My IC 7700 Meets a K3 ( Update # 2) July-2011

Jeff VE1ZAC

I have been planning to buy a second transceiver for a while. Why ? No particular reason other than I want * another one. Plus, I love doing comparisons. I really like the 7700 and have no complaints ( well a few complaints) and I have an Icom 706 with good CW filters for mobile use. Let’s face it, the 7700 is the antichrist of mobile rigs. When you get it to your desk top, it’s staying there through anything.. even earthquakes. So, let’s say I want a rig in between.. a competitive rig for mobile use with , umm…and some…uh.. oh, the heck with it. I just wanted to see what all the K3 fuss was about ! ( see * above) I admit it.

(If there is a chapter of “Transceivers Anonymous” around here, I might join up)

My K3,Serial # 6000984746554 (.... oh wait, that was for a commemorative model fire engine from the Franklin mint) comes with "Cult" status, apparently, and now that I have had one for a month+ and have done some serious listening and side by side comparing to the 7700, I am prepared to make a comparison. ( Seriously, I have NOT memorized the serial number.. shocking, I know)

But first, a list of article caveats:

1. This will NOT be another gushing cult article, for either rig. ‘I tells it likes I sees it’.
2. This comparison is coloured by CW contest and CW DXing needs, primarily. I rarely use SSB and can’t speak to SSB features. I do like to tune around the bands and listen to stuff as well, but not often.
3. I am going to assume the reader is a person that has, essentially, good hearing. By this, I mean able to hear tones up to 10 kHz in both ears, and both ears have thresholds at frequencies up to 10KHz that are within .5 dB of each other. In other words, normal 50 year old male hearing.
4. I assume you understand from the preamble, that if you start foaming at the mouth because you think I am slagging either rig, my apologies and don't send me your complaints. Buy your own rigs and write your own article. It’s a free country, that way.

Right,  the executive summary: The IC7700 is a better rig, but the K3 has some features worthy of note. They aren’t exactly the “Same”.

So.. this is a users tale of owning and operating two of the reputed ‘pretty darned good transceivers’ available to hams who want to spend the money on them. And that seems to be lots of folks, and lots of money, for both rigs.

Picture first:

There it is, sidled up to the port side of the 7700. The thing on top is a phase control unit for a Misek style MicroSWA antenna… in fact, the bulk of the little boxes under or on the rigs are involved with a multitude of receive only antennas and a compensated splitter. I rigged up a switch to make it easy to switch antennas between rigs for fast signal comparisons. Software is Dave Bernstein’s ( St. Bernstein) DX Lab Suite and the little panorama display on the monitor is SpectraVue from RF Space and MoeTronics, used with an SDR-IQ plugged into the IF port on the K3. Hiding behind the laptop is a 600 watt homebrew QSK amp. (Not used during these tests). The VFO control for the panorama display can work direct to the K3 or indirect via DX Lab Commander. More on this in the write up. The speaker thingy on top of the 7700 is a Centrios bookshelf speaker with tweeter removed and 2 LP and 2 HP passive filters installed… it walks and talks like an SP20 speaker/filter combo. I used that with both rigs for audio tests.

I also made a lot of effort to set both rigs up with comparable functions, especially AGC and filtering when comparing them during on the air tests. The comparison items are items that I think warrant attention. Assume everything else is fine, or I am not terribly interested in it.

User qualifications: I am not just another handsome face, despite appearances. I am technically competent and can absorb any of the engineering involved with transceiver design features… so let’s just say I don’t have anything in the “mystery box”, except why some designers skip certain things or leave out important items. I have one big item like that for each of the transceivers. I work CW 95% ( the other 5% is involuntary dozing) , do some contesting and a lot of DX hunting.

The summary chart:

Side by Side comparison of IC7700 and Elecraft K3
11/1/2010 Check means "Winner"
Item	7700	K3	Note	7700 Points	K3 Points
Light Weight		√		0	5
Interconnect complexity	√			5	3
Full interconnects	√	√		5	5
Service	√	√		3	3
Manual	√			5	3
Power out	√			5	2
Sound quality	√			5	3
VFO operations	√			5	2
NB		√		3	5
NR	√			5	2
Taylored filter functions	√	√		5	5
Close in CW contesting	√	√	1	5	4.5
SWLing	√			5	0
Panel ergonomics	√			5	2
Front Panel Display	√			5	1
Narrow filter ringing	√			5	2
Extra functions		√		4	5
Band stacking	√			5	0
Memo pad	√			5	0
Switched antenna inputs	√			4	2
Delayed RF out for amplifier		√		0	5
Rcv ant input control	√	√		5	5
Spectrum display	√	√	2	5	5
Control set features		√	3	4	5
AGC control & range	√			5	3
Mobile applications		√		0	5
IF output		√	4	0	2
			Totals:	108	84.5
Point Scoring system: (Highly Subjective)	1 to 5
Perfect	5
Viking funeral required	0
Notes:
1	I give the edge to 7700, but they are very close. Used CQWW for test
2	Requires separate computer or attachement for K3, figured in price
3	Icom does not send VFO B automatically… a major deficit. ICOM.. PAY ATTENTION !
4	Useful for spectrum display, not necessary with ext. SDR to do this function

(Almost) In order, here is the discussion:

Weight and Power: Nothing much to compare. The 7700 would stimulate a normal person to spend a little more time in the gym before attempting to move it. The K3 is a flyweight. If you are going mobile, you would appreciate the lighter box. Although, you still need a bunch of stuff that is built into the 7700, like a power supply. The 7700 will coast all day at 200 watts out. The K3 is 100 watts. Overall, when you add up all the bits to make each rig do it’s thing, and allow for the double power of the 7700, the weight isn’t that different. However, the K3 allows sensible handling of the components by us old farts.

Interconnectivity: Both rigs have a full slate of interface connections, but the 7700 wins from simplicity, if you don’t add a zillion things to the output. A basic ac plug, a computer cable, a mic or key and an antenna or two and you are in full tilt contest mode. Both allow hooking everything, including the kitchen sink, to the rig. I did discover some significant hash coming from the long USB/RS232 cable I ordered with the K3. It was raising the noise floor at low bands by 5 or 6 dB. Chokes didn’t seem to help, so I wound up pushing a new braid over the entire cable and grounding it at both ends. That solved the problem.

Service: I score them both as similar. Icom is very responsive to service needs either at their factory centers or at dealers. The 7700 is more expensive to ship, however, and the packaging and moving puts us back to that gym membership item again. The K3 can be assembled by the owner, but it’s just nuts and bolts. No real kit building. Plus, I am told that most of the K3’s are ordered assembled. So, you’re on the phone or shipping it back if you blow something up. You might be in better shape with module replacement on your own with the K3 although the 7700 follows the normal Icom methods of late and the chassis is very decent to work on. I have been inside mine a few times. It’s big and well thought out.

Updated: A chum pointed out that a K3 owner is far more likely to attempt to replace a module themselves than an IC7700 owner, to which I agree. For that reason, this item should be tipped in favour of the K3.

Manual: Icom wins. You have to see the manual; it’s a work of art. Comes in a very sturdy binder for lay flat use. The K3 manual is all there, but not as much info and you have to be aware of frequent updates. Mine claims there is a menu for adjusting the DSP filter slopes, but I have yet to find that function, for example. The Icom manual contains everything.. even a complete set of fold out schematics. It’s a publishing gold standard.

Sound Quality: Here it is, one of my K3 peeves. In the name of all that is right in the world.. what on earth was EleCraft doing when the audio chain was up for grabs ? It just isn’t good. I admit that good audio is hard to deliver, but transceiver companies do it all the time. Switching the signal back and forth between the 7700 and K3 and even the 706 on the radio desk puts the audio from the K3 right on the bottom. The first week I had the radio, I almost sent it back because of this. I would pay money for a better quality audio sound… let’s get with the picture here EleCraft.. this isn’t a cheap radio for what it delivers. Surely you can do better. The sound from the 7700 is superb. Caveat… both radios have small internal speakers that are marginal. An external bookshelf type speaker can really enhance the audio from both rigs, but the K3 never gets close to sounding “Good”. The spec’s for the K3 claim the audio THD is 10% … 10% ? How about aiming for 1% ? It can be done with some effort.

VFO Operations, Band Stacking, Memo Pad, Memory functions: Icom wins this one.. no contest. I was disappointed with the efforts on the K3 side. This isn’t mechanical stuff, just code. The VFO and memory control is clunky and seems like it was added on rather than made a prime part of the operator interface. Icom does this superbly. Each band has three pushes of a band switch which save whatever is going to a stack for that band. Every time you push the band switch you pop the top of the stack into operation. This is the way band data was meant to be used. In a contest it’s fantastic. On top of that, there is a one push memo pad that saves everything in a 5 or 10 item stack which is band independent. You don’t have to think about anything.. one push saves what your are working.

In it’s favour, K3 has a separate knob for the VFO B… all rigs should have this feature. This is kind of connected to the second receiver issue.

Second receiver: I didn’t order the second receiver for the K3 as I intended this rig to BE the second receiver for the 7700, which it does just fine. Since I don’t have it in either rig, it makes it easy to compare rigs. Both rigs make interfacing to an external receiver straightforward. Dave Bernstein’s DX Lab Commander allows setting up a second port that can control a second rig. This port can be setup in a different control language from the primary rig. In essence, it’s a control translator. Brilliant idea, and cause for nominating Dave for Sainthood. It works very well. I use a freeware virtual port emulator on my computer which makes it really easy to set up virtual share ports, splitters, port pairs, whatever you need. For example, you can setup the SDRIQ device to be controlled from the primary rig in parallel with Commander and pipe the second Commander port to run a different flavoured rig for the second receiver from VFO B. It works. Not quite as simple as a second receiver right in the radio, but just as useful for most of the second receiver tasks. The K3 has some nice functions built in for the second receiver if you get it, like diversity receive. But, you have to spend another $1000 to $1200 for the thing with a whole redundant set of roofing filters. Price adds up quick. I didn’t need this so skipped it. ( note, I now have a second receiver in my K3.. works very well, as advertised)

There is one thing the K3 does better than 7700 and involves the VFO B data commands. This warrants a section by itself.

Control Set Features: Both radios have very complete control sets. But one feature really stands out for the K3. The VFO B knob causes VFO B data commands to issue from the control port, uncalled. And, the K3 sends out commands about being split. This feature is NOT AVAILABLE IN THE ICOM! Good grief, what is with these folks at Icom? This feature alone would cause the DX and contest community to raise their  arms and shout for joy, and likely cause a run on 7700’s for the next 2 years. It’s just a simple bit of code to push out with the next revision. Do they not realize how useful that will be to controlling a second rig on VFO B ? It must be a conspiracy. Come on Icom, let’s get with the user needs here. This is a real deficiency of the 7700. Please tell the world about split and which VFO the data is coming from.

Note.. BIG TIME note !: in Firmware version 1.21, Icom now allows external information about split. Dave Bernstein has absorbed it into his excellent Commander... So, maybe writing reviews like this really helps ? Who knows.   So.... what do we have to do to get the external VFO B function engaged by Icom ?

NB: The K3 wins. The Icom NB is very good and has a front panel dedicated knob, but the K3 NB 2 stage system is awesome. I think it could handle the national debt if it was tasked. This is the new gold standard. It requires lots of fine tuning per band/ application, but it is capable of winkling out the worst kind of power line noise I am subjected to daily, so it gets my vote.

NR: Icom wins this one. The Icom DSP engineering for this auto correlation function is superb. A dedicated panel adjustment, and it is very hard to get it to distort anything. It works superbly. The K3 is fussy and never seems to really get in gear. There is adjustment available but it’s obvious the designers see this as a secondary feature. Wrong. You have to sit in front of both rigs to see what a treat this feature can be to listening to any kind of signal in crappy conditions.

I admit, this might be 'psycho acoustics- 101', but it's real and affects listening.

Filter Functions: The 7700 uses a set of roofing filters in the first (VHF) IF that go to 3KHz. After that, the conversion system spews everything into an IF of 50 KHz where all other functions take place in the world of DSP.. including the filters. Filters are totally software. The K3 uses a 1^st IF of 9 MHz allowing the use of 8 pole InRad and other 9MHz crystal filters as roofing types. The rest of the filtering takes place at a very low IF frequency in software. Both systems work very well. There is a lot of press about the dynamic range resulting from the filter systems and the K3 has a reportedly high dynamic range. What does this mean? To most of us, it determines how well we can copy a weak signal when it is located very close to a very loud signal without desensitizing the receivers AGC system or having RF from the strong signal bleeding through the lower part of the filter skirts.

I have been listening to every close in loud and weak signal I could find in last few weeks for tests. Co-incidentally, CQWW CW was on this weekend.. the perfect testing opportunity. I spent hours repeating the tests on high and low bands, various antennas and various filter widths. In all cases I matched the AGC speed and filter bandwidth, as well as the signal strengths of the signal at the receiver input. What did I find? Well, this is where it gets interesting. I expected the K3 to have drastically better close in operation than the 7700. Did I see that? Nope. That’s right… it was not possible to detect a difference. In fact, it seemed 'slightly' better with the 7700. I would rank them equal but there was one difference. I left the APF filter on in the 7700 and it isn’t implemented yet in my K3. ( It is now) It’s possible that might make a little difference, but not that much. APF means Audio Peak Filter. ( Since writing the original, I have the Beta version of APF in place, it isn't as good as the APF function in the 7700, but it does help in some situations.. again, I don't like the sound of the signal.)

Even with the filters dialled down to 150 Hz, I noticed a slight increase in the span required to get away from the big signal on the K3. Note, I AM saying that both of these receivers are very good. But I expected some black and white performance from the K3. It wasn’t there. If the K3 is considered such a great CW receiver, my claim is that the 7700 is just as good.

I left the skirts on the 7700 in the soft position. Apparently the K3’s are defaulted to soft, and I can’t find the menu pick suggested in the manual to make them steeper yet. ( Since discovered, it's for very narrow filter widths) I will continue to sort that problem out, but even at the soft mode, they were both very very good. Remember, this is direct switching of antenna to same signal, same setup on the other transceiver. A very dynamic and useful test.

SWLing: Not much to write about here, the K3 is close to useless for this function, to my mind. The 7700 excels. Important to some, not to others. If I had to take one mobile for portable use, that wasn’t just a contest, I would even pick my 706 over the K3 for this reason.

(Note: the K3 would probably be  OK for SWLing with the 6 KHz AM filter installed... I didn't get one )

Panel Ergonomics: Again, not much of a contest. The 7700 has a superbly designed panel and display designed for the operator. The K3 isn’t. End of story. I like a radio with a good panel design.

Front Panel Display: Again, no contest. The colour LCD panel on the 7700 allows very comfortable use without a computer, including the spectrum display. The K3, to my mind becomes a very plain machine without a computer and/or an external spectrum display.

Narrow filter ringing: I can get rid of ringing on the narrowest filter widths on the 7700.. I struggled mightily with this on the K3. The 7700 sounds better. Sorry, it does, and I invite my local ham friends to drop in an listen. Note the caveat about hearing at the top of this article.

Extra Functions: The K3 has some cute extra functions. They don’t really contribute to performance much, but they make all kinds of things easy to do. The 7700 also has a bunch of extra things built in, like RTTY and PSK with waterfall display on the LCD panel… it could be a tie, but I gave the edge to the K3 because of the novelty of some of the functions, like the audio effects on the headphone jack.

Switched Antenna Inputs: 4 on the 7700 plus the receive port, 2 on the K3 plus receive port. The 4 on the 7700 make it very easy to utilize a bunch of different antennas. A feature I didn’t think was important when I got the radio, but have grown to depend on.

Delayed RF Out: The K3 has an adjustable RF delay for amplifier use. This is highly sane design, something not present in the 7700 and can lead to some nasty surprises when used with slow switching external amplifiers. Another thing that Icom needs to get on with. If you do use an external amp with the 7700, be darn sure your switching business is taken care of within 10 mS, or you might be doing hot switching.. bad news all around.

Receive Antenna Control: Excellent on both rigs. This is stored with band data. Kudos to both companies, but Icom makes this a stock feature. Even if you don’t have room for a beverage, you probably do have room for a Pennant or a K9AY. One of these with a receive port will change the way you work on low bands.

Spectrum Display: Icom wins.. a beautiful display on front panel. Outboard gear on the K3, but both rigs benefit from an external application that shows spectrum display with waterfall. You begin to wonder how you ever worked without it. A nice feature of the 7700 is that you can run very prettily without an external computer. You don't sacrifice the spectrum display.

AGC Control and Range: One of my friends continually rides his RF gain control with the AGC turned off. After having my own K3 here for a while, I see why he does it. There are a lot of situations where this seems the only way to sort stuff out. A side effect of doing this ? The NB and NR functions are connected to the AGC in performance. If you turn the AGC right off, these functions don’t seem to work as well. Icom wins.. fabulous AGC control and response throughout the full RF range. I usually leave the AGC response on variable on a front panel control, but seldom change it off fast. My ‘hearing’ thanks Icom.

The Point Scoring System: I came up with a way to assign some subjective points to the receivers in these categories. Highly subjective, based on my feel and use. Five means it would be hard to improve it. One means it has a little redeeming value. If there is a zero.. I think it should have a Viking funeral.

Price: Everyone is dying to hear what I have to say here, I bet. My K3 with the stuff I ordered, all filter slots full, no second receiver, and allowing for pan adapter, power supply, etc, comes within $1500 to $2000 of the IC 7700. The 7700 has no options.. it’s the full meal deal. Am I being fussy about some of these features ? You bet ! For the money invested in these radios, you should be fussy. You can still buy a pretty good used car for what these things cost.

When looking at the K3 deficiencies, there are two conclusions, both valid, depending on the user.

1. The K3 is not cheap, and approaches the performance of the 7700. But at $1500 to $2000 less, it might be worth sacrificing the many improved  7700 features.

2. The 7700 has increased performance and features, making it well worth the extra $1500 to $2000.

For me, I am firmly in the “B” camp. Enjoy !