Advertisement
Quick Links
Mini Keying Adapter (MINI-KA)
The Mini Keying Adapter acts as a buffer between your electronic keyer or computer and
certain transmitters and transceivers that require significant keying current. For
applications that do not require optical isolation, the Mini-KA offers a solution low in
cost and complexity.
Features of the Mini Keying Adapter Kit:
Keys solid state transmitters or transceivers
Current capacity up to 4A with low ON resistance
Works with any electronic keyer, bug or straight key
Can also be used with computer input for use with Morse code software
Compact size (38 mm x 38 mm / 1.5" x 1.5")
Simple screw clamp type terminal block connector
NOTE – Prototype board, may appear different than production kits.
Mini Keying Adapter
01/07/2016
Page 1 of 6
Advertisement
Related Manuals for HamGadgets Mini Keying Adapter
Summary of Contents for HamGadgets Mini Keying Adapter
- Page 1 Mini Keying Adapter (MINI-KA) The Mini Keying Adapter acts as a buffer between your electronic keyer or computer and certain transmitters and transceivers that require significant keying current. For applications that do not require optical isolation, the Mini-KA offers a solution low in cost and complexity.
-
Page 2: Parts List
Parts List Part Value Mini Keying Adapter printed circuit board 1N4148 diode 2N7000 MOSFET AOI516 or IRFU220 MOSFET 100 K Ω 1/4W resistor (Brown-Black-Yellow) R1, R2 6-position terminal block Assembling the Kit Always use good static prevention practices when working with static sensitive parts. This means you should wear a grounding strap when possible, or work on a static-dissipative work surface. - Page 3 It will work the other way, of course, but it might be more difficult to make connections. You might want to hold it in place with a piece of tape while soldering. Mini Keying Adapter 01/07/2016 Page 3 of 6...
- Page 4 Keying Adapter with a straight key, bug, some other electronic keyer, or even a computer serial or parallel output signal. If your radio immediately starts transmitting when you connect the keyer to the Mini Keying Adapter, you’ve probably got the IN/GND wires reversed.
-
Page 5: Theory Of Operation
Theory of Operation In logic terms, the Mini Keying Adapter consists of two inverter/buffer stages. The gate of MOSFET transistor Q1 is normally held high by resistor R1, keeping Q1 turned ON (conducting). Q1 presents a low resistance to ground, keeping the gate of Q2 near ground potential. - Page 6 Schematic and PCB Diagrams Mini Keying Adapter 01/07/2016 Page 6 of 6...