Receiver test results

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zl2taw

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Hey Martin, I dont really understand the table, whats the column that sort of tells the story for being better or worse

I have a R-5000 but it all looks gobbley gook to me, sorry if its a dumb question
 

majoco

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Yes, it's strange that they took "Narrow Dynamic Range" as the parameter on which to sort. That's probably why the relatively deaf FTdx-5000 came top of the list!

I guess most people when looking at the specs of a radio would go for 'sensitivity' first but of course thats not everything, 'receiver noise' would come high on the list and 'blocking' in areas where there were high powered nearby transmitters - Europe on the 49m band at night is a jumble of strong signals.

I'll try to get the data into a spreadsheet so I can sort on any parameter - could be more useful.
 

k9rzz

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For my own use, BCB DX, looking for trans Atlantic sigs on the 9khz splits, I go by the dynamic range with a goal of >95 (>100 even better). Then I know I can hook up the biggest antenna I can muster, and have confidence that the receiver will not overload.
 

prcguy

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Sensitivity is probably at the bottom of the needed traits for a good HF receiver except above around 20MHz or so. HF reception is driven by signal to noise ratio and noise is probably several magnitudes higher than the noise figure of any receiver on the lower HF bands. Going from 1uv to .1uv sensitivity makes no difference at all on the lower bands.

The Sherwood site is a good one and he does concentrate on the parameters that make a world class receiver stand out and these are very expensive traits to improve upon.
prcguy


Yes, it's strange that they took "Narrow Dynamic Range" as the parameter on which to sort. That's probably why the relatively deaf FTdx-5000 came top of the list!

I guess most people when looking at the specs of a radio would go for 'sensitivity' first but of course thats not everything, 'receiver noise' would come high on the list and 'blocking' in areas where there were high powered nearby transmitters - Europe on the 49m band at night is a jumble of strong signals.

I'll try to get the data into a spreadsheet so I can sort on any parameter - could be more useful.
 

Token

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I don't think anyone ever said the 515 was a slug, it just got a little long in the tooth.

There are many things to consider when looking at receiver performance. Dynamic Range on Narrow spaced signals gives a relatively good look at close signal performance, a problem for many listeners, and that may be why they selected to sort on that value.

In the interest of full disclosure, I do have the FTDX-5000, but I do not feel I am responding in defense of that radio, or any specific radio. For that matter I own 3 of the 4 top receivers on that list, the FTDX-5000 (owned it before they did the test), Microtelecom Perseus, and FLEX-5000A.

majoco, not sure why you used the term “relatively deaf” in association with the FTDX-5000? Unless you just mean it as compared to the raw sensitivity of the -515 (0.1 microVolt), and the difference between 0.1 and 0.13 microvolt is VERY minor (about 2 dB). The noise floor of -141 dBm and sensitivity of 0.13 microVolt puts the FTDX-5000 in the top 10 or so receivers of all tested on that list using just those two specifications (6 equal or better noise floor, 18 equal or better sens). For the FTDX-5000 the 9 dB improvement in Wide Dynamic Range, the 24 dB improvement in Narrow Dynamic Range, the 17 dB better LO noise, the 24 dB better 100 kHz Blocking, and the 10 dB ultimate Filter Performance, all add up to a radio that is significantly, not just a little, better in every measurable way (compared with the NRD-515, Kenwood TS-830, Kenwood TS-430S, and similar radios with 0.1 microVolt sens) with the exception of raw sensitivity.

And raw sensitivity is not really an issue for most users in the HF range. Unless you are in a location with very low noise, have unusual atmospheric conidtions yielding lower than normal HF noise levels, and looking at a signal with nothing else even close to it you cannot really use that sensitivity, but you can use all those other factors. I do live in a low noise location and my Icom R8500 has a sensitivity of 0.11 microVolt but my FTDX-5000 regularly pulls out weak signals the R8500 has no hope of showing as more than an unusable something. I also have a Kenwood TS-430S, listed on the Sherwood list with 0.1 microVolt, and the same thing applies, on the same antenna, under the same conditions, the FTDX-5000 regularly makes signals 100% copy that the -430S renders as “yeah, there is something there, but I can’t understand it”. I cannot think of one time the 430S or the 8500 has ever pulled out a signal the FTDX-5000 could not. I can remember a few instances when one or the other of them did pull out a signal the Perseus could not, despite the Perseus being listed third on the Sherwood list, but I can also think of more times the Perseus pulled out signals the 430S or 8500 could not. Then again the Perseus has a relatively dismal 0.6 microVolt sensitivity, more than 13 dB worse than the 430S or 8500 (or your -515), so weak signals completely in the clear are not the Perseus strength.

A lot of individual specifications mean very little on their own, it is the complete package that matters.

I sure wish they would do a set of measurements on the Excalibur. On paper it should be a bit better than the Perseus in most ways, maybe not Front End Selectivity, since the Excalibur has a wide open front end. The Excalibur Pro should beat the Perseus in every way I see listed (not sure about LO Noise).

T!
 
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majoco

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Token said:
majoco, not sure why you used the term “relatively deaf” in association with the FTDX-5000?
I was just looking at the figure with preamps off. No slur intended!

I guess turning preamps off will increase dynamic range, almost the equivalent of turning an attenuator on?
 

SCPD

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The other thing to note on that site is that they (at least not that I've seen) don't re-test the newer radios on a regular basis. They do one measurement and that's it.

With all of the firmware updates for Icom, Elecraft and perhaps Yaesu, it's very possible that those measurements have changed somewhat. Granted, they won't likely change by a great deal -- but a remeasurement should be done (if anything) just to compare the numbers.

RE: The Perseus

I would have to question those sensitivity numbers as my Perseus will easily match my Icom 7600.

I have noticed with the Perseus that I can "hear" (a weak signal but not see anything in the waterfall to tell me it's there.
 

Token

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RE: The Perseus

I would have to question those sensitivity numbers as my Perseus will easily match my Icom 7600.

I have noticed with the Perseus that I can "hear" (a weak signal but not see anything in the waterfall to tell me it's there.
I find kind of the same thing with the Perseus waterfall, I can sometimes detect it by ear before it clearly shows on the waterfall. The waterfall just is not good for very weak signals, but works well once they reach the S1 or so stage. So weak sigs are OK, very weak sigs the advantage is by ear. The Excalibur and the SpectraVue waterfalls are better for very weak signals. They are just easier to tweak to show very weak signals, but the Peresus display can be adjusted, I like mine a little contrasty.

I would have to say the Perseus numbers are pretty close but a bit stingy on the Sherwood list, I have measured the sensitvity of mine (preamp on) and in SSB it is about 0.4 microVolt (-115 dBm) at 10 dB S/N for 3 kHz BW and 14000 kHz. Slightly better than the Sherwood numbers (depending on their test criteria, what BW was it done at?), but not Worlds apart.

T!
 

prcguy

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Sherwood does retest in some cases like the Elecraft K2 where the original did not seem to meet specs. In most cases Shwewood relies on radios sent in as Rob can't possibly buy one of everything out there to test.
prcguy




The other thing to note on that site is that they (at least not that I've seen) don't re-test the newer radios on a regular basis. They do one measurement and that's it.

With all of the firmware updates for Icom, Elecraft and perhaps Yaesu, it's very possible that those measurements have changed somewhat. Granted, they won't likely change by a great deal -- but a remeasurement should be done (if anything) just to compare the numbers.

RE: The Perseus

I would have to question those sensitivity numbers as my Perseus will easily match my Icom 7600.

I have noticed with the Perseus that I can "hear" (a weak signal but not see anything in the waterfall to tell me it's there.
 

Token

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Sherwood does retest in some cases like the Elecraft K2 where the original did not seem to meet specs. In most cases Shwewood relies on radios sent in as Rob can't possibly buy one of everything out there to test.
prcguy
I am pretty sure they also retested the FT-2000 after it seems to have turned in such a dismal performance compared to the QST test. But agiant he results were not good, which confuses me because my own testing indicates it is quite a bit better than the Sherwood list would support.

T!
 
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prcguy

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I've used a lot of radios on the list and would agree with the pecking order on the ones I'm familiar with.

The tests also answer why most people I know who traded in their Icom 706MKIIGs for a new IC-7000 want their 706s back due to the drop in receiver performance.
prcguy



I am pretty sure they also retested the FT-2000 after it seems to have turned in such a dismal performance compared to the QST test. But agiant he results were not good, which confuses me because my own testing indicates it is quite a bit better than the Sherwood list would support.

T!
 

Token

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I've used a lot of radios on the list and would agree with the pecking order on the ones I'm familiar with.

The tests also answer why most people I know who traded in their Icom 706MKIIGs for a new IC-7000 want their 706s back due to the drop in receiver performance.
prcguy
In general I also agree with the list, and yes I have used quite a few of the radios on the list. I consider the FT-2000 to be a flyer on the list. I am pretty sure it is better than its position on the list would indicate (I have measured its performance myself) but I have no explanation for why they got the results they did.

For sure my FT-2000 outperforms my Yaesu FRG-7700, my Icom R-75, or my Kenwood TS430S, in every way I can tell (possible exception the NB), and yet all three of those radios are above it on the list.

T!
 

ratboy

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I had a Gilfer modified NRD-515 for almost 30 years, and I loved it. It made pretty much anything I ever put up against it look pretty sad on SSB/RTTY stuff. On AM, well, it had some issues with audio quality, partially solvable by finding the right speaker, and the right speaker is NOT the crappy factory one! I used a RS minimus 7 speaker, and it was pretty pleasant. If I ever have the cash, the 515 is on my list to buy again.
 

majoco

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The biggest improvement I made to my NRD515 AM audio was to put in an emitter follower buffer amplifier just before the am detector diode - cleaned up lots the 'wooliness' and I think it made some improvement to the SSB clarity too - both detectors are always connected, just the outputs get switched.
 

hertzian

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For the 515 (and a number of other receivers) you may want to look at Kiwa Electronics for audio improvements and different IF filters:

Kiwa Electronics

I've used a couple of their self-installing kits for audio and IF filtering, and they worked well for me. Non-polarized quality caps and metal film resistors in the dc supply paths did reduce my long-term listening fatigue. Swapping out some of the IF filters for BC listening use helped too. Worth a look.
 

majoco

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Been there, done that, got the empty packet! Yes, done the Kiwa audio mod - makes an improvement with an external speaker but as I take the low-level line out and feed that into a mixer with good speakers it hasn't made much difference to that. I have the Sherwood AM filter mod kit on the way as we speak.....
 
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