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Author Topic: KX3 / Sherwood Engineering Inc.  (Read 42610 times)
OH6I
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« on: August 11, 2012, 12:14:28 AM »

Nice numbers for KX3  Smiley
http://www.sherweng.com/table.html

Jari
OH6I
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KE5JPP
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« Reply #1 on: August 11, 2012, 05:38:38 AM »

Nice numbers for KX3  Smiley
http://www.sherweng.com/table.html

Jari
OH6I

Armchair specmanship again.  Now you got a bunch of appliance operators all starry eyed over the KX3 even though the Sherwood tables mean very little in how those rigs are to operate in real world circumstances.  The numbers are OK if you plan on using the KX3 on the test bench hooked to a bunch of expensive test equipment.   Roll Eyes

Gene
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AE7UT
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« Reply #2 on: August 11, 2012, 09:09:01 AM »

Yea..... What the heck were you thinking when you bought that POS?
Send it to me ASAP and I'll dispose of it properly.   Grin

73. Green with envy!
Stan AE7UT
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KB1GMX
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« Reply #3 on: August 11, 2012, 01:07:17 PM »

Those numbers are one of the tools we have to compare radios in a non-subjective way.

Still I'd agree a listening test is needed as I've played with a few out there that had great number but
the general sound grated on my nerves after 20 min of listening due to things like high background
hiss, distortion in the audio or DSP artifacts.

I've looked at the KX3 and I'm not a convert but I see it as having portability
and performance that only a few radios match (thinking ft817, and IC703).

Also there are radios near the bottom that really belong there!


Allison
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ZENKI
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« Reply #4 on: August 11, 2012, 05:49:46 PM »

I agree. Receiver performance that will  hardly needed for the intended role of the radio. Your KX3 or any radio  for that matter wont be overloading by using a wire up the tree for the antenna, or by using any low efficiency portable antenna.

While it is great that Elecraft has worked hard to design an excellent receiver in the KX3, most of is potential will be squandered because numbers  above the minimum receiver dynamic  requirements will be wasted More aint better.
You really also need to look at all other important receiver performance numbers before jumping to the automatic conclusion that its better than anything else. I would like to see the reciprocal mixing dynamic range numbers as well
as the inband IMD numbers. The K3 is radio for example that has very poor inband RX IMD despite its great receiver numbers. When you  use a clean sounding direct sampling SDR radios you  soon realize  how important
low distortion and low IMD is for comfortable listening.  The KX3 does have impressive phase noise numbers which should help things.

Another point is that because of the receiver architecture, the KX3 receiver performance will be worst and fall apart  at close signals spacings. This is  because of the opposite sideband rejection. I bet everyone who said it was the best because it was on the top of the list forgot to read the Sherwoods footnotes! The K3 and the FT5000 will still be better in this regard.

While these receiver numbers for the KX3 are very good it will have unfortunate consequences. The radio will be popular and many hams will now go out and buy this radio because of its supposed good receiver. The problem is
that its a 10 watt radio. Whats now going to happen is that all the hams who own this radio are going to probably buy some cheap CB bipolar 12 volt PA and use  this radio on the air to the detriment of all other hams who also also got equally good receivers and probably cleaner transmitters.

The transmitter IMD performance of the KX3 will be poor because its a portable battery operated radio. I seriously doubt that Elecraft set out to make the transmitter in the KX3 as good as its receiver performance.  This is essentially the point that most hams miss. Its impossible to realize  and use all the excellent receiver numbers of the KX3 on the air today because hams transmitters on the air have such poor performance. Here we talking about key clicks, phase noise and IMD and splatter transients. It does not matter how good your receiver is, its useless if other peoples transmitters are jamming your receiver with crud that cant be removed. Would it not be smarter spending money and research on delivering  better transmitters than endless 1 up-manship marketing games for better receiver performance on a list?

The KX3 potential is squandered  because it will have a cheap and nasty PA producing a lot IMD, despite its excellent phase noise numbers. I could have used the KX3 to drive a small clean 4cx350F tetrode amplifier producing a clean signal if the transmitter IMD performance was excellent to start off with.  So for those who dont operate from a picnic table the opportunity is lost to use use its excellent receiver performance from the home station. There will be those ignorant CB type hams who dont care and have a poor understanding of this subject matter who will forge ahead and use any crap CB amplifier with this radio and brag how good it is . Ignorance is bliss.

Elecraft is not alone with this kind of stupidity. The HPSDR crew are on the same path. Dazzling receiver and transmitter IMD performance and then they offer a cheap 12 volt bipolar amp with crap IMD performance.
Good thinking Batman!

Since the receiver performance is so good Elecraft should offer a different option for those who want to use the radio from their home stations. They should offer a 200 watt high voltage fet amplifier that can deliver 200 watts and decent IMD performance.  VRF148's driving VRF151E's would be the way to go. These  kind PA devices will deliver transmitter performance that will match the KX3's  good receiver performance. This wont happen, so the KX3 will just be another blah blah radio that offers very little else except for a position on hypothetical chart that has little meaning in real life.

KX3=0 because its transmitter  will be crap like the K3 with poor IMD performance. If you produced a chart based solely on transmitter performance most of the radios on the top of Sherwoods list would be ranked the poorest, and that says it all. We really need to wake-up to this marketing hype that over emphasizes receiver performance over everything else as the main driver of on air success.  On air success is not a 1 variable equation that only relies on receiver performance.

The KX3  will be popular, like owning a samurai sword, you can pretend you going to cut through the QRM with your super receiver and win the battle like a samurai warrior. Then Johny Rotten Splatter comes along and ruins your dreams. Life sucks  if your ignore the laws of physics! The KX3 does not have a inband IMD splatter blanker so nothing is going to save your excellent receiver.

Excuse me, I need to go down the road on the Autobahn  at 125mph in my European designed car, a car designed for the real world whose performance can be used. Lifes good in my driving world. Excellent car and no technical
limitations! When will ham manufacturers  get a reality check?

When will the K4 be released?  maybe that will be THE perfect design.


 




Nice numbers for KX3  Smiley
http://www.sherweng.com/table.html

Jari
OH6I

Armchair specmanship again.  Now you got a bunch of appliance operators all starry eyed over the KX3 even though the Sherwood tables mean very little in how those rigs are to operate in real world circumstances.  The numbers are OK if you plan on using the KX3 on the test bench hooked to a bunch of expensive test equipment.   Roll Eyes

Gene
« Last Edit: August 11, 2012, 05:56:25 PM by ZENKI » Logged
LA9XSA
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« Reply #5 on: August 12, 2012, 05:08:54 PM »

ZENKI, your previous opinion was that the KX-3 would be a poor radio with a far too good receiver, because it was 10 watts instead of 20 watts, but that 20 watts was enough for everyone. Further, that a QRP radio would have no use for narrow filters. Now you're assuming that people who can afford a KX-3 would connect it to horrible illegal non-linear CB amplifiers instead of getting a decent amateur quality amplifier.

It also puzzles me why you think Elecraft should deliver a 200 watt radio when you don't trust them to build a 100 watt amplifier or a 10 watt radio that's up to spec.

The one thing you're right about is that you can't easily filter out wide band splatter with receiver notching filters - that's because it's superimposed on the signal. Due to its random (non-periodic) nature, it's also hard for any noise blanker or DSP to deal with. That's something you deal with by having antennas with nulls, phasing networks, or by identifying the culprit and convincing him to fix his rig, first by asking politely and then by reporting him.

You don't like the KX-3, but the reasons why seem to evolve.
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ZENKI
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« Reply #6 on: August 13, 2012, 03:14:08 AM »

You should take time and study the receiver architecture before making claims about roofing  filters and how they work. The KX3 because of its receiver architecture will have its performance handicapped because of the opposite sideband suppression that will prevent you obtaining fantastic blocking numbers below 1khz spacing! So yes narrow roofing filters wont do you much good when the receiver is QRM'ing itself! When will people actually understand what roofing filters actually do in the context of the receiver architecture usesd?

You tell me where in the world you going to use such an excellent receiver with a wire strung up in tree running pileups all day long? Do you think 10 watts is enough power to keep your frequency? You seem to have grand delusions
that some radio with an impressive receiver  and 10 watts is going to give you mythical powers on crowded band conditions with a wire strung up a tree. Get real!

The comments I made  will be proven correct, 10 watts is not very effective for working DX. Its a power output that  makes you struggle. 20 watts is a more realistic power output and is  only 6.9 db down from 100 watts. 10 watts is 10db down and you cant in wildest dreams build a 4db gain antenna when operating from a picnic table. You really need a dose of reality salts!

I have done the experiment 1000's of times on many paths. Most people would not even comment when you reduce your power from 100 watts down to 20 or 25 watts, they certainly notice when you drop your power down to the 10 watt level.  These results do vary because difference receivers have different AGC parameters which produces different results for each receiving operator. Point Is more is better and 20 watts for SSB is a  perfect power level for portable operation. Ask any  SGC2020 owner or for that matter ask someone who uses Mil Manpack with a VOGAD speech processor. We will just have to disagree on this point  let it be.

Why should it puzzle you that 200 watt PA  should be produced? Its perfectly logical way of broadening the market appeal of the KX3. Since the KX3 has a receiver that would perform admirably  in a home station using big antennas why not  produce a integration kit that will make it a full base station radio. Remember the Atlas 210X or 215. That radio had a console that you could plug the Atlas into making a nice combination mobile or home station radio. Why cant this be a option for the KX3? You going to spend 1000 dollars on a radio with a receiver that can deliver better performance than the IC7800 and IC7700 and let it lay at the bottom of your draw like a 2 meter HT?  If you were sensible you would use the KX3 because it probably performs better than the radio you now own! Who knows Elecraft might spin the KX3 into a cheap fixed station radio.

The point is that a KX3 with 200 watt PA makes a nice holiday  DXpedition  or mobile radio. The Kenwood TS480HX is popular for this reason, it can be remoted and you dont need  an expensive marginal 500 watt amp because 200 watts is more than enough. Its also the convenience and cost factors of installing big amps and batteries. A 200 watt clean FET amp would be nice for home station use. You at least then would have  a great receiver and a equally great performing transmitters thats not a piece  CB IMD producing POS. Its simple, why is the logic so hard to follow? Do some lateral thinking for Elecraft, it might help their bottom line, you seem to be a Aptos Koolaid drinker.

My comments are spot on about hams using CB amps, because thats exactly whats going to happen.  The new Ten Tec amplifier is the most expensive amplifier on the market. It delivers 1 watt at the cost of $7.80 per watt. The KPA500 is also an expensive way of delivering 1 watt per dollar spent. The Ameritron ALS500 is the cheapest at $1.56 per watt. The point is that hams are cheap and wont spend excessive amounts of money on  expensive amplifiers. The FT817 is a perfect example, most are using CB amps with a radio that has crummy IMD performance. If you hear all these crap FT817's on the air with their crap CB amplifiers you would be worried too.

Well my thinking will evolve as the product is evolved and released. There is a  huge backlog and many unhappy users who are not happy with the firmware and final finish of the radio. Why should my opinion or anyone elses opinions be engraved in rock. The K3 has evolved over  the years and has become better as a result of testing and criticisms by users. If  it was not for these criticisms by the users we would  have a highly overrated crap radio. My view is that If thinking critically about any product is the best way of making sure we get better products. For 30 years ham just shut their mouths and took year after years of the sameness with no real improvements in receivers and transmitters

If it was not for the likes of ON4UN, Rohde, W8JI and Sherwood amongst others our receivers today would be no better than the average 20 dollar CB radio. So rather than being endless argumentative think laterally and make some suggestions. Besides this is an forum for open discussion, if you just want to Endlessy praise your favorite brand you can go to the Elecraft reflector, they appreciate people who are drunk on the Koolaid. Dissenting from conformists opinions is not welcome on this reflector and doing so invites the wrathr of the Elecraft mafia.

Anyway its early days so far for the KX3 and its selling like hotcakes, everyone makes up their own mind at the end of the day and thats how it should be.  Look at the FT817 a crap radio in all aspects of performance and its probably the most popular ham radio transceiver invented. I doubt criticism by me or anyone else would have changed the marketing success of the  FT817. The same goes for the KX3 it will stand on its on merits.  Great receiver shame about the transmitter, nufff said.



.







ZENKI, your previous opinion was that the KX-3 would be a poor radio with a far too good receiver, because it was 10 watts instead of 20 watts, but that 20 watts was enough for everyone. Further, that a QRP radio would have no use for narrow filters. Now you're assuming that people who can afford a KX-3 would connect it to horrible illegal non-linear CB amplifiers instead of getting a decent amateur quality amplifier.

It also puzzles me why you think Elecraft should deliver a 200 watt radio when you don't trust them to build a 100 watt amplifier or a 10 watt radio that's up to spec.

The one thing you're right about is that you can't easily filter out wide band splatter with receiver notching filters - that's because it's superimposed on the signal. Due to its random (non-periodic) nature, it's also hard for any noise blanker or DSP to deal with. That's something you deal with by having antennas with nulls, phasing networks, or by identifying the culprit and convincing him to fix his rig, first by asking politely and then by reporting him.

You don't like the KX-3, but the reasons why seem to evolve.
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NI0Z
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« Reply #7 on: August 13, 2012, 08:43:06 AM »

I have seen a few DXexpeditions take HEX beams along because they can be packed up fairly nicely.  I am guessing that on an antenna like that the specs can be leveraged nicely.  I will actually know in the future when I test it out on my roof mounted hex.

If the radio were really expensive I would agree that it's merits might be squandered, however, at $1K and the band coverage it possesses, there's nothing wrong with owning a radio like this for portable operations.  It's like the Swiss army knife of ham radios almost.  It's a tool like any other radio, so radio wars are pointless in my mind.

Isnt it kinda of funny to argue a radio is too good so therefore it must be bad?  I am not making fun of anyone, it's just a question I am asking?

Ironically most of its use for me will be on my base station trying out QRP and Digital coms on the HEX.  BTW, the hex beams at about $700 delivered are 1 heck of a value.  It would be nice to see someone make one even more portable for expeditions and field use.

I guess my point is that I have seen many people talk about portable Setups that cost far more than the KX3, so it's really not a strong argument in my humble opinion to say the KX3's merits will be squandered.  

I will say more when I have actually put it to the test though, and so I will admit, I could be all wrong about the thing.  

Time will tell for me.
« Last Edit: August 13, 2012, 09:02:11 AM by NI0Z » Logged

STAYVERTICAL
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« Reply #8 on: August 13, 2012, 05:20:04 PM »

The day I realised there was more that I did not know, than did - I stopped worrying about the minute details of life.

The KX3 looks like a great little radio, and the price seems good to me as well.
With discounting in the future it should be a real contender in the lower price category.
Not being an Engineer, I leave that high tech stuff to the experts - who can duke it out.

What I want to know is:

Does it come with interchangeable color panels? , and can you run angry birds on it?

But seriously, it seems like a really nice little QRP radio.

73 - Rob
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ZENKI
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« Reply #9 on: August 14, 2012, 03:18:10 AM »

Theres nothing basically wrong with the radio, its performance has been measured and acknowledged.
Its just that people sit here and imagine  all sorts of imaginary scenarios that are totally unrealistic for a portable radio operating on batteries.
Its gets worst when you using a wire up the tree or loaded short vertical. Do people ever estimate what their effective ERP is, or what gain  they have at low takeoff angles etc etc.
They then go onto imagine that using  such inefficient small antennas requires that your receiver is going to need chart topping receiving numbers.
The problem is not the received signal strength  its going to be  the transmitter signal level from inefficient antennas and low power.
Some might prefer to have 20 db of receiver numbers you cant use rather  than 3db more power,  that makes more sense NOT?
I would rather have 4db of transmitter gain than 30db of receiver performance that cannot be used on todays bands.

You have glowing receiver performance from the KX3 that can  never be realized simply because other peoples transmitters are so dirty. Then  people start speaking like receiver numbers are going to cut through and eliminate
all this interference that you typically encounter on the bands. A healthy reality check is in order for all this hyped up expectations.

Nobody is denying that you not going to have fun playing the QRP game with a battery operated radio. It indeed is a thrill catching a big  200 pound fish on 1lb line, but we all know the line  will break most of the time. QRP is no different you can get lucky, but its better just to use the power required to do the job properly. 25 watts from a portable operation does it every time without struggling.

The KX3 has a lot of potential regardless of which way you look at the radio. Some people just need to be realistic about their expectations and open their minds to the flexibility that this rig can offer. The KX3 with the right accessories
could be a swiss army knife radio that could be all things to all people. I just dont approve  of poor operating practices like using crap CB amplifiers  to boost its power output. Most FT817 users have done this because lefts face it 5 watts stinks on modes other than CW and digital.

 A receiver that is as good as the KX3 needs a clean amplifier that matches its receiver performance. All my Elecraft products K2 and K3 have sub standard  transmitter performance. I  wont hold my breath expecting the Elecraft will excel in producing radios or amplifiers that are much better than the average CB amplifier. Their prices are already above market average, for that price penalty you expect something for your  money not just receiver marketing hype.

Yeah I know I can build own amp if I am  unhappy, but thats not the point of the matter. The problem is that  all hams transceivers have substandard transmitters and bragging about receiver performance  all the time accomplishes very little. Besides its just plain stupid when  everyone knows that the excessive receiver performance is largely a wasted design effort. It would be nice if some design effort is directed to help alleviate these problems on the ham bands and in some time in the future we can actually all start enjoy using all this wonderful receiver numbers.

I also like extolling the virtues of such a good receiver and what  the KX3 could become. It does not have to be only a battery operated 10 watt radio. It would be nice having a compact 100 watt or 200 watt station. The Ten Tec Eagle is a good example, a real shame its transmitter has such poor TX IMD performance otherwise I would own one.

I dont ever imagine myself buying a KX3 and Elecrafts KX3 100 watt amplifier its just too messy. If I wanted a compact 100 watt radio I would buy a FT857 and no messy external amplifier. If Elecraft produced a 25 or 30 watt version all in one box I will  look at it. As far as I read it, I see no good reason to carry a super high performance receiver  and then choosing it over any other similarly equipped QRP radio with a lesser receiver. I prefer extra  power on TX.  How is it really going to make QRP operation better, easier or more enjoyable just having technical numbers that means so little in real  life?  Battery life, more TX power and a ATU that tunes anything makes more sense that just relying on receiver numbers. Another area to consider is the weather toughness of the unit, can you drop it in a mud puddle and not kill it? I would prefer to have a IP rated radio than big receiver numbers. I can just see all the spin off products  for the KX3 that will released onto the market. There will be amps, cases, waterproofing,  rugged kits and all sorts of accessories to make it a better product.  Something like a Mil Manpack configuration  thats totally robust and self contained would have been more appealing in my eyes. Maybe Yaesu will release a rugged HF manpack version of the FT817  with a 25 watt PA. They already have a excellent HF manpack radio. They just need to release  HAM friend version.


Anyway good luck to Elecraft and the KX3, its certainly a innovative radio.


I have seen a few DXexpeditions take HEX beams along because they can be packed up fairly nicely.  I am guessing that on an antenna like that the specs can be leveraged nicely.  I will actually know in the future when I test it out on my roof mounted hex.

If the radio were really expensive I would agree that it's merits might be squandered, however, at $1K and the band coverage it possesses, there's nothing wrong with owning a radio like this for portable operations.  It's like the Swiss army knife of ham radios almost.  It's a tool like any other radio, so radio wars are pointless in my mind.

Isnt it kinda of funny to argue a radio is too good so therefore it must be bad?  I am not making fun of anyone, it's just a question I am asking?

Ironically most of its use for me will be on my base station trying out QRP and Digital coms on the HEX.  BTW, the hex beams at about $700 delivered are 1 heck of a value.  It would be nice to see someone make one even more portable for expeditions and field use.

I guess my point is that I have seen many people talk about portable Setups that cost far more than the KX3, so it's really not a strong argument in my humble opinion to say the KX3's merits will be squandered.  

I will say more when I have actually put it to the test though, and so I will admit, I could be all wrong about the thing.  

Time will tell for me.
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NI0Z
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« Reply #10 on: August 14, 2012, 06:18:14 AM »

You make some good points, the KX3 does not seem like a tuff tuff radio, I have held on before.  It was actually bigger than I thought it was going to be.

If I summarize what I hear you saying is that all QRP transceivers transmitters stink.  Ok, I don't really disagree with that as I believe that statement is true of pretty much most transceivers out there. Mi will probably get hollered at for that statement, however, I have made enough QSO's using a Panadaptor to see how the majority of them splatter.  In maybe 500 qso's I have seen 2 really nice tight tight signals with little splatter.  I would likely attribute that to them running maybe 2.4K filters so that their bottom skirt of the signal still fits in the 3K window.  Many skirts I see are horrible spanning over 6k of spectrum and making the spectrum around there signals unworkable for DX work for reeling in fainter stations because their skirt washes them out.

I think there's much more money out into the receivers on the rigs than there ever will be for the transmitters unless the FCC comes out with something to force it.

Face, most users worry more about being able to hear that decent DX and then having enough reach, regardless of how their signal looks to be heard by the DX.

I had a fun QSO a few weeks ago with a gentleman who had his KX3 hooked up to his base.  We ran it with and without his amp, with and without batteries.  The Smeter varied about 4-5 units across those scenarios from about S4 to S9.  His signal looked average across those scenarios.  Keep in mind this was SSB.  On batteries I could barely copy him, he was pretty much right there in my noise floor just peaking up over the surface.

I really don't care who makes it, it just looks like it will be fun to play with and fun is what this is all about for me.  I have learned now not to get serious minded with my hobbies.  It wears away the fun if one gets to a point where something they are doing for enjoyment becomes stressful.  That's why even right now after rewiring all my station on Saturday, I am not worried that I have some loose ends to clean up.  I'll just work it the next time I am in the shack. 

Same goes for chasing DX's, and working various bands.  Someone the other day suggested you couldnt be a real ham unless you worked 160.   Ok, I guess I am not a real ham... Whoopty do!  Lol

I guess I will take my over capable swiss army knife radio when it comes and go play radio by myself. Smiley.  And that's seriously why radio wars are pointless... Who really cares what I do or don't do.... Lol. And not to offend anyone, but I won't be angry or upset if you use some other radio than I would.  It's all good and what keeps the manufacturers competing for our dollars.

Good conversation going on this.

73
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STAYVERTICAL
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« Reply #11 on: August 14, 2012, 06:43:07 PM »


What you guys are saying about transmitters seems quite true - and I must admit to not having thought much about it.
I guess it has something to do with not having a feedback mechanism to gauge the transmitter performance.

We think a lot about SWR for example, because we have a meter which gives us visual feedback.
A receiver gives us audio feedback to gauge how incoming signals sound, and how selective it is.

If every transmitter had a panadaptor type of display of the outgoing signal, I think the feedback would make things very different.
I could imagine hams looking at the display and thinking that the sidebands seem pretty wide etc.
There are probably radio's out there with such displays standard, but I would imagine many manufacturers may not want to provide a stick for hams to beat them.

Perhaps it is a case of out of sight, out of mind as regards the outgoing signal.

Some good and interesting points raised by some of the posts though.

73 - Rob

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W4OP
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« Reply #12 on: August 14, 2012, 08:06:21 PM »

There is one amateur rig that has a remarkably clean TX signal- but the waiting list is always a long one:
http://www.adat.ch/index_e.html

Still, it's nice to see so much creativity in one rig.

Dale W4OP
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KE5JPP
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« Reply #13 on: August 15, 2012, 05:04:30 AM »

From Rob Sherwood:

"With the default zero kHz IF setup, a strong signal on CW on the opposite sideband (other side of zerobeat) will only be down 60 to 70 dB due to the limitations of the I&Q cancellation. Neither the K3 nor the FT-590S have this problem with their CW roofing filters and a more standard design. The KX3 can be set to an 8-kHz IF, much like the Flex radios, but then the image would be 16 kHz away and still a potential problem in something like CQ WW with the whole CW band segment full of very strong signals. "

More proof that making a purchasing decision based solely on number in a table is not a good idea.

Gene
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« Reply #14 on: August 15, 2012, 05:16:45 AM »

From Rob Sherwood:

"With the default zero kHz IF setup, a strong signal on CW on the opposite sideband (other side of zerobeat) will only be down 60 to 70 dB due to the limitations of the I&Q cancellation. Neither the K3 nor the FT-590S have this problem with their CW roofing filters and a more standard design. The KX3 can be set to an 8-kHz IF, much like the Flex radios, but then the image would be 16 kHz away and still a potential problem in something like CQ WW with the whole CW band segment full of very strong signals. "

More proof that making a purchasing decision based solely on number in a table is not a good idea.

Gene


So like many other things - read the fine print before signing on the dotted line.
Good point Gene.

73 - Rob
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