone radio with such a great panadapter,,nothing. And simple to use.

I agree it will be very hard for Icom, Kenwood, Yeaesu, to keep up with the K4.

KL4QG

I’m going ask a curse word lol how about Apache labs Anan SDR do they make anything like 6600M or 6400M

Bill -VA3WTB

Anan has no radios like the 6400M or 6600M.

Ted VE3TRQ

From all reports, Apache Labs makes a fine transceiver, but I have also heard it’s a bit more like driving a Lamborghini :-) Have a contract with the mechanic, or be one - they are much more hands-on as far as configuration goes. But they really do perform, apparently.

W5UC

Joe, if you haven't already, try turning the Preamp "RF gain" in the Ant tab to the "On" position. See if your noise floor doesn't drop.


73,
W5UC

KL4QG

Yes it. Dropped all good thAnks

Burt Fisher

How much noise does it "actually hear" when a dummy load is attached right at the connector with no lead?
I get S4 reading with a resistor connected right at the coaxial connector.

KL4QG

S3-4

KY6LA_Howard

Which means that at the frequency you’re listening to Your radio is only capable of hearing only is -127 dMm plus 3x6dBm or -109dBm