[Elecraft] AT FIRST BLUSH - LogiKit CMOS 4 Keyer KIT!

[Tom Hammond NØSS]

I love building kits, especially electronic keyers, but...

One of the least enjoyable facets of building electronic devices
(for me anyway) is having to scrounge up difficult-to-find parts,
or components which aren't hard to find, BUT which I can't obtain
locally. It always seems I wind up having to go to more than one
vendor, and end up paying a LOT of cash for shipping and (in some
instances) 'handling'. Then you have to determine what type of
case you want to use (it'll almost always be too big).

And don't forget the pain of going from place to place, trying to
find acceptable pushbuttons for the message buttons. The SWITCH
must...

   1) be easy to actuate, but not to easy.
   2) give you a bit of tactile feedback, so you'll know you
      really DID press it.
   3) be small enough to FIT into the case
   4) be easy to install
   5) most of all, be RELIABLE and not prone to becoming noisy
      after only a short lifespan

Idiom Press has produced CMOS Super Keyer kits for a bunch of
years... probably neigh on the 20 anyway. The problem was that
their 'kit' only included the PC board and all of the parts which
mounted on the PC board. But that was it... none of the other
required parts were included in the kit, leaving it up to the
builder to decide HOW he wanted to outfit his keyer, and then to
go FIND all of the missing parts.

Most of the missing parts could be found at the local Radio
Shack. But you could NOT find reasonably priced pushbuttons
there! By the time I bought all of the remaining parts at 'th
Shack, I had invested a total of about $85 in complete list of
parts, and sometimes this still didn't include the case. I LOVED
the keyer, but HATED the parts search.

Well, Idiom Press/Logikey Co. (AKA Bob Locher, W9KNI) finally did
it!

They've come out with a new keyer kit, aptly dubbed the "Logikit
CMOS4".

It's a COMPLETE(!!) kit, including all required components and a
KILLER case and set of tactile pushbutton message switches, all
for very nearly the price I was having to pay for the old kit
plus individual parts from R/S.

I am fortunate in that I was able to FT (Field Test) what I think
was only the second Logikit CMOS 4 ever produced. I also got to
help proof the assembly manual as well. Still haven't seen the
User Instruction Manual yet, but I do know it has been printed.

The Logikit CMOS 4 comes in an all too small box, belying it's
eventual small size.

Assembly of the kit went without a single hitch... everything fit
where it was supposed to, and all parts were provided... nothing
missing.

The assembly manual has you first install the monitor speaker
onto the bottom half of the keyer case. Then you install the
connectors which also mount onto the bottom of the case. There
are only three connectors to mount: external DC input (5.5mm x
2.5mm coaxial jack), paddle input (1/8" stereo jack) and keyer
output (RCA jack). The installation of the DC power connector was
a bit 'tight' since there was little 'wiggle room' between the
jack and the speaker. But the manual offers easy-to-follow steps
to simplify the installation of the power jack.

 From there, you begin installing components.

First to be populated is the pushbutton mounting board. It gets
four (4) small PC board-mount tactile feedback pushbuttons with
pushbutton caps about 1/4" in diameter. The buttons are arranged
in two groups of two and have a nice solid 'feel' to them.

Next to be populated was the main (keyer) PC board. Parts
installation goes logically and builders should experience no
problems with assembly of the PC board.

Final assembly consists of attaching the main and pushbutton PC
boards and connecting the few wires which attach to devices not
on the PC board.

The most difficult part of the entire (c. 3-hour) assembly was
soldering one of the leads to a lug on the speed control pot
which is quite close to the bottom of the chassis, and difficult
to access. Were I do build another of these kits, and I may well
do so, I think I'd attach the speed control wires to the pot
BEFORE I mounted it to the front panel of the keyer.

Final assembly was a snap. The two halves of the case fit
together like a glove (similar to cases made by that
"E-something" company.. <G>).

Operationally, the Logikit CMOS 4 performs just like its older
siblings. It's silky smooth to send with, easy to program, and
keys either the 'positive' keylines of 'modern' transceivers OR
the grid-blocked keylines of many of the older rigs as well.

CW speed is between 5 and 60 WPM, with an additional 'high speed'
range (70-990 WPM) for meteor-scatter ops. Yes, you read
correctly... all the way up to 990 WPM!!! For us mere mortals,
who can no longer copy (or send) 990 WPM, you have the ability to
select a user-programmable speed range. I chose 18-40 WPM, but
ANY combination of two speeds between 5 and 60 WPM are available
to you. And the Speed Control is linear.

Keying WEIGHTING is fully adjustable between 25% and 75%, with
50% weighting being the default.

The keyer also includes keying compensation, to make up for the
small (mS) delay between the key is hit and the output arrives,
often resulting in a slightly 'lighter' than normal character. It
appears the best compensation for my K2 is between 2mS and
4mS...! Almost not required.

The monitor speaker has ample volume. And, a volume control is
provided on the bottom of the case to adjust it to the desired
listening level.

There are a LOT more features of this keyer, but you can read
about them on the Idiom Press web site,

   (http://www.idiompress.com/cmos4.html)

it'd take much too long to list all of them here.

In short (too late for that now, Tom), this is just the keyer
I've been looking (and hoping) for easily 20 years. 'Bout
time! Thanks Bob.

73 to all,

Tom Hammond N0SS

PS

I have NO interest whatsoever in Idiom Press or the Logikey Co. I
just happen to like their products.