Why do sdr's lack?

Answers

• DL4RCE Member ✭✭

  May 2018 edited June 2020

  A sorted list of a certain value does not necessarily refer to overall performance. First the results are close and only from one source, it is a "value" that probably in real life does only matter for a small fraction of total users. Additionally "performance" means different things for different people. As the one operator is more focused on "remote" operation, the other one on "usability" and the next one on "contesting". Some also try to do a "price/performance" rating, some radios in the top list are 2, 3, 4 times as expensive for one transceiver as you basically get two transceivers with the 6600 series. From my humble opinion referring to a list is far away from real world. Sure, looks good but probably does not make too much sense. Last point regarding SDR tech. As some of the radios mentioned are no or only in part SDR tech, think about software. Every update (see latest PEN) is able to increase performance and every update to PowerSDR regarding usability.
  
  Regards,
  
  Volker, DL4RCE

  1
• Steve K9ZW Member ✭✭✭

  May 2018 edited May 2018

  Wayne - remember that the "Sherwood Numbers" are mostly single-sample.

  There are recent discussions where Rob Sherwood speaks to significant variations between units of the same make and model, ADC variations, and even variations in doing a second sampling set of tests on the same radio.

  What does that all mean?

  To use Rob Sherwood's own words:

  
  

  "Don’t have a coronary over a few dB here and there.  If you have a radio with a dynamic range of 90 dB vs. one that is 100 dB, I doubt you will ever know the difference.  When all we had were “up-conversion” radios for 20+ years, (TR-7 through the IC-756 Pro III for instance), all we had were 75 dB radios.   73, Rob Sherwood, NC0B"
  

  For simpler minds like mine, that basically mean "If a Radio's Tests are in the Top Couple Dozen Listings in the Sherwood Chart you Have a High Performance Radio."

  And I'd offer a further comment that "If your Radio's Tests are Listed anywhere in the Sherwood Chart you likely Have a Great Radio, so go make some contacts!"

  Maybe it is how the numbers read to us that gets us advocating lab differentials, rather than on the air differentials? 

  73

  Steve K9ZW 
  

  4
• Rich McCabe Member ✭✭

  May 2018 edited May 2018

  I agree with Steve. There are a lot more things that make or break a radio besides this single number even though it its an important one.  That said it was disappointing to see the 6600 so far down the list.  Have to wonder what the three hardware upgrades are?
  

  0
• Pat N6PAT Member ✭✭

  May 2018 edited September 2018

  Who cares about some list? My 6700 (which is at the top of the list by the way) works great and that puts it at the top of the only list that really matters - my list!
  

  0
• Gerald-K5SDR FlexRadio Employee ✭✭

  May 2018 edited April 2019

  I have a talk that I have presented at many ham conventions called, "Grokking Receiver Performance."  In that talk I show our FLEX-6700 at the top of the chart and tell everyone that the ranking is getting ridiculous (i.e. bunk).  I said that when we had one of the few radios above the 100 dB mark.  Sherwood has said many times that above about 90 dB IMD DR3 it doesn't matter and you won't know the difference as he was quoted again above.  Above about 90 dB or so we are all bragging about the length of our coax. 
  
  I think next we should start doing the measurements in hundredths of a dB.  ;>)
  
  Gerald

  2
• N4VLK Member ✭✭

  May 2018 edited June 2018

  i also agree with Steve. Listen to the May 8th Ham Radio Workshop Podcast with Eric Swartz, co-founder of Elecraft. The topic is "Understanding RF receiver specs.". He basically says the same thing.

  0
• Bill -VA3WTB Member ✭✭✭

  May 2018 edited June 2018

  But their are those who feel testing specs means everything, the end all. and make choices based on them.

  0
• Steve K9ZW Member ✭✭✭

  May 2018 edited May 2018

  It can be all of us - just human nature really. 

  Decision/Opinion making often develops granularity issues when we become biased to put too much or too little weight on the scale of measurable items.

  Then when we consider the supposedly "un-measurable" in our decision/opinion making things really get wild!

  I've sat in the pilot's lounge listening to folks get wound up on the theoretical differences in say "Cessna 170 model variations" completely forgetting that how the plane is rigged, what propeller in on the plane, the variations of engine tuning, and pilot technique are each bigger performance variables on whether the plane was a particular sub-model when built.

  I also overhead one old sage of a pilot say "that is all well and good, but statistics & specifications won't fly you anywhere." 

  Likewise with radios, what differences you as a specific operator may discern are the ONLY differences that matter in the end. 

  We all know folks who "chase the Sherwood Numbers" by striving to equip their shacks with whatever is at the top of the chart.  Even economics gives way to a passion to push that little bit further. 

  And then there are others who knock out endless QSOs sometimes using gear many would consider obsolete! 

  When we donate our old radios to other hams, charity, or for an overseas ham we know we are not burdening them with useless gear - yet intuitively we justify the donation in part because we are bettering our shack.  Likely we are, but by an increment smaller than what we tell ourselves, and much smaller than what we tell others.

  I have two Flex-6700s, a Flex-6600M, several older TenTec & SGC transceivers I enjoy, and then two complete Collins S-Line Stations (the doubles are because I have two QTHs I operate from).  All of them are FUN despite widely different test numbers and performance characteristics.  I make more QSOs with the FlexRadios, but also enjoy the challenge of running one of the Collins Stations.

  I'd hate to lose access to any of them, but again 80%+ of the time you will find my on the air with a FlexRadio!

  73

  Steve K9ZW

  1
• Bill -VA3WTB Member ✭✭✭

  May 2018 edited May 2018

  Lets say I buy a radio based on the specs alone, yes it beats out all the other radios, at the top. The numbers show that the radio should be a top performer, what ever that means, I mean after I install this wonder will I really tell the difference.
  
  The radio is up and running, wow works nice, BUT,  the buttons on the front are to close together and my **** fingers can't work them correctly. The menu's are hard to find, so many functions to wade through to find them. Each area is numbered 1 to 200 for settings. The radio has a panadapter, sort of, you can't make much out from looking at it.
  
  Well this radio is not so nice to operate, sort of clumsy,  but the specs!!!  Whoo hooo

  1
• KF4HR Member ✭✭

  May 2018 edited May 2018

  I know ham's who have purchased their equipment exclusively based on Rob Sherwood's Receiver chart.  While his chart numbers are interesting, I have my doubts whether most ham's know how to interpret the chart numbers (as they equate to real life operating), and I also doubt a few db one way or the other make any difference at all in real life operation. 
  
  Besides test numbers, what I'd like to see (hear) are actual recorded receiver comparisons, comparing receiver differences with lab created weak signals and adjacent interference. 
  
  Another issue that has been pointed out is, even given the exact same brand and model, test numbers can and do vary from unit to unit.  So the average ham has no way of really knowing whether their particular rig is worst, better, or meets Rob's chart numbers. 
  

  1
• Johan / SE3X Member

  May 2018 edited October 2018

  A bit surprised about the new Flex and it's placing on the list? But as the owner of a 6700 .. couldn't care less. Won't sell it, never. Agree most radios top 20 probably are great radios. Still I can easily live with having the no 1 on the list

  1
• Chris Tate - N6WM Member ✭✭

  May 2018 edited May 2018

  The bottom line is the 6600 series is a winning radio.  It is the ideal SDR for the contest community and performs spectactularly well. Rob doesn't measure things like low fatigue audio and such, something that really sets the platform apart from others.  And remember.. .its an SDR!  software changes can be continually applied, performance tweaked and improved. 
  
  Like apple used to say.. Think different!  I choose the flex 6600 as my contest rig of choice, and it, combined with the PGXL has put me in the winners circle..  up against competitors that needed 2 radios and amps to keep up,  and that was during the alpha test phase.
  
  In all likelihood the R.S. list has been made obsolete by SDR.  it just doesnt make sense anymore.  A new performance metric would probably be most useful.
  

  1
• Gary w8vi Member ✭✭

  May 2018 edited May 2018

  There is way too much variance for me in the test samples on the Sherwood list to accurately list the  top 15 receivers.
  
  The 6700 tested in 2014 and rated #1 with 108 db and another 6700 was tested in 2017 and was rated #18 with 96 db on 10 meters. If you have a 6700 do you really know where your receiver rates and could you ever tell the difference between the two?
  
  The newly released IC-R8600 is rated #2 with 107 db. A second sample of the R8600 was rated #16 with 98 db. So if you own a top level receiver what is your IMD DR3? Do you really know and could you tell the difference 10 db's one way or the other?
  
  Prior to my Flex 6300 and 6600 I had a IC-7800 that is rated #31 on the list with 80db. For me it was an excellent contest and DX rig with many positive features other than IMD DR3.

  1
• VK7WH Winston Member ✭✭

  May 2018 edited May 2018

  Same here, Johan. I will never contemplate sellind my 4 year old 6700, not because it's still number one on the list but because it is now an even better Radio than it was four years ago, and will continue to improve in the future. At my age, I am confident it will outlive me! Winston

  0
• Jerry Gardner Member

  May 2018 edited April 2019

  Am I the only one thinking that the discussion in this particular thread would be far different if the 6600M came out at the top of the Sherwood list than where it did? That there wouldn't be any of the "the numbers don't really matter" talk that pervades this thread?

  0
• Rich McCabe Member ✭✭

  May 2018 edited May 2018

  LOL, I am sure you are right
  

  0
• Gerald-K5SDR FlexRadio Employee ✭✭

  May 2018 edited May 2018

  I actually said that the numbers don’t really matter any more when the 6700 came out on top of the list about 5 years ago. I have it in print and in slide presentations. I showed the 6700 at the top of the chart on my slide and then said it is “pure bull. “ It is in my “Grokking Receiver Performance” presentation and article. I said since we are at the top of the list I It gave me the right to say it. The 6700 is still at the top of that list and I still say it is bull. You can’t use it. My coax is longer than yours. ;>).

  3
• Robert Lonn Member ✭✭

  May 2018 edited May 2018

  So my Icom IC-R8600 is Second on Bob List.. So when I received my radio last week that was the radio I wanted to do a comparison test. But my comparison to the 6600M radio over the weekend, was the Flex just had better RECOVERED AUDIO....
  
  What I could do in pulling out a weak signal on my Flex, I could not do with the Icom.. This Real World test tells me that the Flex will provide many more hours of enjoyable listening then my ICOM.. The ICOM is a Full SDR radio below 30 MHz, traditional conversion above that all the way out to 3GHz.. So every radio has its place in the ham shack..
  
  My Icom IC-9100 is my Satellite radio,, my Yaesu FT-1000mp Mark V is my 200 watt barefoot radio or Class A to drive my linear at 80 watts! My Yaesu FT-991 is my mobile/portable remote radio when out looking at the Stars and Zero cell service or WiFi.. BTW, I did power on the FT-991 to do some comparison to my Flex just to see how it performed..  I did no realize that the Yaesu Audio  was that bad now that I have a Flex to compare it to..
  
  I ran HRD software with the FT-991 as it was my first radio with a USB input.. WOW, HRD and FT-991, I was excited 2 years ago,, but SmartSDR puts that all to shame.. But hey,,, I am not telling you something most of you already know!!! HEY, 6 Meters is open!!
  
  Robert
  WA6PHN

  0
• Bill -VA3WTB Member ✭✭✭

  May 2018 edited May 2018

  The 6700 is still at the top of the so called list, what does that mean? As Gerald said, it's bull.

  0
• Rich McCabe Member ✭✭

  May 2018 edited May 2018

  The "top of the list" is pretty long these days.  I have had several on the first 2 or 3 pages on the Sherwood list and they were all fine radios. That said, I am on my third Flex now and have no interest in other rigs. Anyone that bases their purchase decision on that one sherwood number is crazy.  That said, if my 6600 was top of the list, I would be bragging it up. LOL 
  

  1
• Wayne Member ✭✭

  May 2018 edited May 2018

  He may say the same thing and agree but his rigs most of them populate most of the top 10 everytime so if he could save money by reducing those specs on his rigs he hasnt done it so they must be important to him even though he says otherwise.

  0
• Wayne Member ✭✭

  May 2018 edited May 2018

  It all depends on how you operate if you have the best rig and not a clue about setting rf gain dsp etc. then you may thimk its terrible but the issue may be the loose nut in front of the rig!

  0
• Wayne Member ✭✭

  May 2018 edited May 2018

  When your not the lead dog the views all the same just a **** :-)

  0
• Wayne Member ✭✭

  May 2018 edited May 2018

  I know thats right!

  0
• Ria Member ✭✭

  May 2018 edited November 2019

  Beyond about 80dB it doesn't matter much. There is much more you can do with what is on your tower rather than what is in the shack. I've always said that to people - any of the top radios is a good radio. 
  
  What sets apart Flex for me is the whole ecosystem - 
  
  Ethernet control. Few offer it and none do it as well as Flex does. 
  Remote operation. Few offer it, and nobody does it turn key like Flex does. 
  
  So many built in extras in a Flex that are just an afterthought with most radios. For example a simple thing like an interlock. One op at a top contest station using a competitor's new model radio quietly told me he wishes it had an interlock input, and that he hated having to rig something up. I told him Flex has it... and smiled. Even DAX. How many fight with sound card interfaces? I've had four. Three of them were absolute garbage. One had a strange hum that raised my noise floor about 5-6dB. I have none of that with DAX. I don't have to even pay for a third party license (virtual audio cable). 
  
  Ability to customize your way of operating. While some may disagree with this and say that you have to "keep it simple" I think that customization is good. Flex offers plenty of this, plenty more than the competitition. The demand is clearly there based on proliferation of third party apps.
  
  So many ways to operate - knobs or no knobs, boom mic, headset, put the radio in a barn near the tower, keep on your desk, etc. PC, Mac, iOS, Maestro. 
  
  Power Genius XL "no compromises" amplifier with easy plug and play setup. When you can dual CQ on RTTY with a single amp, then you can even talk about being in the same class. Otherwise, forget it. 
  
  I got one because I wanted a good performing radio WITH tight integration into my station. I get all of that in my Flex-6700. 

  2
• Robert Lonn Member ✭✭

  May 2018 edited November 2019

  Interesting Comments,,, Hey, Has anyone used their remote software on an Airplane???  Normally I am watching a movie, stored on my iPad,,  on my 4 hour flight from Atlanta to San Diego, Delta Airlines! Their WiFi is not that bad! I wonder how well the remote software would work?? CQ, CQ, CQ, this is WA6PHN Remote Airplane at 35,000 feet!!! :-) 

  0
• Gerald-K5SDR FlexRadio Employee ✭✭

  May 2018 edited May 2018

  This is a direct quote from a public email from Sherwood today. “One CTU slide this year has 17 different transceivers rated from 90 dB to 108 dB. Everyone one of them is a completely viable contest / DX or DXpedition radio, limited by other aspects.”

  0
• Ria Member ✭✭

  May 2018 edited May 2018

  I have. The enhanced speed service on Delta via GoGo works better.  But apart from that one time on the radio I just usually enjoy the free cocktails and take a nap. 

  0
• Robert Lonn Member ✭✭

  May 2018 edited May 2018

  They say the more you drink the better the audio will sound!!

  2
• Rich McCabe Member ✭✭

  May 2018 edited May 2018

  That is possible with a lot of things. My code sending improves drastically after a couple adult beverages.  At least I think so
  

  2