View Full Version : Kenwood TS-940S

02-24-2010, 08:47 PM
I'll start this review off with a bit of history involving me and the '940, then comment on the one I presently own:

First exposure to Kenwood's (at the time) flagship radio was through my friend Hank, KA8RZT (SK). He bought a second-hand rig in the early 90s, previously having used a TS-440SAT for most of his HF operating.

The '940 was a capable, fully featured rig and it made a lasting impression on me.

Fast forward to 2006 - a friend was cleaning out her late hubby's shack and I got a '940 with speaker for a decent price.

I didn't like this one after using it for a while. I ended up trading it off. Its less-than-stellar power-supply cooling arrangement helped that decision along, as I didn't want something that isn't utterly reliable in the lineup.

Recently I got the wants for another...started doing a little research...found out that the one I used to own (ser# 5,xxx,xxx) was one of the very first rigs out the gate - and as such had a few inherent flaws which were corrected in later runs. Many folks opine that any serial number above 7 million is "safe", while others swear that the magic number is 8 or even 9 million+.

Off shopping I went.

The operational unit which finally hit the doorstep is of the 7mil run. Another - waiting to be fixed - is a 10mil unit.

There is a marked difference between "old" and "new", although the later version's IF board can be swapped into an earlier unit and this will cure many of the purported evils. Anyone wishing to keep theirs around should look into upgrading the power supply cooling arrangement; the two I have are getting ball-bearing computer fans installed along with upgraded AVR-board components.

Some owners gripe that you cannot select a narrow SSB filter using the Wide/Narrow switch, but that's supposedly what the Slope Tuning controls are for. On CW, though, this thing is a beast: Its VBT, AF Filter and CW Pitch controls make an in-the-noise signal pop right out at you. The AGC cannot be defeated in AM or FM modes via the front-panel control, yet some owners claim that it can. Perhaps this is true where a late-model rig is concerned?

There is no sub-receiver built into the '940 (a la TS-950SD) but I'm working on a way to digitally slave an R-5000 to the rig and emulate a '950. It'll appear as one to HRD, N4PY's software, K1MM's Logger and a number of other CAT programs.

These rigs are getting old and some say "questionable" in the reliability department but a semi-skilled tech should have no problem keeping one on the air. Pay close attention to the AVR pass-transistor cooling fan (or replace it). Most problems of an intermittent nature with a rig this old can be traced to questionable connectors on the various circuit boards. Resoldering them is a tedious job but aside from replacing memory batteries (or re-peaking the VCO tuning coils, if necessary) is usually all that's required in the way of maintenance to keep the '940 running along smoothly.

The more I work with mine, the more I'm convinced that the '940 has been getting an unfair rap by those who aren't familiar with or experienced in proper troubleshooting procedures.

Have to give it a 5 out of 5, although there are a couple of items I wish Kenwood would have implemented a little differently. All the same, these can be "modded into" the design.