Sort Sherwood individual receiver tests by column! It’s a large table but scroll-able horizontally using the standard slider. Look for the black caret symbol beside each column name to resort as you wish. The table is current circa March 5, 2022.
I’ve added the Sherwood Performance Index (SPI) as an extra column. It was developed in my research published in the ARRL National Contesting Journal in 2020. It’s a “linear composite” of all nine of NC0B’s bench tests, weighted according to their commonality in each evaluated rig. So, it’s a broader measure of the overall receive performance than the narrow dynamic range that Rob uses to sort his table. But, no doubt, Rob’s thesis that “close in” dynamic range is the single best metric for CW contest operators stands.
Please note: there are a few “double entries” in Rob’s spreadsheet for the same rig. It’s because he has performed two independent tests on the same rig after some change by the manufacturer. See his table notes for details!
For any data content questions, contact Rob NC0B. I’m just taking the data with Rob’s permission to facilitate sorting on any column, not just the close-in dynamic range as he does on his website. I’ve separated the footnotes from the data in each table cell so it won’t interfere with your sort. They are in a separate table below. I’ve also placed them in an additional table with their meaning below the bench test results to see if they interest you. It’s important to read Rob’s documentation to understand the bench measurements (shown below).
If you would like to see the relationship between the SPI and the narrow dynamic range measurements, click HERE.
To better understand the relationship between ranking and the metric used to rank these rigs, see HERE.
The Sortable Sherwood Table will open in a new page by clicking HERE.
If you’d like the Excel spreadsheet extracted via Rob’s website, download it HERE.
Here are Rob’s field descriptions for his table (be sure to read them):
TermsExplainedSherwoodTableofReceiverPerformance-RevFHere are the footnotes for each rig that Rob made in his tables.
| Footnote | Note Content |
|---|---|
| General Note: | 3 dB blocking (gain compression) test done at 100 kHz to eliminate phase noise interaction |
| N.A. | Data not available |
| F.L. | Filter limited, no measurement was possible due to signal leakage around filter |
| a | Measured with SSB filter |
| b0 | No preamp actuated |
| b | Built-in Preamp actuated |
| b1 | Built-in Preamp 2 actuated |
| b2 | Built-in Preamp set at 20 dB. Adjustable to 10, 20 or 30 dB |
| b3 | Built-in Preamp set at 16 dB |
| b4 | Built-in Preamp set at 32 dB |
| c | Readings would have been lower if 2-kHz spacing had been possible |
| d | Dynamic Range is 90-dB at 100-kHz spacing |
| e | 20-kHz Dynamic Range is 66-dB |
| f | Measurement was Phase-Noise Limited = ARRL RMDR (Reciprocal Mixing Dynamic Range) |
| g | Audio DSP Enabled |
| h | AGC Off |
| i | At 1 kHz dynamic also 95 dB but with 300 Hz roofing filter enabled |
| j | At 1 kHz, noise limited to 68 dB |
| k | At 1 kHz dynamic range was 66 dB |
| l | (lowercase L) Reserved |
| m | Receiver was optimized by Malcom Technical Support for best dynamic range |
| n | Measured with 3 kHz roofing filter |
| o | Measured with 6 kHz roofing filter |
| p | with 200 Hz 5-pole filter |
| q | with 400 Hz 8-pole filter |
| r | with 500 Hz 5-pole filter |
| s | Using ARRL 3-Hz bandwidth blocking method |
| t | with optional roofing filter |
| u | without optional roofing filter |
| v | At 1 kHz performance is opposite sideband rejection limited |
| w | At 1 kHz dynamic range is 104 dB |
| x | "Long Form" report available by e-mail request._x000D_ 2-kHz RMDR: 6M=91dB, 10M=92dB, 12&15&20M=87dB, 17M=85dB, 30M=98dB, 40M=92dB, 80M=94dB & 160M=95dB |
| y | DR3=108 dB with 20 dB preamp ON, and 99 dB with preamp OFF. Otherwise dynamic range independent of signal spacing._x000D_ NOTE: Tests in 2017 of a second 6700, and by the ARRL of a 6500, no longer measured a dynamic-range increase with the preamp ON. The 108 dB value is no longer valid. 2 kHz dynamic range is 99 dB, same as 6600M. As with any radio, only use a preamp if it improves copy, and usually only on 15m and up. |
| z | The low-side dynamic range was 76 dB, while the high-side dynamic range was 70._x000D_ NOTE: This may imply the roofing filter was asymmetrical, and likely a sample variation. |
| aa | Measured using 1.2 kHz roofing filter. |
| ab | Measured with IP+ ON. |
| ac | Measured with dither and random OFF_x000D_ NOTE: Icom calls "dither and random" IP+. Noise floor may be affected by dither and random. |
| ad | Measured with Dither and Random ON_x000D_ NOTE: Dither and Random convert intermodulation products into broadband noise. |
| ae | AGC threshold adjustable_x000D_ NOTE: AGC threshold should be set about 6 dB above band noise. |
| af | Measured with third test tone._x000D_ NOTE: ARRL may test dynamic range (DR3) of direct-sampling radios with a third test tone to approximate a crowded band. The validity of this test method is questionable. |
| ag | DR3=96 dB with 20 dB Preamp ON. (99 dB Preamp OFF) Otherwise dynamic range independent of signal spacing._x000D_ NOTE: Testing of 2nd sample made on 10 meters while investigating IFSS* curves. Similar testing of 2nd sample of K3S, also made on 10 meters. * IFSS = Interference free signal strength. |
| ah | NOTE: Testing of 2nd sample made on 10 meters while investigating IFSS* curves. Similar testing of 2nd sample of Flex Radio 6700, also made on 10 meters. * IFSS = Interference free signal strength. |
| ai | NOTE: Dynamic range testing of a second 6300 sample resulted in a modestly higher dyanmic range measurement. |
| aj | NOTE: Test data for 6600M is after May 2018 PEN (Product Enhancement Notice). Due to the insertion loss of 7-pole bandpass filters on the contest bands, recommend +16 dB preamp during daytime on 80 -17 meters if in a quiet location. 15 - 6 meters may require +32dB preamp for an adequate noise floor.Tested with Alpha v. 2.2.7 software. |
| ak | Some variation in dynamic range was noted after an extended warm-up. |
| 6 | 6 meter data, preamp ON |
| 10 | 10 meter data, preamp 2 ON |
| 2 | 2 meter data, preamp ON |
| 70 | 70cm, preamp ON. RMDR limited |