Sep 13, 2009

Getting the most out of your rig; the results after another 6m season

Are we satisfied yet?
Another 50Mhz Es-season has just ended and I have (again) tried several transceiver set-ups and performed modifications on my 6m HF rig. From simple upgrades to a total change of the building blocks inside my rig. All just to achieve the maximum fun factor; which is combining the best possible ergonomics with optimal HF performance. Again, this is for 6m use only .
There have been a lot of opportunities to test all different equipment and many DX QSO's have been made on 6m during marginal conditions.

Why again am I so critical about the transceiver?
Working that dx on 50MHz is just a matter of being there at the exact right moment. And depending on your antenna & QTH those openings can be from several minutes down to just a few short peak moments, especially when your QTH suffers from local noise
(see my blog from april 12th). Quick operating and an informative user interface are key here.
Sure you can make nice dx contacts with any rig on 6m. But from some years of experience, both at home and our summer dx location (HB0), I learned that some really can make a difference. At home I have a 5 element yagi @12m AGL and using 100W I managed to work >75 different countries during this summer Es season. Some were easy, others not. But the fun is in the game of the hunt right ?
Well sharpening your tools is too.

50MHz transceivers I have tested at home
Where did I end up last year?
My TS570SG received several upgrades including both 400 and 2100Hz IF crystal filters from INRAD, a temperature controlled crystal heater for the master LO and an outboard preamp from SSB Electronics.
In the end an IC746 on loan was much more fun and proved to be the master of ergonomics.

This year I tried some more HF rigs for 6m:
(note: these are my personal experiences. Please do not feel offended by my comments)

Kenwood TS570SG stage II upgrade
The whole internals of the rig have been changed through bypassing lots of circuitry like the bandfilter, attenuator, pre-amp and the complete front end stage, straight up till the 1st mixer input. See my previous blog. It was written some months after that modification was done so there was plenty of time to test and verify the results.
RX is much better but the aged 16 bit AF DSP shows its limits.
Verdict: Filter settings less than 200Hz filtering are useless due to ringing. Ergonomically this rig is OK but it sure is not an IC746.

Elecraft K2+XV50 transverter
The Analogue Reference Combo, period.
What a sound, superb RX performance. Best building kit ever in history of Hamradio offering a great deal of satisfaction. And still lots of room for personal tweaking, upgrading etc.
Verdict: Ergonomics and quick 6m operation suck big time. Like every transverter the power is only 20W, thus requires an external amplifier.

K2+XV50 +HamRadio Deluxe
Been there, tried that using a Griffon USB PowerMate as VFO knob.
Verdict: slow tuning, no progressive speed like Icom, no real VFO feel, user interface not optimal.

K2+XV50 in Master-Slave link to the TS570SG.
Using the TS570 ergonomics to tune the VFO and link the K2. This set-up even allowed for RX diversity to some extent. Dedicated software written by a friend of a friend, see my blog on april the 9th.
Verdict: K2 has drift which needs to be re-set at every start-up. Early sw version has some bugs causing laptop hang-ups and small but evident latency. There sure is room for enhancement but I never gave it a real chance because a new opportunity arrived:

Icom IC7400 (=IC746 Pro)
Suddenly there is a used IC7400 available, in mint condition and at a reasonable price. I already have owned a 7400 some years ago. It is a great second rig for HF, especially during holidays. It carries 144Mhz at 100W output too. However listening to noise and weak signals on 144Mhz from this IF DSP rig was annoying to my ears. I instantly noticed a huge positive difference when I hooked up an Elecraft K2 +DEM 144/28MHz transverter. What a relief. Analogue beat digital. So out went the 7400.
In fact, in the past I have often parted from equipment which proved to be good in one area but were annoying in another. But the grass ain't always greener at the other side of the fence. Some years later I would buy such a rig again just because of its positive benefits. Maybe there is a learning point for me here?
Now the 7400 is perfect for 6m. Look at that huge monochrome backlit LCD screen; large frequency readout just above a high resolution S-meter. All info visual at glance without being the typical American x-mas tree. Icom designed a true icon when they released the IC746 back in '99 and the 7400 is even better!
Verdict: Instant gratification due to superb user interface & performance. Best in class ergonomics.

Icom IC756ProIII
A friend offered me to try this model for the weekend. I am familiar with its layout since I owned a ProII in the past (too?)for two years. Will this surpass the 7400 on a direct comparison? At Friday night I am already seduced by it's looks, it sure has the most beautiful analogue S-meter ever. If you can pick only 1 rig for your shack it would surely be this one (plus a 144 transverter). So I am a sucker for color screen LCD rigs after all?

During the weekend the 6m band has several Es openings, even some cross-Atlantic into the Caribbean area. I also tried this rig for one evening at another friends QTH who has a bigger 6m antenna. But how hard I try, there is no difference when it comes down to plain receiving performance when compared to my 7400.
The band scope with its slow refresh rate does not offer anything usable. Try using a real-time band scope like most SDR's offer and you instantly see what I mean. Since the S-meter is at a distance from the frequency readout I tried the optional digital S-meter. But it is a joke compared to the 7400. What a lovely looking rig, but it does not do what the 7400 does for me.
Verdict: No receiving advantage. User interface does not communicate to the operator like a 7400/746 does.
Useless, distracting band scope.

50MHz transceivers I have "tried" elsewhere

This is surely far from objective. But at least in terms of ergonomics it makes sense to me.

Yaesu FT950 & FT2000
While visiting the Hamradio fair at Friedrichshafen I managed to take a look at these models. At the end of the day there was plenty of time to play with both of them. There is an outdoors antenna connected. The AGC is a disaster and it sounds horrible on spikes or nearby clicks. User interface is classic for the 2000 with a nice large S-meter. But this classic isn't ergonomical.

Icom IC7600
Looks like a downsized 7700. Larger but even slower band scope than the ProIII. S-meter is ugly and difficult to read; should have been given a shadow on the needle to make it look semi 3 dimensional at least.
German magazine FUNKamateur offered their monthly edition for free during the fair. It had a test on the 7600 where it was revealed this rig suffers from 10-15dB higher phase noise in the 2-10 KHz range, compared to the former ProIII. As the writer states; when using a VHF/UHF transverter, this rig is less interesting for weak signal reception due to its relatively high phase noise. One month later the RSGB review by Peter Hart notices the same issue, but is keen enough to call it measurement was noise limited.

Elecraft K3
Serial #173 is at my friends QTH for more than 1.5 years now. It
is an exciting rig and has the best HF receiver, on paper. I have made several contacts on 6m with his set-up and large antenna. Filter settings below 150Hz are ringing, whatever the settings we tried. Ergonomically it is a disaster. Despite knowing the rig inside out, its owner isn't too happy either and finds himself using his Perseus SDR more often nowadays. I still would want one to add to my shack....someday.

The Icom IC7400 offers me the maximum pleasure for 50MHz operation.

What's next?

There are some ideas left. First I need to recapitulate all results and efforts this year.

And then there's the newly announced IC9100. It has HF+6+VHF+UHF+optional 23cm.
The format is similar to the 7400; that's surely a good point.
However, with so many bands in one rig I hope they do not choose the cheap way.
And despite its good looks it sure must be better before I switch again.


Enno, PF5X said...

Thanks for the informative blog on 50MHz trcv's.

An S-meter is nothing more than a rather irrelevant, but informative indication device. I can live completely without an S-meter. As long as I can HEAR the DX, everything is fine. "The most beautiful analog meter", come on Mark, get a life !! And by the way, how often are you looking at the meter during a difficult, "sweat in my hands and on my forehead" DX QSO ?? Exactly, N E V E R ... Because there is only one priority: get in the log of the DX.

Quite nice to see the the older generation TRCV-ers are still holding against modern DSP toys. I am still very satisfied with my K3 + PR6, but there are certain RX characteristics which still need improvement (e.g. AGC behaviour in conjunction with harsh audio).

Mark, PA5MW said...

Hi Enno,
Yes you sure are right about "making that QSO" is all that counts in the end.
However, from day one 'radio' has always fascinated me on 3 items: receiving sound, turning a VFO knob and an some S-meter.
The indication accuracy is also irrelevant to me.
Now there's 6 months to concentrate on other bands.
73 Mark