Manager - NA4M
Manager Notes

Reviews For: Idiom Press/Ham Supply Logikit CMOS 4 Morse Code Keyer

Category: Keyers & CW Keyboards

eMail Subscription

Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews are posted.
Review Summary For : Idiom Press/Ham Supply Logikit CMOS 4 Morse Code Keyer
Reviews: 94MSRP: 99.95 - 139.95
The CMOS 4 is the little brother to the world famous K-5 Keyer. Unmatched feature list, with the best operator interface available. Additional features include: greater protection against voltage spikes, lightning etc.; all stainless hardware; internal volume control; updated enclosure design; 3-AAA cells will run Keyer for months, or accepts 9-12 volts DC. See Website for full and complete details.
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
KB1NO Rating: 2021-05-31
Great Performing Keyer. Just bought a 2nd one. Time Owned: more than 12 months.
I've had an original Idiom Press CMOS-4 keyer for about 10 years. Initially I used it for code practice using the built in speaker, then with radios. The simple appearance hides its amazing flexibility. Settings are made directly with CW commands or the speed pot. A long list of Iambic emulations are available, including my favorite one. I'm using it with my IC-7300 as I prefer it to the built-in keyer. It works for months or longer powered by the internal batteries.
I was happy to find that Ham Supply is now offering these keyers fully assembled and tested, so I bought a 2nd one to use with a different radio. Wayne at Ham Supply was very responsive and the keyer arrived quickly and in perfect condition. The internal construction shows high quality workmanship. (Made in USA). The battery holder is improved vs my original.
I highly recommend this keyer.
W0AZ Rating: 2020-07-16
Excellent, small external keyer Time Owned: 0 to 3 months.
I’ve been using a Logikey K-1 keyer for decades - currently, it’s keying my FT-1000MP.

Recently, I acquired an IC-7300 and even though it, like the Yaesu, has an internal keyer, I am so used to using the Logikey I decided to get one for the Icom as well.

The “little brother” is an amazingly feature rich keyer just like all of the others in the history of the Logikey line.

In Logikey keying mode, they simply feel “right” to me after all these years. I’m glad I got another one.
K5NT Rating: 2019-12-13
An improvement on the Logikey K3 Time Owned: 0 to 3 months.
I decided to retire my Logikey K3 and take a chance on the CMOS-4. It looks like a good decision so far. It programs just like the K3, but has more features. Having four memory buttons instead of six will not impact my contesting, as there are internal memories and other features that can be used. The manual is written clearly. The CMOS technology should make it less power hungry than the K3. I installed three AAA Duracells in the internal battery pack, and it will be interesting to see how long they last. Ham Supply's service is excellent.
K6CTW Rating: 2019-10-13
Superb! Time Owned: 0 to 3 months.
Been using bugs for 50+ years and decided I wanted to teach my left hand to send code with a keyer. This is by far the best keyer available. Read the manual 2 times before it arrived and so it was very simple to get it on the air. The options are easy to use and the manual is very complete. You cannot go wrong with this unit. It even does a great job keying my Drake C-Line.
VE4AMN Rating: 2012-04-22
excellent Time Owned: 0 to 3 months.
Picked this up at a hamfest, so did not build the kit. Keyer works well with my Kenwood hybrids. The keying is smooth and the manual clearly takes you through the steps of storing messages. It is almost as good as having my butler send cw for me! The unit is compact so would be fine for portable operation. This is important since one can store a lot of information in the message banks and you can take the programming with you on the road.

It keys older hybrid (not cathode keyed) rigs and modern solid state units, but one needs to change an internal jumper to switch. My
my one wish would be to have an integrated universal keyer interface.

It also supports programming of exotic (for me, much of the hobby remains exotic) functions such as setting up a beacon.

W1JA Rating: 2011-03-17
Bestest keyer ever Time Owned: 6 to 12 months.
I already have the original CMOS keyer that I built in the 1990 from a QST article, and also a Logikey K3 that I bought in 2001 for another rig, so I'm familiar with the superb way these keyers are controlled (via morse commands sent from the paddle) and the superb way these keyers operate.

This keyer is the best yet. It fits in small spaces, it runs for a year or more on a set of batteries, it has a built-in sidetone with adjustable volume and pitch, it somehow magically makes me send with fewer errors... I love this keyer.

I bought the kit, so I got to enjoy an evening of Heathkit-style fun putting it together. I have posted some pictures of the construction process at
W3CUV Rating: 2010-03-27
Worth the dough Time Owned: 0 to 3 months.
Let me say right off that the CMOS-4 is much better than the internal keyer in my Kenwood TS-570. Fewer sending errors, that's the main reason I bought this keyer. It produces smooth and accurate keying.

This kit wasn't the easiest thing I've built lately, but I successfully finished it in two sessions. I suggest stoping when the PCB's are completed and resuming on the 2nd day to connect the peripherals.

The instructions go into extreme detail for most of the steps, but failed to say which way the battery box should point. And there isn't any spare room to fit it in next to the key jack. Once you stick it to the adhesive on the back of the speaker, it's there forever. So there should be a warning here, you don't get a second chance.

The tutorial is good. In a conversational style, it walks you through how to use your new keyer and soon you become familiar with most of it's many bells and whistles. But one thing I noticed at this point, I can't tell any difference with "Autospace" turned on or off ???

Overall though, I'm quite satisfied with the CMOS-4, and still think it's the best one out there, but give it only four stars because of it's tricky assembly.

VK7JB Rating: 2009-12-23
Perfect score! Time Owned: 0 to 3 months.
I'm a novice kit builder, but this kit almost fell together, with only a little coaching from me. No missing parts, great quality board and unambiguous, detailed instructions made for a fun and rewarding kit building experience over 3 winter nights. I'm now proud to own a keyer that offers more features than I'll ever need, that looks great in my shack and that worked perfectly from the time I connected the battery.
Thanks Idiom Press!
TOPPER Rating: 2009-07-22
Glad I bought it! Time Owned: more than 12 months.
Went together well, way more features than I needed, & some I love, like auto-spacing. Excellent tuetorial. Running on same internal batteries for years. Wish it had a 'practice' mode.

Note: After some years unit developed a fault; cpu chip was replaced by Rob for free. Idiom Press has a friend for life! tnx, N7AG
AH6ZZ Rating: 2009-07-19
Great keyer, kit a challenge Time Owned: 0 to 3 months.
Caution: I am not a good CW op; bought this keyer to get my speed up and my words to sound like words instead of word puzzles.

Point One: this is a great keyer; it includes a mini-course in Keyer 101; easy to learn, easy to "program" and a joy for the not-so-talented wannabe cw op (like me). Bottom line: it encourages you to want to work cw.

Point Two: this is not an easy "one or two evening" kit, unless you work about four hours two evenings; it is challenging -- not impossible for the first timer, but he/she better be a talented one; I have spent 40+ years in electronics -- and there lies my problem -- old eyes and shaky hands will be challenged.

Buy the kit. It was good for me to sweat out all those little components and look through the magnifying glass after every solder joint. The joy of hearing it say --- -.- is worth it.