One of the most valuable tools for amateurs worldwide to use when evaluating HF rigs is the set of bench tests that Rob Sherwood NC0B has provided for quite a number of years now. He ranks the receive tests by his favorite metric: narrow dynamic range in dB. It’s a key for CW contest operators (pun intended) which he is in spades. But it is a frequent question from readers of Rob’s table: why can’t I sort it on another criterion? Especially if I’m not a CW contest operator?
Well, now you can! Working directly with Rob NC0B, I’ve taken his latest receive test data and made a sortable table for the Sherwood Test Results. They are circa March 5, 2022. It’s at my companion site, foxmikehotel.com at this link. I plan to update it when Rob adds new radios to his Table.
I’ve also added sub-pages to illustrate some facets of the data. Based on my work over the past couple of years with adding price and consumer satisfaction data for each rig in his Table, I’ve learned that it’s important for readers to better understand both Rob’s tests and his ranking metric. In that research published in the ARRL’s National Contesting Journal, I created a composite of all nine of Rob’s bench tests which I called the Sherwood Performance Index (SPI). It is a broader assessment of receive performance than the narrow dynamic range. But it is not intended to be a replacement for Rob’s preferred metric, only a complement.
Thus far, I’ve added two interactive charts that will help the viewer better understand Rob’s table results. More may come.
One chart shows how the reader can “out-rank” themselves by ONLY focusing on how a rig is ranked on the narrow dynamic range measurement. Rob tells readers not to take the exact ranking as the only aspect of a rig for the top ten rigs are all very good on receive. This interactive graphic will allow the viewer to see how some rigs “bunch” together with almost identical narrow dynamic range but are, indeed, sequential ranked because of numerical differences that simply do not make much difference as realized in the rig’s actual performance. But, ever hear an athletic team cheer this after a game? We’re Number 10! We’re Number 10! I didn’t think so. But Number 10 might be just as good as Number 1 on the metric determining the ranking. You have to look at the data behind the ranking. This chart makes it easy.
A second chart demonstrates how Rob’s ranking variable, narrow dynamic range, relates to the composite SPI. You’ll find some interesting results from that chart, seeing how narrow dynamic range is important but there is more to some rigs than that. Especially if you’re not a contest operator, CW or otherwise.
As he has stated in various podcast interviews (including mine on the ICQ Podcast and recently on the Ham Radio Workbench), he started these bench tests for his own use as a CW contest operator. Rob disagreed with the ARRL’s tests as published in a review of the classic Drake R-4C receiver. So he created what he thought was a suite of appropriate bench tests. And the rest is history. For transceivers and receivers (“rigs”) over a 50 year period!
Here’s a trend line for the SPI by year over the horizon of rigs in his Table, circa November 2019. We are in the best period yet for receive performance in terms of Rob’s test suite. But now you can sort the Sherwood Table on any of his tests including the composite SPI that I added to asses your rig of choice.
Rob codes his website in conventional HTML. He recently had to suddenly change hosting providers. So he’s had enough on his plate with all of the other engineering contributions he makes almost daily to various email lists and groups. So while he could alter the HTML code to provide the ability to sort his table, I appreciate his spending his retirement time continuing to assist the amateur radio community as he does now. I hope that this offering of a Sortable Sherwood Table on my companion website will help the reader better understand this terrific tool as well as help Rob, too.