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Author Topic: Choosing a rig and Sherwood's list  (Read 4716 times)

AC7CW

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Choosing a rig and Sherwood's list
« on: March 06, 2020, 04:37:31 PM »

Dan Sherwood has done a lot of work to build his repository of test info. It's at http://www.sherweng.com/table.html for the few that are unfamiliar with it. He ranks rigs by ability to operate with close spaced interference. That might not mean a lot for a casual operator though. I'm not a contester so I am wondering what parameter would be the next in importance were I sorting the list to choose a rig. The data can be copied and put in a spreadsheet. I sorted by noise floor and a TS-830 comes to the top of the list. Other radios rate higher under different circumstances such as preamp turned on but the TS-830 at the top of the list! That rig is very highly rated by casual ops so maybe noise floor is the parameter to work with?
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W9IQ

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Re: Choosing a rig and Sherwood's list
« Reply #1 on: March 06, 2020, 05:49:04 PM »

Due to the prevalent RFI from consumer electronics, noise floor is now a meaningless metric for most hams.

- Glenn W9IQ
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- Glenn W9IQ

God runs electromagnetics on Monday, Wednesday and Friday by the wave theory and the devil runs it on Tuesday, Thursday and Saturday by the Quantum theory.

KH6AQ

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Re: Choosing a rig and Sherwood's list
« Reply #2 on: March 06, 2020, 06:08:48 PM »

I believe CW contesting is where maximum receiver performance is needed and Dynamic Range Narrow Spaced is the parameter of interest. I've owned several transceivers that did not hold up under 160 meter contesting. The two I've owned that were excellent for CW contesting are the Elecraft K3 and the Icom IC-7300 with narrow spaced dynamic range of 101 and 97 dB respectively. One of several that were nearly unusable under 160 meter contest conditions is the Kenwood TD570S at 69 dB. In the paper cited below, Bob Sherwood says 80 dB or better at 2 kHz (that is narrow spaced dynamic range) is needed for CW.   

Here's a link to the paper Transceiver Performance and how do we measure it?, by Bob Sherwood.

     "Contesters – DXers – Pileup operators need a good receiver for SSB and an even better receiver for CW."

Near the end of the paper he presents a the list Considerations in Choosing a Transceiver.

http://www.na0tc.org/lib/exe/fetch.php?media=technical:transceiver_performance_and_how_do_we_measure_it-_rob_sherwood_nc0b-285-techconnect-1w.pdf

Sherwood Receiver Test Data
http://www.sherweng.com/table.html


 
« Last Edit: March 06, 2020, 06:29:28 PM by KH6AQ »
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N5PG

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Re: Choosing a rig and Sherwood's list
« Reply #3 on: March 06, 2020, 08:26:29 PM »

Don't forget there's much more to picking a rig than good Sherwood numbers. You want something that's also a good ergonomic fit to your operating likes and dislikes eg how many choices are hidden in multiple menus rather than being a knob(s) on the front panel and things like that. How large is it ? How heavy is it?  And so on.
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AF5CC

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Re: Choosing a rig and Sherwood's list
« Reply #4 on: March 06, 2020, 08:27:41 PM »

 A lot of the choice will involve what your activities are in ham radio and what the QTH is like.  With all of the noise we get today from consumer electronics, if you live in a suburban or urban environment, a good noise blanker and noise reduction might be the most important feature.  If you live in a rural area, then that might not be much of a factor.

If you are not into contesting but are into DXing, you probably want a radio with dual receive and a good noise floor.  Not as important if you spend most of your time on traffic nets or just ragchewing.  Creature comforts like a voice recorder and CW memory keyer are always nice, same for a good built in autotuner.

Most important are ergonomics and it has to be a radio you enjoy operating.  If you don't like the layout of the radio and how you interface with it, good dynamic range or other features aren't very important.

73 John W5TD
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N6YFM

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Re: Choosing a rig and Sherwood's list
« Reply #5 on: March 06, 2020, 10:15:31 PM »

I don't know CW;  my Icom 7300 does really great for RTTY contests.
My Flex 6600 does even better.   I still don't know CW.   I did not look
at Sherwood's list before buying either rig, but HE own's and likes his
Icom 7300. :-)

Neal
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K4FMH

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Re: Choosing a rig and Sherwood's list
« Reply #6 on: March 07, 2020, 03:44:49 AM »

His name is Rob Sherwood. For details on using his Tables, see https://www.icqpodcast.com/download-the-show/2019/9/15/icq-podcast-episode-305-sherwood-engineering

73,

Frank
K4FMH
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W1VT

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Re: Choosing a rig and Sherwood's list
« Reply #7 on: March 07, 2020, 04:55:18 AM »

Dual receive is a great feature for net operation.  You can send folks off to another frequency and listen to how they are doing.  You can also make sure that the frequency is unused before sending them there--not just a brief listen, but continuously monitoring it while running a net.

Dual receive is also great for CW DXing, as finding stations giving reports is an effective way of tracking the listening frequency.

Zak W1VT
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K8AC

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Re: Choosing a rig and Sherwood's list
« Reply #8 on: March 07, 2020, 11:27:21 AM »

Quote
Dual receive is also great for CW DXing, as finding stations giving reports is an effective way of tracking the listening frequency.

Many people would agree with that.  I prefer using a high resolution panadaptor where I can not only see all the folks who think they're working the DX station all at once, but I can also see the timing of the exchanges, which sometimes helps identify the station who is REALLY working the DX station. 

73, K8AC
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W2BLC

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Re: Choosing a rig and Sherwood's list
« Reply #9 on: March 07, 2020, 01:45:51 PM »

Any rig in the top 20 of Sherwood's list will outperform the abilities of most antennas and locations. QRM/QRM etc. All these factors will degrade reception more than you gain with a rig's great capabilities.
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K8AC

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Re: Choosing a rig and Sherwood's list
« Reply #10 on: March 08, 2020, 06:33:50 AM »

Any rig in the top 20 of Sherwood's list will outperform the abilities of most antennas and locations. QRM/QRM etc. All these factors will degrade reception more than you gain with a rig's great capabilities.

I'd like to add to that comment like this: "Any rig in the top 20 of Sherwood's list will outperform the abilities of most antennas, locations and operators."

From operator comments over the past few years on these forums, it's clear that very few operators have any idea what the effects of a receiver performing poorly in the narrow-spaced IMD arena are, or what one can do to alleviate the symptoms when they occur.  I've owned a couple of transceivers that were marginal in this area, and the only time any symptoms were observed were on 160 and 20 meters during contests where the band was loaded with very strong signals.  Even then, the workaround was pretty simple - switch a bit of attenuation into the receiver antenna input and the IMD disappeared.  As W8JI pointed out some time ago, any narrow-spaced IMD number of 80 or greater is adequate most of the time. 
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WA2ONH

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Re: Choosing a rig and Sherwood's list
« Reply #11 on: March 08, 2020, 08:09:20 AM »

His name is Rob Sherwood. For details on using his Tables, see https://www.icqpodcast.com/download-the-show/2019/9/15/icq-podcast-episode-305-sherwood-engineering

The Sept 15 2019 Podcast can be downloaded as a MP3 file and is 78,117kb Size; Total show runs approx 1-hour and 50-minutes

The Rob Sherwood interview starts at the 1-hour and 2-minute mark. Very interesting.
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W2BLC

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Re: Choosing a rig and Sherwood's list
« Reply #12 on: April 14, 2020, 06:32:23 AM »

Point to remember: The highest rated rigs are all generally interchangeable in the field - the differences being personal mechanical preferences (like your buttons where?). The great equalizer is the noise conditions we operate under and have little control over. The numbers are lab report.

In short, I feel that a 7300 is able to do 99% as well, in most conditions and uses, as any of the over $5000+ rigs. Of course, there are no bragging rights. Unfortunately, the latter is very important to some ops.

There is a lot of pleasure and enjoyment to a 7300 and a MyAntennas end fed all band antenna. You could call it a $1000 station.

The real key is to get on the air with something and enjoy what you have!
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KB9OAK

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Re: Choosing a rig and Sherwood's list
« Reply #13 on: April 14, 2020, 06:26:36 PM »

My 706mk2g made the top 100, :o but I'm in no hurry to chuck it based on some list. I wanted something versatile and easy on my wallet @ under $600 used with all the filters from my local HRO, it fit the bill.
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AC7CW

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Re: Choosing a rig and Sherwood's list
« Reply #14 on: April 14, 2020, 06:51:32 PM »

It will always be true that a perfect plan for tomorrow will ruin a good plan for today. Personally I'm starting out my shack build with a FT-991A. My club having Fusion repeaters being one reason for that and the band coverage being another. If I buy a high-end rig it will be fine as a backup. It certainly won't work if I'm trying to dig weak signals out of the noise in a contest.

I had some fun with Rob Sherwood's list: copied it into excel, removed extraneous data keeping the best noise floor data for each rig and sorted by that. The rigs at the top of that sort were some of the all time most desirable, best spoken of rigs. It's true that in our ordinary noisy environments noise floor doesn't mean much but nonetheless....
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