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Reviews Categories | Keyers & CW Keyboards | MFJ-403 Help

Reviews Summary for MFJ-403
MFJ-403 Reviews: 4 Average rating: 4.5/5 MSRP: $$59.95 & shipping
Description: This new MFJ Travel Keyer is a full-featured CW keyer with a built-in Iambic paddle. Its ultra-compact size is perfect for traveling or for home use with QRP or "big" rigs. Throw it in your briefcase alone with your MFJ QRPCub or other favorite rig on your next trip.

Send Beautiful CW with no effort
Self-completing dots and dashes and dot-dash memory is very forgiving of timing mistakes. It lets you perfectly form dots, dashes and spaces effortlessly for accurate professional sounding CW.

Adjust Speed on the Fly
A thumb wheel control lets you adjust speed on-the-fly 3 to 65 words-per-minute.

Adjustable Weight
Dot-dash weight is adjustable 25% to 75% to make your signal distinctive in a pile-up. It also lets you compensate for transmitter turn-on delay.

Sidetone with Speaker
A built-in sidetone with LM386 audio amplifier, speaker and volume control makes monitoring your sending easy. Sidetone pitch is adjustable 300 to 1000 Hz.

Keyer Modes
you can select a keyer mode to suit you -- Iambic mode A or B, fully automatic or semi-auto "bug" mode.

Reverse Paddle
If you're left handed or to adjust for your paddle wiring, you can reverse the sending a single letter you can completely control your keyer.

RF Proof
Effective RF proofing lets your MFJ-403 work in any strong RF environment.

Positive Keying Output
It's positive keying FET output lets you key nearly all modern transceivers and transmitters.

Battery Saver
You'll think your battery will last forever -- your keyer goes to sleep during periods of inactivity. Uses a readily available 9-volt battery.
Product is in production.
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WB0FDJ Rating: 5/5 Aug 8, 2011 11:25 Send this review to a friend
Does what it's supposed to.  Time owned: more than 12 months
I have a whole shelf full of QRP kits that I've built, most of them very simple (SWL20, OHR, a "Rockless) and an HW-8 that sees weekly use. Most of these do not come with a keyer. So I bought this, with some trepidation, for use with minimalist radios. It works. REALLY works. Runs off a 9V battery that will last a long while. Speed is easily adjusted "on the fly". For tune up I hit the red button, send "X" and I have key down for tuning. The Rube Goldberg looking paddles actually work rather well, though I fiddled with them at first to get them just right. I would recommend this for folks who want something very portable or who run simpler or older stuff (i.e. HW-8) that will not have built in keyer function. Effective. Reasonably cheap. Looks funny but gets the job done.
G4OTU Rating: 4/5 Aug 6, 2011 04:25 Send this review to a friend
Good keyer.  Time owned: more than 12 months
Had this now about a year . I do not use the built in paddle key - it is very hit and miss- but use the keyer with my Bencher paddle and TS530S.As a keyer it is great altho' it looks very cheap. The only fault is that the thumbwheel speed control would be better (more easily used) if mounted away from the jack sockets on the front panel.
K6SDW Rating: 4/5 Dec 14, 2008 15:54 Send this review to a friend
Funky but it works!  Time owned: more than 12 months
Actually, as crappy as it looks the action on the key is not bad....this makes an ok mobile/portable key cuz if it gets broken, oh well......if ya find one cheap enuff give it a try!
WA8MEA Rating: 5/5 Oct 28, 2006 15:57 Send this review to a friend
This is nice!  Time owned: 3 to 6 months
The folks at "Mighty Fine Junk" have gone out of there way once again. For under $60, I have got a nice quality iambic keyer. Didn't have to build it, either. Just installed the 9 volt battery, add a patch cord to the rig and away I send.

Variable speed, so I can slow 'er down for the novices and speed 'er up for the fast fists.

Nice sidetone, although I don't use it in this case because the rig has one. Also works great for portable use with my little qrp transmitters.

73, Bill - WA8MEA

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