S-Meter Accuracy of FLex and Others - Rob Sherwood

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  • Updated 3 weeks ago
  • (Edited)

With all the recent (and not so recent) posts on the Flex
S-meter and its calibration, you might find Rob’s take on the subject interesting: 

  Rob Sherwood on “S-Meter Accuracy” 6-OCT-2016

While no Japanese rig has a properly tracking S meter, the following do:

  Flex 6000 series

 Apache ANAN

 Most K3 and K3S, though occasionally an individual radio cannot be calibrated properly. This includes the option to have the reading correct regardless of preamp or attenuator setting.

 Orion II once Ten-Tec updated software to allow S meter calibration. Orion II does not correct for preamp or attenuator selection.

 Eagle is good, except the S meter is microscopic and I think it quits at S9+30 dB. The Eagle reads correctly regardless of preamp or attenuator selection.

 Hilberling S meter is quite good.

 ADAT ADT-200A is very good but ergonomics in general are absurd.

 Elad DUO S meter is outstanding

 Perseus S meter is outstanding.

 With virtually all current products today having a virtual S meter, there is no technical reason the S meter cannot be programmed to read properly from S1 to S9+60 over.

When an S unit is only 2 to 3 dB, it makes QSB look much worse.*

Rob, NC0B

-------------

*Note (by DJ0IP): Most recent Japanese transceivers are using just 3 dB per S-Unit. This makes the received signal look stronger... but at the same time, the QRM, QRN, and QSB also look worse!

http://www.dj0ip.de/sherwood-forest/sherwood-sound-bytes/


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HCampbell WB4IVF

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Posted 1 month ago

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Jim Gilliam

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I am not sure that the Flex S-meter adheres to the accepted standard of an S-meter. I believe the accepted standard is that the S-meter should register the highest peak that exists with the bandwidth of the received signal. Roughly to me, it appears the Flex S-meter integrates all frequencies within the passband and provides a reading. I am not sure which method is better.


Jim, K6QE


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KY6LA - Howard, Elmer

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@Jim


Traditional S-Meters circuits were designed to INTEGRATE A 500HZ passband not peak

In fact NONE of the Japanese radios do either
(Edited)
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Jim Gilliam

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Is that 500 Hz. bandwidth of sampling for 0 to 500 Hz. or some where in between. It would seem if the latter were true, a person with a low voice response would register higher on the S-meter than one with a higher pitched voice.
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Paul

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Jim, you can select any 500Hz of RF bandwidth.  We all have more than that range within normal speech so the audio bandwidth of the baseband signal doesn't matter. (Unless of course we were to whistle a note that caused our signal to lie outside the selected 500Hz :)
(Edited)
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Bob - W7KWS -

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For me, the accuracy of an S-meter's calibration is useful for testing but is over rated and over used for communications purposes. To me, S-meter accuracy is of little value on any manufacturer's radio. Any relative indication of signal and noise strength is all one needs for letting the other station know if you can copy them.

The meter reading is more an indication of the path. The station is a factor but only a small part of the equation at best with propagation being, by far, the dominant factor.

It seems to me that absolute S-meter readings are used most often these days to feed the ego of the person on the opposite end of a QSO and does little to help the distant station make adjustments such as turning on the AMP or rotating the beam, Etc. So often I hear "you're rig is doing a great job. 30 over here", when it's the propagation that was contributing the most to the meter reading and QRP would have been entirely adequate. You've probably heard the old adage that I worked that station with a wet noodle. In other words, propagation was great and the main reason for the success of the contact. In reverse, the same "he-man" kilowatt station is received with an S-9 meter reading but a local noise source is also S-9 so the communications is marginal or non-existent. What did the S-meter reading tell the distant station in either of these two cases? In my estimation, nothing of real value.

For me, the real indication of signal value is the signal to noise ratio. In other words, the signal strength above the total noise strength in the receiver pass band. Any somewhat linear relative strength meter will give you these values, calibrated or not. This SNR, communicated to the the distant station, versus an S-meter reading, is a much better indication of your ability to copy the intelligence being transmitting. No egos involved!
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KF4HR

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Accurate or not, if there were no S-meters, what in the world would some of the guys on the night time 80M nets have to talk about?!  Just funnin'... 

I've always been under the impression that an S-unit was somewhere in the 5 or 6 db range, but it would make sense that some manufacturers might want to boost sales (and ego's), and use 2-3 db per S-unit. 
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Ria - N2RJ, Elmer

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Colonoscopies?
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Burt Fisher

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I'll make it simple when the receiver has a dummy load for an antenna I want it to read zero on my 6400M like on my KX3 and formally on my 7300.  Currently it read S7 on 80 meters on the 6400M and slightly lower on other bands.
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WA5GP

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Actually Howard I do have an IC 7600 and an IC 7610 and two other Icoms that I use regularly.  The 7610 has a better receiver than the 6400 in my opinion.  I use the 6400 daily on 75 Mtrs. I like the display and waterfall.  For digital and DX chasing the Icom wins hands down.  Easier to use in all modes and much more user friendly to setup and use digital.  I really love the fact that the USB ports on an Icom are actually usable,,, what a novel idea. Nuff of that!!! Like Burt said let 0 be 0... If a device Ie: Flex Radio doesn't read or represent a 0 reading with no signal present why waste the programming lines designing and displaying an S Meter that starts at 0  If bottom line reading with the lack of input is displayed at 5, why not just delete the first half of the Meter and let 5 be 0.  Oh wait that doesn't make sense either not even here in Texas.  I admit that I am new to the Flex concept and it is a learning curve.  No signal still should start at the bottom of a scale not some where in the middle.
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Bill -VA3WTB

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That is just it,,there is no such thing as no signal. I bet you guys never bothered going back to read Steve Hicks papers explaining this. This is simply SDR education.
I know what your thinking, that Steve does not know what he's talking about..lol,,,,too funny.
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Burt Fisher

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Steve Hicks is the measure of talented. In weather the public does not get a reading of absolute humidity, but rather relative humidity. As such it is almost 100% that those using a receiver with an S-meter want relative signal strength rather than absolute. In weather as one with deep knowledge of the science I prefer absolute humidity but as a ham I want zero to be zero. Maybe give us the option? 
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Ria - N2RJ, Elmer

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I did some investigation of my own on my 6700 and this is what I ended up with. All measurements are CW at 500Hz passband, no antenna connected.

160m - S2 - -114dBm
80m - S1 - -118dBm
40m - S1 - -119dBm
20m - S1 - -119dBm
17m - S1 - -119dBm
15m - S0 - -142dBm
12m - S1 - -119dBm
10m - S1 - -118dBm
6m - S0 - -143dBm

I do have to wonder why the 6400 reads so high? 

With that said I have no real complaints. I nearly never give real signal reports anyway, unless it's dBm. Far more objective. 
(Edited)
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Paul

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Hi Ria, nice to see you again. I repeated on my 6500 the same test as you. The results are similar. 

160m - S0 /-128dBm
80m - S1 / -121dBm
40m - S1 / -126dBm
30m - S1 / -126dBm
20m - S1 / -124dBm
17m - S1 / -120dBm
15m - S1 / -125dBm
12m - S1 / -125dBm
10m - S1 / -125dBm (but interesting S4 spikes every 1736 kHz with dummy load)
6m - S1 / -120dBm
4m - S1 / -120dBm

For comparison, the prevailing band-noise with the antenna connected was S3/ -110dBm on 160-30m and S2/ -112dBm on 20-4m. I'm happy with the results for the 6500. I'm not so sure I'd be content with some of the figures being mentioned for the new models. The quantisation noise does seem to be higher for some reason.
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James Kennedy-WU5E

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Flex good job on my FLEX 6600 S-Meter , it may seem strange I kept a log from 6500 to now on FLEX 6600 on S-meter reading I would change the normal 59 reading in AC LOG to the actual reading from the FLEX Smart SDR screen. One Ham said I'm only S-9+10 I'm running 1500 watts I discounted him as a rookie with deep pocket. well don't shoot me for that statement. hi hi . ... 
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KC2QMA_John

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The only way to make everyone happy is to have in the software a way to switch from a “True S-Meter” the way it is now on the flex or “Relative S-Meter” the way old radios S-Meters work.

I personally like the way the S-Meter works on the Flex Radios because it is truly accurate, S9= 50uV @50 ohms at the antenna connector if my memory is correct?

(Edited)
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KY6LA - Howard, Elmer

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I would label the Relative S Meter as the Bu** SH*$ meter
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Bob - W7KWS -

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I can hear it now! "You're S-9 plus 20 dB on my Flex. To understand what I'm telling you, go to www.flexradio.com and download the manual. Note that I've selected S-meter option 47. From this, use your scientific RPN calculater to determine what 20 over means with option 47. You'll still have a meaningless indication of what I'm hearing because I've not yet told you the band noise level at my station. GOOD LUCK".

73 & LOL!
(Edited)
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KC2QMA_John

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Lets call it the "Feel Good Meter"

It might make you feel good but it's still meaningless.

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Michael Coslo

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Wait... do y'all people actually look at the S-Meter?  I tell everyone I like that they are 20 over 9.  Then they like me!
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Jay / NO5J

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For accuracy I sometimes tell them they are 21.599 dB over 20. I suspect they don't really care for that much accuracy.

    #FlexRadio IRC chat

For real-time discussions

        SDRgadgets

User created documentation.
           Volunteer!!

         73, Jay - NO5J

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AA0KM

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There is always Atmospheric noise and local generated electrical noises  around and flexradio reports it.

Tuff to understand I guess.


I might add have fun and connect your ground to your center pin of the pl-259 and out
to the ground rod.

You will be amazed at the local noise. This being I live in the city. YMMV.

(Edited)
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Paul

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Clearly the number of microvolts at the antenna connector is due to many factors which are outside the control of both the stations in the link. I suggest that regardless of how the meter is reading is derived, it is of little value.

IMHO, a plain language radio report is much more use. These are still used widely outside amateur radio, I paricularly like the example on page 6.12 of this CCEB document:

http://www.k1chr.org/ACP%20125%20%28G...

Particularly the statement in section 631 which says; "A station is understood to have good signal strength and readability unless otherwise notified." Maybe we could all adopt this approach. But then what would we find to spend our time debating? Over & Out ;)
(Edited)
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WQ2H - Jim Poulette

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Maybe we could debate "over & out" being a paradoxical phrase that John Wayne would have used in the movies - but is something that would never be used in real ACP-125 tactical procedures.

Sorry Paul - couldn't resist. :-)
(Edited)
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Paul

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Great planJim. If we ever meet on the air I promise to start that debate with you! :-D
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WQ2H - Jim Poulette

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Roger out.
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Ross - K9COX

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I used to repair CB radios in the late 60's. I would change the screen drop resistor on the final and on occasion the cathode resistor. Also would adjust the S meter for lots of deflection...I was a hero
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Ken - NM9P, Elmer

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Most of the time when I hear a station giving reports like "You are S9+30" when I only hear them at S8, I can be sure that they are using about 30 dB of preamp on a rig that doesn't compensate its S-Meter.  Especially since I only run 100 Watts!

Back in my "CB Days" (1972-74) I used to watch guys turn on their external preamp and exclaim "Look at how much more powerful this makes my radio!  It brought my noise up from S3 to S7!  Now I can hear everything!"  Then they would complain about their darned neighbor down the road who was splattering 15 channels wide.  They never understood that they were their own worst enemy by running a preamp that overpowered their receiver.  But then again, sometimes that neighbor was driving a sweep tube amp well beyond saturation with an AM signal and really WAS 15 channels wide!
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Stan - VA7NF

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I like to just lean back and enjoy these conversations, particularly s-meter ones.  Let's see:
 - The Flex S-Meter accurately measures the voltage at the antenna connection but the various authors don't like the accuracy, they want the old inaccuracy.  It also ignores antenna gain and external pre-amps.
 - The dx/contest station cannot be clearly heard but still 5-9 or 5-9-9.  I'm a contester and guilty as charged.  The log needs a number and convention is fill it with a default, even N1MM pre-fills with 599. 
 - And now: "Connect to a dummy load and there is still noise."

On that last one, consider the radio chassis is the other half of the antenna connection (unbalanced input connection).  That chassis is at the junction of two antennae, one the safety ground out to your power panel and ground, and the other your RF ground wire and/or any coax connected.  The centre wire may be on the dummy load but the ground has many signals; then add in the front end generated noise.
An aside: While we are at it, lets tell those electrons to stop jumping out of orbit due to thermal activity or nearby static charges and also demand they do not create EM waves. This is obviously the fault of the Flex management and programmers not an act of nature and the basis of our hobby.

Tongue-in-cheek but also factual (subject to future posts)
Stan VA7NF
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KC2QMA_John

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Since we are commenting on S-Meter here is my only complaint and it’s a tiny one.

It would be nice if you could select in the software to go from the current gradient color scheme of the S-Meter to switch to Solid green up to S-9 and from S-9 to +40 solid Red. Would also like a longer peak hold.

Not really that important but I just think it would be slightly easier to read.

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Thomas NE7X

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There is really two different schools of thought here:

1) Technical engineer who wants a precision lab instrument S-Meter
2) General Ham who just want to know what the S-Meter reading of a signal is above the internal nose of the radio with no antenna connected

Both are correct and have valid points..

This is why a good compromise for both would be if Flex would add a menu switch to allow both users to have the S-meter of their choice.


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KY6LA - Howard, Elmer

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Wrong

https://en.wikipedia.org/wiki/S_meter

A S0 Reading Implies -127dBm NOT ZERO.

At -273degrees C Zero would be -143dBm or MINUS S2.5 NOT ZERO

I see no value whatsoever in a relative to no reference whatsoever strength meter.

its absolutely meaningless except to give false comfort to those who do not understand that what they are seeing is absolutely useless...

(Edited)
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Ria - N2RJ, Elmer

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“if I short the inputs to any other type meter it reads zero. A digital VOM does not have a reading above zero even though active circuits inside it may have electrons flying around inside. Zero ought to be zero.“

Actually, it doesn’t. Nearly every VOM I’ve used measures the resistance of the test leads in addition to the resistance of the load under test. Usually you see something like 0.05 of an ohm or similar when you short the leads of a VOM. It’s true for most every meter, from a high end fluke to a free harbor freight one.
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Craig Williams

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All mine except my Waveteck DM27XT. Actually reads 0.0 with the test leads shorted. And, it's probably a Beckman as Waveteck bought Beckman from Emerson Electric after I left their Doric Scientific Division around 1988. Now no Beckman or Waveteck.
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Burt Fisher

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Ria this is not the forum discuss an opinion on contests. If you are trying to bait me, I will pass. My comment on zero being zero need not be rehashed. Beta was technically superior to VHS but the market went to VHS. Thus the S-meter purity issue may be won by Flex but the market will determine whether my opinion has any merit.  The talent expressed in this thread humbles me as I cannot hold a candle to the science demonstrated here. 
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Ria - N2RJ, Elmer

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Except that zero is not zero as has been repeatedly explained.

I support flex in having an accurate S meter rather than a feel good one. As an owner for the past few years, three time award winner and former alpha team member and being friends with the senior staff in the company I fully understand and support their reasoning. 100%.
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Gerald - K5SDR, Employee

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Burt,

I hear your desire to have the S-meter read zero but to do so would render the S-meter to be totally worthless for any purpose other than to watch it squiggle.  An accurate S-meter actually serves a useful purpose for properly setting the preamp gain or attenuation for best dynamic range of the receiver given the antenna and operating conditions.  I described this in another thread.  Therefore; we have no intention of changing the S-meter to render it useless.  An accurate S-meter also gives you a true RMS power measurement of the received signal at your antenna port, which may a novel idea in ham radio.

Thanks for your comments but this subject is now respectfully closed.

73,
Gerald
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Bob - W7KWS -

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The S-meter formula that Howard refers to has been an accepted standard for S-meters for as long as I can remember. Probably from when I was first licensed in 1957. How has this agreed-upon standard become so convoluted?

When I make a contact, I 'd like to know my TRUE signal report, not some arbitrary strength report made up by feel good radio manufacturers. The only way to get the accurate information is by everyone following the same standard, even if it isn't your favorite.

Kenwood, Icom, Yaesu and many of the other manufacturers are all different when receiving the same signal. How am I to know my true strength if my report is from any of those manufacturer's radios? The only way is by using a standard. It's such a shame that so many don't. What a mess it would be if we used arbitrary dits and dahs to communicate instead of Mr. Morse's standard.

If the standard is to be changed, fine but it has to be done via agreement of a majority of those effected, not by a few manufacturers that have decided they have a way to fool folks into buying more of their equipment. If this forum is representative, the majority here are with Flex and the existing standard and not with the others.

It's clear that a meter showing S0 with no signal is ignoring the total noise strength in the receiver pass band which is important information if you are really a true radio person. Ignoring this is poor practice at best?

In the mean time, if we happen to meet up on the air, please report my signal strength by using the current standard, whatever that is at the time. This way I can avoid being confused over what you're trying to say. Currently, Flex is one of several radios that make that easy for you. All you have to do is look at their S-meter and report what it says. I assume most of you reading this are here because you own a Flex. Reports from other radios that aren't standardized will likely be very confusing as they usually don't agree with each other let alone reality.

While you're at it, the Flex is also giving you a fairly accurate noise strength reading on the S-meter. If you pass this along as well, I'll know my signal to noise ratio and will have a pretty good idea of any need to use phonetics, repeats or anything else that might help to get my message across to you.

As Elvis would have said, Tha=×#$@&%$= (Oh yea, I forgot, STANDARDS) Thank you, thank you very much!

73!
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Bill -VA3WTB

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Bob, more to your comment.
Setting the standard aside, we can look into the way the signal is reported.
On an non SDR radio the signal voltage is sent from the AGC path. In this there are problems. Depending on AGC settings and the circuit design the meter can be a long ways off. And when you consider filters, preamps, all effecting what it reads.

A Flex radio is very simple. It takes the signal off the antenna connector and converts the signal to voltage, 50uv = S9 @50 ohms. Note, there is nothing in the radio influencing the signal report.

As I mention above, the receiver is sampling the bins in the receiver, the problem is there is always energy in the bins, always. some people wrongly think that with out an antenna connected there should be no energy in the receiver bins.

Have you noticed that by widening the band pass filter more bins are called on and the S meter reports this? The signal goes up. However as Steve explains the energy in the bins comes from many places within the radio itself. Even the connector itself sticking out the back acts as an antenna and can pick up noise outside the radio. In a direct sampling receiver even a dummy load can be an antenna. the smallest amount of energy outside the radio can be heard in the receiver. This energy would never be heard with other types of receivers, so, the Meter would never report it.

That is why many radios report 0 without an antenna, they simply can not hear the energy and they don't have receiver bins at all.

This is all part of direct sampling technology love it or hate it.
Flex spends a lot of time and energy to make the Flex Radio as lab accurate as possible. I can't see them making changes so the S meter that would report random non effective readings simply because older or non SDR radios do.

It is hard to believe so much has been writen on this, because really? who cares. Every station is reported to be S9+ anyway.

The only value in this discussion for me, is the fascienation in the understanding how our cutting ege Flexes work.
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Burt Fisher

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Bob, W7KWS, does everyone you talk to use the same exact antenna mounted at the same height in an open field with the exact same ground conductivity? If not the purist S-meter means nothing.
Lacking that  you are not getting a TRUE signal report, you are getting an arbitrary strength report. 
(Edited)
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Ken - NM9P, Elmer

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Burt, that makes no difference. Because my S-Meter reads the signal strength at MY antenna system. What others use, and the signal levels at THEIR antennas are irrelevant.

In the same way, I could say that the other operator’s signal report is meaningless because I COULD be using a five over five and/or a 1500 Watt amp instead of 100 Watts and a low log periodic.

In either case, if everyone uses an accurate, calibrated signal strength meter, we can exchange information that reflects conditions at both ends of the exchange....except for contests and DXing, in which case it is all irrelevant. But the S meter is still helpful to aid antenna bearing adjustments.

In any case, this whole discussion, while interesting, is academic, because I think it very unlikely that FRS is going to change their commitment to lab quality measurements in their rigs.
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Bob - W7KWS -

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Hi Burt, There hasn't been a standard established for antennas, but there is a standard for S-meters. By following this standard you can do me the favor of accurately telling me what your ability is to understand my message. It isn't meant to be for you.
(Edited)
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Burt Fisher

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If everyone uses an accurate, calibrated antenna in identical physical locations, we can exchange information that reflects conditions at both ends of the exchange.  Bob if your message isn't meant for me no need to respond.
(Edited)
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Ross - K9COX

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Contesters don't need no stinking S meter, everyone is 59...
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Barry Simpson

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I must admit that I, like Burt , would very much like the S Meter to read zero when there is zero signal, ie a dummy load. That is what the K3 does. When I first got my 6600M I found the S Meter readings to be very disconcerting, especially when I discovered that the higher that I turned up the pre-amp, the lower the S Meter reading becomes.

Based on the explanations on this forum, I understand that the minimum S Meter reading is not measuring the minimum signal level but the receiver MDS level. Therefore the experience of the S Meter going down whilst the pre-amp settings go up is logical. However I would much prefer the Elecraft implementation which does measure signal levels such that , for example, on 80m into a dummy load, it reads zero. With an antenna connected it reads S4 being the ambient noise level and signals above S4 register their true S reading. None of the K3 S Meter readings is affected by turning on the attenuator or the pre-amps.

Therefore what Elecraft have done surely can be emulated by Flex as it is a software issue.

That’s my take on the S Meter debate.

Barry Simpson VK2BJ
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Bill -VA3WTB

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They need to emulate Flex..Lol
The K3 is not a direct sampling receiver.
(Edited)
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Bob - W7KWS -

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Hi Bill, you don't need a direct sampling receiver to follow the standard. Most IF type receivers have taken the easy way out and measure the AGC voltage instead of the actual passband power which is more involved.

In the AGC approach, if the power in the pass band is below the AGC knee you get no voltage thus the zero reading, even if there is a signal present. Unfortunately, this is a totally misleading result.
(Edited)
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Bill -VA3WTB

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Because the K3 does not have direct sampling the receivers are very different in how they work is my point. When you take voltage from an AGC circuit it is not accurate, It is not the same as taking it from the antenna port by passing anything that could effect the reading witch is how direct sampling works. A direct sampling radio enjoys many advantages, this is one of them.
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Bob - W7KWS -

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Hi Barry, I just wish all manufacturers would follow a standard so we know what it means on the far end of a contact.

If the current standard needs an update, so be it, but as it is is now, there is no way for me to know what 569 means if you give that report since few radios are calibrated the same.

It seems to me that we should either use the standard that exists or reach a consensus on a new one.
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Paul

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Bob, instead of a new standard I vote that we revert to a well established and subsequently revised standard; plain language radio reports. Eg. pg 6-12 here:

http://www.k1chr.org/ACP%20125%20%28G...
as highlighted earlier in this thread.
(Edited)
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KY6LA - Howard, Elmer

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Rob Sherwood on “S-Meter Accuracy”   6-OCT-2016

While no Japanese rig has a properly tracking S meter, the following do:


 Flex 6000 series
 Apache ANAN

 Most K3 and K3S, though occasionally an individual radio cannot be calibrated properly.  This includes the option to have the reading correct regardless of preamp or attenuator setting .

 Orion II once Ten Tec updated software to allow S meter calibration

       Orion II does not correct for preamp or attenuator selection.
-
. Eagle is good, except the S meter is microscopic and I think it quits at S9+30 dB.  The Eagle reads correctly regardless of preamp or attenuator selection.


 Hilberling S meter is quite good.


 ADAT ADT 200A is very good but ergonomics in general are absurd.


 Elad DUO S meter is outstanding


 Perseus S meter is outstanding.


With virtually all current products today having a virtual S meter, there is no
technical reason the S meter cannot be programmed to read properly from
S1 to S9+60 over.


When an S unit is only 2 to 3 dB, it makes QSB look much worse.* 
Rob, NC0B
-------------
*Note (by DJ0IP): Most recent Japanese transceivers are using just 3 dB per
S-Unit.  This makes the received signal look stronger... but at the same time,
the QRM, QRN, and QSB also look worse!

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KY6LA - Howard, Elmer

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For test purposes, I shorted the antenna on my Elad FM-DUO.

The S-Meter Reads CORRECTLY... S2 (NOT S0) on 20Meters

It's truly unfortunate that the Japanese continue to stick to the totally inaccurate AGC Voltage Circuit to FOOL PEOPLE into thinking that they have a real S-Meter.   As a result, Joe Ham has been SCAMMED into believing that by shorting his antenna he should see S0 when in fact nothing could be further from the truth.


As Rob Sherwood says, none of the Japanese Radios are accurate and they have done a serious disservice to the ham community by promoting ignorance of technology.


I guess I am personally upset when I see people actually wishing to revert to a ridiculously and totally incorrect and inaccurate mode of measurement when they already have a totally accurate lab grade instrument.

When I see this sort of desire, I am reminded of the movie "Idiocracy"

Coming from a school teacher like Burt, it makes you wonder if our children will be doomed to ignorance.
(Edited)
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Burt Fisher

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Insulting me I thought was frowned upon here? ("Coming from a school teacher like Burt, it makes you wonder if our children will be doomed to ignorance.")("When I see this sort of desire, I am reminded of the movie "Idiocracy"). 
I saw this on the first page, "And remember when using the Community always show respect to others regardless of their opinions. Give people the benefit of the doubt, just like you would if talking to them in person. Posts that include personal attacks..."
(Edited)
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Bill -VA3WTB

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That is true Burt,,we need to always respect others opinions....
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KY6LA - Howard, Elmer

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@Burt. No insult intended.
‘My quoting that brilliant movie “Idiocracy ‘ which I believe everyone should see because it will make them think of a dystopian future where people prefer measurements that feel good rather than ones based on a scientific fact.

Yes I worry about our children when educators like yourself would prefer to teach them things that feel good rather than basic science. As a scientist and engineer it obviously upsets me that people would deliberately choose a meaningless irrelevant measure over scientific fact especially when most will even admit that they know their measure is useless but it feels good.

I must admit that you usually do not get under my skin with your regular outlandish opinions, but promoting ignorance over fact especially after it has been explained to you in great detail where you are factually wrong is just plain hard to take.

Finally you are spouting nonsense about comparing apples to potatoes with the attempt to measure two sites with so called calibrated antennas Even you know that there are far too many variables in a propagation path like difference in near field obstructions and local terrain which caus real world asymetry for such to be possible.
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KY6LA - Howard, Elmer

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@Bill

I always respect others OPINIONS

But there is a big difference between OPINIONS and SCIENTIFIC FACTS.

I do not respect deliberate promotion of ignorance of scientific acts.
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Burt Fisher

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You did not say regular outlandish opinions are not appreciated, you did say, " your regular outlandish opinions", when you add your it becomes a personal insult. It is possible I feel the same about your opinions but I don't feel the need to be personally insulting. In your second paragraph you used the word "people" which is not personally insulting. However when you said, "you are spouting nonsense ", that was a personal insult. 

My opinion is that the S-meter is not like a voltmeter, ammeter or an ohmmeter, it reads facts. An S-meter is a relative meter subject to almost infinite variables. Thus trying to assign a constant to an S-meter is like trying to heard cats. What I did not say is any other opinion is outlandish, ignorant, nonsense even if I were to believe so, as that would be unnecessarily insulting. 
When you said, "@Burt. No insult intended. " I will not comment. I am trying to follow the Flex Community guidelines.
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Paul

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Here-here Burt & Bill. IMHO, all the more unfortunate when the transgressor is an Elmer.

Howard; to me, your posts are usually interesting & enlightened. This is merely a hobby, it's a shame you appear so passionate that you let this topic irritate you.

Paul; "OUT" ;-D
(Edited)
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Michael Coslo

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I'm not certain what to say, Burt.

The levels that correspond to "S" are measured at the antenna input on the receiver, and not related to the antenna.

Your example is based on measuring  the strength of the transmitter, not the device you are measuring the transmitter with. Of course you want a specific antenna.

I offered a solution that would allow you to have a S-Meter reading that you want. Others can have a meter that reflects exactly what they want, in fact they could possibly even choose between 3 db per S-Unit and the standard 6 db per S-unit. 
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Geoff AB6BT

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Correct. 

"field strength means the magnitude of a vector-valued field (e.g., in volts per meter, V/m, for an electric field E)."

So without knowing the length of the antenna used the field strength measurement would be  meaningless.

S unit measurements are not field strength measurements.
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Bob - W7KWS -

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Hello once again Burt!

Again, your comparison of a broadcast quality field strength meter and a S-meter appears to be comparing apples to oranges. The two are used for somewhat different purposes.

Your thoughts imply to me that you embrace the FCC rules (standards) describing the Amateur Radio Service and standards set for broadcast quality field strength meters.

https://en.m.wikipedia.org/wiki/Field...

If my understanding is correct, I suppose this comes from your career as a broadcast chief engineer.

What is a mystery to me is why you accept some standards and not anothers. To me, your many posts only express "what YOU want" but have completely missed the mark in showing anyone of us why we should want it or why it's a good idea.
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Paul

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Hi Geoff, the E field strength is inversely proportional to the distance (d) between two bodies at different potentials. The distance in a radio context is the distance between the tx and rx, not the length of the antenna.
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Paul

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Burt, I guess you're alluding to references to amateur radio being a 'service'. Two things come to mind;

AFAIK the FCC regulations apply only in the US. There is a whole world outside their juristiction. FYI, the UK regulatory body (OFCOM) describes amateur radio as " a hobby and a service".

I am on the air a reasonable amount. In paralell with that I also run a WebSDR. I consider the former to be one of my hobbies - for which I hold my licence. However, the latter is a service which I provide free of charge, independently of my licence.

I am well aware of that some amateurs do provide a service (RAYNET, ARES, etc) but my experience is that they are actually in the minority. IMHO, listening or being on the air (like the majority of us) does not provide a service, however important we might think it to be.
(Edited)
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Gerald - K5SDR, Employee

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Please read my post https://community.flexradio.com/flexradio/topics/6600-noise-levels-10db-higher-on-my-new-6600-vs-my-older-6500 to understand how to use a properly calibrated dBm S meter to properly set radio gain.  I know for an absolute fact that Sherwood agrees with me on this.  He and I have discussed many times.  Let me just for the record state that we have no plans to change it to an inaccurate S meter. 

Here is the correct calibration taken from the Wikipedia S Meter page:


And here is typical atmospheric noise in 500 Hz depending on location:


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Michael Coslo

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Of course the opinions are different on the QRZ forum. How many of those folks even own a Flex? The internet is full of Ford versus Chevy trolls, and if a person doesn't like Flex Radios, that accurate S-Meter on their rigs is a real deal breaker, and for a radio they'll ever own because they chose to like a different one. Make no mistake, if every S-Meter out there was accurate, but Flex had an inaccurate one, they'd still be deriding it

I want an accurate, reality based signal strength meter. The concept of arguing for an inaccurate one is pretty amusing. But entertaining, and no doubt.
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Bill -VA3WTB

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I hear a remark a lot here with the word purity. It is NOT about purity. Flex just simply pride them selves for making presission radios, not for purity but rather a business decission. But while using the techology that Flex uses in their radio, presission is a byproduct of such a platform. It would take a fare amount of effort and programing to build old technology type performance into the Flex radio.

As Gerald stated they are not inclined to dumb down the S meter to reflect older technology.

It seems that this discussion has run it's cource, and it is not up to me to decide that, but for me I have little more I can add. It has been interesting.
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Burt Fisher

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Michael yes many on QRZ forums are not Flex customers but does that invalidate their opinion? Isn't that where new customers are coming from? I have a KX3 whose S-meter reads zero on 80 meters, a good American company with great customer service like Flex. Are they doing it wrong? I have an anemometer it's measurements are interesting to me but my house is surrounded by trees thus not meeting a standard, just like hams that live in various environments invalidating the most carefully calibrated S-meter. My anemometer does not read 10MPH   in a calm to account for its protected situation. 
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KY6LA - Howard, Elmer

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@Burt

I have a Barometer at my house that reads 760Mm Hg. It’s just as ridiculous that it should read zero as the failure of the KX3 to follow accepted standards.

Time we closed this ridiculous topic
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Bob - W7KWS -

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If your description of the KX3 is accurate, it means the KX3 doesn't conform to good engineering practice. Either that or it's a defective radio in light of the K3 which is reported by Rob Sherwood, via Howard's post above, to follow the established S-meter standard.

How could it be good practice for Elecraft to embrace two different calibrations in the same product line? If they have, it doesn't say much for using either as an example for establishing a convincing argument.
(Edited)
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Ted, NX6C

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Burt,
   It seems that your desire to increase the sales of FlexRadios is a good thing.  No disrespect intended with my idea for a signal strength indicator.   I learned about tuning a radio for maximum speaker output and signal clarity by using this 'magic eye'.
   I know this places me as an old-timer.  My Dad built our own radio/phonograph system and later we had a TV chassis propped up on our mantle piece.  He built electronics that filled the house and the garage workbench.  I am completely interested in the technology myself.  

But it was the magic of the magic eye that intrigued me as a young boy.


To many hams a relative indicator is all they need.  They are used to it and they can utilize it to peak the tuning of a signal, just like the magic eye above.  ( I hope the image is moving like the original)!

   Along the way we've all learned, here on the FlexRadio forum, that we finally have in our ham stations a calibrated power-meter that has it's input at the antenna jack.  
   
  I applaud flexRadio for advancing the state of the art in my ham station.  

Anyway,
  My wife says to make a point and don't keep writing.

I'll listen to her here.

I also think this discussion has run it's course.

I do appreciate the thread and especially the links to the 
Wikipedia S-meter articles.  Reading them again is useful.

Ted Spiegel
NX6C

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HCampbell WB4IVF

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No horse is too dead to beat.  (-:



Howard

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