Enterprises Original MFJ-557 Deluxe Morse Code Practice Oscillator Straight Key w/Volume Control

It's a great learning tool. You can use it as a keyer-only if you disconnect the wires. There are adjustment screws for pressure and gap. Battery use is adequate but it seems to wear down fast; sound is more robust if you use the adaptor. There is a somewhat annoying "pucker" sound when releasing the key each time, probably related to the speaker quality. Using an external one seems to eliminate that. I keep this on the end table next to the chair and tap out any words I see on the TV screen, almost obsessively. I heartily recommend this!

I miss the days when someone could walk in to any Radio Shack and buy a solid brass key for $6.95, BUT those days are gone :-( and I have to get used to it. This is a nice little straight key on a solid, heavy base, and I like having the oscillator to practice CW in the car (yes, I'm that nuts) when I'm not making actual contacts. About that, it's quite easy to modify this unit to quickly switch between practice and sending, mine has a 1/4" jack in the side for the transmitter, the kind that breaks tip connection when you plug in but if you've read this far you know what to do :-) Sorry MFJ, guess my warranty is void. And about MFJ, they are one of the best known and highest quality manufacturers in the business, well known and loved by many in the amateur radio world. Check out their guarantee. Before I sign off, one important warning: And I ain't pointing fingers, I'm just sayin. If you're planning to buy radio equipment, or ANY equipment for that matter, through Amazon or eBay or craigslist or a classified ad in the newspaper, do yourself a favor and view or download a catalog from the manufacturer (you can download the entire MFJ catalog from their website) or a reliable reseller (GigaParts, Ham City, etc.) to ensure that the price is in the right ballpark and the warranties etc are intact. Cause somebody might, hypothetically, buy this unit for $50 and try to sell it to you for $150. I'm just sayin. Cheers!

I have learned a lot of CW in the short time that I've had the MFJ-557. I think being able to actually hear my morse as I pound it out on this has really helped me start taking off in my CW journey. That being said, I was pretty horified when I opened up the cover to put a 9 volt in it. Holy moly, it's an absolute mess of wires, hot glue, and tape. The speaker is held on by tape to the plastic housing... just so cheap lol. I mean, I paid 90 bucks for this, and to be honest I don't even think I would expect that kind of internal build quality from something even $50 bucks. Overall, I am enjoying it though.

This is a solidly-built straight CW keyer. I've "book-learned" morse code, but keying morse is another thing. I practice using this with a morse code app that reads and decodes sound signals. Then I can tell whether I'm keying the letters and numbers correctly, and whether I'm pausing between letters and words correctly at different speeds. It works fine with either a 9V battery or a 12V DC adapter. The sound module is definitely analog, with some variation in pitch ("chirp"), but it's not a problem for practice. If connected to a radio, you must disconnect the key from the sound module hence it will not be used at all, so the chirp from the sound generation module isn't an issue. The tension and throw adjustments are a tried-and-true design that work well for light touch activation and release.

I bought this to help learn Morse code. Very sturdy build,arrived in perfect shape and works great. Would recommend

I played it after arriving, and several characters always played wrong; I thought it was my skill problem. I laid it aside on the table. Several months later, I saw there was a small rift in the key arm at the connection point accidentally. That was the cause of the problem. Now, I disassembled the oscillator from the key and used it with another key.

This is great for any newbies wanting to learn CW. It has a very heavy metal and rubber footed base and doesn't move around. The oscillator is loud and you can tweak the tone which is nice. The key is nicely adjustable so you can set it perfectly. I use the headphone jack as a line out and hooked it up to the microphone input on my computer and with a free morse decoder program I can see the code translated to text while I practice so I know if I'm keying correctly.

Very good quality, durability and ruggedness for the money. Oscillator connects to my headphones without any issue. This is a GREAT product for brushing up and learning Morse Code (CW) for beginners. The open posts can allow the operator to disconnect from the mounted straight key and connect it directly to a computer's COM port via USB connections so that the keyer could be used on computer aided tutorial programs. Or the oscillator can be connected to a higher quality straight key. The only minor draw back is that this particular straight key does not have an adjustable pivot for aligning the contact.

Meu pai foi telegrafista da rede ferroviária então comprei para presenteá-lo, ele amou todo o funcionamento.

mechanically it's good. works as it should. there was a plastic cover on the item itself that was broken. only cosmetic. doesn't hinder the actual function.. tried to contact seller, he just answered that he was glad I was happy.. I think there is a communication breakdown somewhere..

The headphone input has failed, and if I try to insert my headphone jack into the input it goes straight through. The item is still usable, but I can't use headphones. I will try to fix, or return for a new one.

The key took a while to arrive, but came well packed and once I put a battery in, instantly ready to go. The key handle was quite sharp around the key handle edges and uncomfortable and I had to file down those sharp plastic edges. Even then the flatness of the key is uncomfortable for me. The key appears to have acceptable tolerances, although taking a while to find the right tolerances for me personally. I definitely like it over all the other cheap rubbish on the market. It’s ok if you just want to practice on a budget. Otherwise buy a real key you will use in transmission and get a feed back system, or simply connect any key to this unit for an instant Morse practice. All in all, not bad, but I feel a little expensive, but I suppose get a better quality than most of the crap practice keys out there. This is the real thing to practice with though!

The packing of this item was not good enough, i received it in two pieces the finger plate and arm were detached from the body,the little spring was missing.the support bracket for the arm was bent,i was about to return the item when i found the little spring on my kitchen floor,i decided to repair the item myself,and now works ok.This item should have had a fragile sticker,NOT HAPPY.