IC-R8500 HF performance vs De1103

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perseus68

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HF performance vs De1103

Ok I know I'm comparing apples to oranges but I'm almost sure that some of you compared the IC-R8500 and the De1103 side by side at HF.

I'm really curious to know who wins in terms of sensitivity.
Let's neglect selectivity because I'm almost sure he IC-R8500 has an edge here.

Anybody did this crazy comparison?

73s
Marco
 

perseus68

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I know, it had to be a provocation for you guys but, seriously, there are people who gave enthusiastic reviews of their De1103 and posted many videos on Youtube so that I was curious to know how it could compare against the bulldozer:)
Let's see if somebody shows up here.
 

SCPD

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If I could only understand what that guy says in the caption...
Translation:

I tried to compare the IC DE1103-scan at the same time in different locations 15500KHz ~ 15600KHz in each LOOP7 10mWire and R8500. DE1103 is a mountain near his home (mostly man-made noise-free) at reception in 10mWire, IC-R8500 is a home (surrounded by park) is in receipt of ΔLOOP7. Reception in the nearby mountains, hardly captures the signal as the noise floor. DE1103 is received in the office came, R. Australia (15560KHz and 15515KHz) HCJB and (15525KHz) was 3station's. At home while receiving the noise floor is quite out. LOOP7 will pick up noise, so that indoor equipment has been installed and fixed on an outdoor shed. I think that depends on location, IC-HCJB had just been received well in the R8500.
 

zl2taw

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guess it comes down to the noise floor, if the signal is below the noise floor there is no radio thats going to pull the signal through that
 

perseus68

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That guy on Youtube just replied:

"@perseus68 Hello! Thank you for the comment.
DE1103 is reception by 10mWire in the mountain of the neighborhood with comparatively few Man-made noises.
IC-R8500 is reception by Loop7 at a house with many Man-made noises.
The thing which I would like to say by this video is fully being unable to demonstrate performance on a location with many noises, even if it uses the antenna as which a highly efficient receiver may be sufficient. "

Anybody knows what kind of beast the Loop7 is?
 

corbintechboy

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Considering my 1103 does not even stand up to my E1, I don't know what to say.

But I think the E1 would even hold advantage to the 8500, the E1 is a proper HF radio.
 

mitaux8030

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Don't write off the Degen quite yet. If you connect a big longwire, the R8500 is going to win, no question. The 1103 will overload, squirm and complain with so much signal. But if you're only using a little short wire antenna, lets say 10 feet long, then perhaps the Degen has an equal chance of pulling even.
Tell you what, I'll compare a TS430 and the Degen with a small signal generator, under lab conditions and let you know the result. Yeah this test isn't real world conditions, but you asked a question about sensitivity alone and the answer might be suprising.
 

mitaux8030

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The results are in. Even managed to get my hands on a TS2000 for comparitive testing. Approximating the 'minimum disceranable signal' test where you feed in a signal that is only just audible to your ears with the volume up at a healthy level, testing was carried out in anticipation.

In general, on the lower bands the Degen was actually more sensitive! I kid you not. Only by a few fractions of a microvolt, but none the less, an equivalent 0.08uV signal stood out more on the Degen than either of the Kenwoods. As the frequency climbed, the Kenwoods started to match and overtook the Degen. By 28 MHz, the Kenwood TS2000 was winning, with the TS430 only about 1 or 2dB behind, and the Degen a further 3dB behind that (sorry, the sig-gen is calibrated in dBm only so its easier for me to talk dBm rather than uV). All my testing was carried out using SSB modes.
And what about the AM BCB? Normally ham radios are hog-tied in this area of the spectrum with some extra fixed attenuation, but both ham rigs here had this fixed attenauation removed for DXing in this band. Even so, would they still be decently sensitive? Answer: yes! The TS430 really shone here, with even a -130dBm signal - the lowest this sig-gen will go - it was still quite plainly audible. So lets call this result -133dBm for the TS430. The TS2000 needed about -128 dBm to only just be audible, and the Degen needed -126dBm to be heard. A mixed bag of results there.

But in general, the little Degen was within a few dB of the big rigs across the spectrum. Of course in a real world test away from the bench, the Kenwoods would be all over the Degen in terms of selectivity, being able to handle a large antenna, compression point etc. And thats even before the interference fighting features of teh Kenwoods come in to play. But in a low noise environment, with a short wire antenna, the Degen wouldn't embarrass itself compared to other rigs costing twenty times as much.
 

majoco

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OK, I'll send you my Degen for 10years loan and you can send me your R8500. In 10years time I'll publish a full evaluation here.

Fair enough?:)
 

perseus68

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The results are in. Even managed to get my hands on a TS2000 for comparitive testing. Approximating the 'minimum disceranable signal' test where you feed in a signal that is only just audible to your ears with the volume up at a healthy level, testing was carried out in anticipation.

In general, on the lower bands the Degen was actually more sensitive! I kid you not. Only by a few fractions of a microvolt, but none the less, an equivalent 0.08uV signal stood out more on the Degen than either of the Kenwoods. As the frequency climbed, the Kenwoods started to match and overtook the Degen. By 28 MHz, the Kenwood TS2000 was winning, with the TS430 only about 1 or 2dB behind, and the Degen a further 3dB behind that (sorry, the sig-gen is calibrated in dBm only so its easier for me to talk dBm rather than uV). All my testing was carried out using SSB modes.
And what about the AM BCB? Normally ham radios are hog-tied in this area of the spectrum with some extra fixed attenuation, but both ham rigs here had this fixed attenauation removed for DXing in this band. Even so, would they still be decently sensitive? Answer: yes! The TS430 really shone here, with even a -130dBm signal - the lowest this sig-gen will go - it was still quite plainly audible. So lets call this result -133dBm for the TS430. The TS2000 needed about -128 dBm to only just be audible, and the Degen needed -126dBm to be heard. A mixed bag of results there.

But in general, the little Degen was within a few dB of the big rigs across the spectrum. Of course in a real world test away from the bench, the Kenwoods would be all over the Degen in terms of selectivity, being able to handle a large antenna, compression point etc. And thats even before the interference fighting features of teh Kenwoods come in to play. But in a low noise environment, with a short wire antenna, the Degen wouldn't embarrass itself compared to other rigs costing twenty times as much.
Hi mitaux8030

You perfectly nailed what my doubt was.

I know the IC-R8500 is a pro receiver and in fact its selectivity is gonna be much better than that of De1103.
Nevertheless in terms of sensitivity they almost at the same level and also your comparison with the TS2000 tells us that ;-)

Note that at radioscanner.ru they measured for the De1103 a sensitivity of ~0.3 microvolts at SSB at 7 MHz.

The IC-R8500 has ~0.2 microvolts in the 2-28 MHz range.
So it's not so different. I'm convinced that the listening experience is gonna be way better than the little cheap Degen but if you feed the IC-R8500 with a Whip I was curious to know how it could compare with a De1103.

At this point I think that the De1103 would not miss too many stations with respect to the big rig.

Thanks for your contribution ;-)

73s
Marco
 

Token

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Hmmm…I was going to stay out of this thread…but I guess not. ;)

I own both radios in question, the DE1103 and the R8500. And I have done side-by-side comparisons of the DE1103 (and other portables) to several of my desktops, including the R8500 (the R8500 is not, by the way, an exceptionally good HF radio, but it is one of the better ones made that includes the HF ability with the VHF/UHF ability). The basic answer I have found is that on a small to moderate sized external antenna the good portables will hear almost every signal the desktops will on the same antenna as long as those signals are in the clear and there is little interference. However, if you have the room for a large or full sized HF antenna, or the signal is in a crowded or high noise environment, the desktop will pull out signals the DE1103 turns to mush.

What it comes down to, in my opinion and from my first hand experience, is if you are listening to AM mode broadcast stations with mid to high power output and have a mid sized to small external antenna the better portables are going to do just about as well as the desktops. But, if you have a large or a very efficient antenna that provides higher received signal levels the desktop will handle the situation better (less likely to overload/image), resulting in hearing very weak stations the portable will never hear on the smaller antennas or be able to handle because of their response to the larger antennas. Additionally, if your reception targets are lower power broadcast stations, non-broadcast stations in other than AM mode, or in very crowded portions of the spectrum, (i.e. for everything but arm chair copy broadcast) the desktop generally performs better than the portable regardless of antenna (down to a very small antenna size, like say a whip).

To reiterate, if your only measurement of success is raw sensitivity and you ignore all of the other important receiver performance factors (like dynamic range, image rejection, close signal rejection, filter performance, etc, etc) then the portables like the Degen DE1103 are not that bad. Their raw sensitivity is typically on the order of many desktops, possibly exceeding some desktops in some regions. But, raw sensitivity is never the only answer, so everything else HAS to be considered.

I have measured the sensitivity of the DE1103 and also of the R8500. At 10 MHz using the SSB filter width achieving a 10 dB SINAD I got about 0.32 microVolt (-117 dBm) for the DE1103 and about 0.12 microVolt (-125 dBm) for the R8500 (most unbiased 3rd party measurements result in better numbers than the Icom published 0.2 microVolt from 2-28 MHz). AM mode at the same freq I got about 1.1 microVolt (-106 dBm) for the DE1103 and about 1.4 microVolt (-104 dBm) for the R8500.

As for MDS and audio receivers (by the way, I have measured the R8500 at about -133-135 dBm MDS). Yes, this is a number that is good to know (and quick and easy to measure) but has relatively little to do with overall performance, mostly because of what it does not tell you. For example, if I have an RX with an excellent MDS of -147 dBm but the filters and product detector are cut rate I could end up with a sensitivity for a usable signal (decent signal to noise ratio) that was very bad. Or if the dynamic range is poor I could end up clipping/saturating on mid level signals.

Bottom line, try the two radios side by side and on the same good, efficient, HF antenna, go for reception of things other than the big broadcasters or weaker signals completely in the clear. And you will see that the R8500 regularly outperforms the DE1103, or pretty much any recently made portable I personally have tried. In other words, yes, the DE1103 does miss a lot of signals when compared to the big rig. But, the comparison is unfair. Now try the R8500 with a short (say 36”) whip antenna and a 12 VDC battery all in your backpack as you climb to the top of a hill. Not only will the DE1103 be more fun to use and carry, but I bet it will even work every bit as well as the R8500, if not better. Errr…unless you want to listen to UHF Mil Air, or public service VHF/UHF, or VHF civ air, or hams on 6 meter, 2 meter, 70 cm, etc, etc, etc…then I guess you are out of luck with the DE1103.

The two are not even apples and oranges…it is more like apples and lizards, and each has its niche to fill.

T!
 
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nanZor

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Don't write off the Degen quite yet. If you connect a big longwire, the R8500 is going to win, no question. The 1103 will overload, squirm and complain with so much signal. But if you're only using a little short wire antenna, lets say 10 feet long, then perhaps the Degen has an equal chance of pulling even.
A side note about the Degen 1103 - it runs the TA2057 chip, and the AM/SSB output from pin #18 on a limited number of early units appears to be easily overloaded much faster than the front end rf amp. Kiwa provides a network resistor change mod for those early units and can identify for sure if it would benefit from it. I enjoyed reading your writeup / testing from some 2009 threads. Great stuff.

I'm running into the same issue for the Grundig 750 / Tecsun S2000 which uses the same chip, and a bunch of us are directly attenuating the IF output from the chip on pin 18 to give us some more headroom - beyond just properly operating the attenuator / rf gain control which does not fully solve the issue without the mod.

In this case, less IF gain is more! :)
 
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