It says practice machine; can it be used in real life applications? If not would you recommend a unit that would?

The key can be removed from the practice oscillator base, and hooked up to most CW transceiver / transmitters for real world applications after you are done using it for audible practice .

can you hook paddles up instead of the straight key ?

You can not. Paddles need additional intelligence and an additional circuit that will send dots or dashes when you move the paddles right or left. This is essentially like the buzzer on a door...as long as you press it buzzes, when you stop it stops.

Yes, you could transmit with it, but straight keys are so cheap why not just buy another one.

can you wire this to a radio

Dear Writer, 10x 4 msg. You can do if your radio has MORSE key wire's input (not morse key speaker input). Simply un-screw two wires which connects to morse key from inbuilt MFJ device then connect radio's morse key wires. Have a g8t day. 73. Mayank Gupta (VU3MFT)

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

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

Product ID: 8370037

Details

Brand
MFJ
Color
Black
Controller Type
Button Control
Electric fan design
Blower
Mounting Type
Floor Mount
Power Source
DC or Battery

🎧Earphone jack for private practice

🔋Dual power: 9V battery or 110VAC

🎚️Adjustable volume & tone control

25310 kr

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Description

📡 Master Morse Like a Pro — Anywhere, Anytime!

PRIVATE OR LOUD - Use the earphone jack for discreet practice or plug in an external speaker for classroom-level volume.
STAY PUT SEND SMOOTH - Heavy steel non-skid base keeps your key steady for flawless code sending.
CUSTOM SOUND EXPERIENCE - Fine-tune your tone from squeaky high to booming low with volume control that won’t disturb others.
PRACTICE ANYWHERE ANYTIME - Compact and portable design lets you sharpen your Morse skills at home, work, or on the go.
BUILT TO LAST WITH CONFIDENCE - Backed by MFJ’s famous one-year No Matter What warranty for worry-free mastery.

The MFJ-557 Deluxe Morse Code Practice Oscillator is a portable, heavy-steel based straight key with adjustable volume and tone controls, earphone jack, and dual power options (9V battery or 110VAC). Designed for serious CW enthusiasts, it offers stable, private, or amplified practice sessions backed by a one-year no-questions-asked warranty.

Specifications

ASIN	B00OAHNA10
Best Sellers Rank	#511,976 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #81 in Industrial Electrical Oscillators
Blade Material	Plastic
Brand Name	MFJ
Color	Black
Connector Type	Standard AC Power Plug
Control Method	Touch
Controller Type	Button Control
Customer Reviews	4.2 4.2 out of 5 stars (377)
Electric Fan Design	Blower
Finish Type	Metallic
Indoor Outdoor Usage	Indoor
Is Product Cordless	No
Item Dimensions D x W x H	3.75"D x 8.5"W x 2.25"H
Item Weight	1.3 Pounds
Manufacturer	MFJ
Material	Alloy Steel
Model Name	MFJ-557
Model Number	MFJ-557
Mounting Type	Floor Mount
Number of Blades	3
Number of Speeds	3
Part Number	MFJ-557
Power Source	DC or Battery
Room Type	Classroom
Size	Medium
Special Features	Portable
Style	Modern
UPC	744288052305 796793893676 702646177954 757183018185
Unit Count	1.0 Count
Voltage	9 Volts

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25310 kr

Duties & taxes included

In stock

Sold byAmazon IcelandDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Iceland.

Secure transaction

Trustpilot

TrustScore 4.5 | 7,300+ reviews

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