Congratulations on your choice of the MFJ-8621 Packet Only Data Radio. Please read
this manual thoroughly before attempting to operate your unit. Let's begin with a look
at some useful MFJ-8621 Features:
FEATURES
Packet-Only Performance: The MFJ-8621 is designed from the ground up for packet.
This means you'll get uncompromising performance at all data rates--on AFSK or FSK--
for a fraction of what you'd pay for a converted voice radio.
Cool Running: The MFJ-8621 draws only 25 mA on receive, and less than 1 A on
transmit. Run it 24 hours a day 365 days a year, or pack it with your lap-top and take
it on the road.
Sensitive: Motorola-IC based receiver circuitry recovers data from weak signals for
better throughput and fewer collisions.
Made-For-Data Filters: Optimize your receiver for wide 9600-baud signals or narrow
1200-baud signals. No other radio does this!
Rugged 5-Watt Transmitter: All the power you need to get the job done without
creating needless interference at distant nodes.
Clean Unsquelched Data Output: The MFJ-8621 uses a wide-response DC-coupled
line driver rather than a speaker amp for flawless signal recovery.
Note: Your TNC must have full DCD (Data Carrier Detect) in order to work with radios
that have full unsquelched AFSK output.
Lightning-Fast TXD: Set TXD low! PIN-diode switching, continuous-running receiver,
and crystal control deliver ultra-fast switching.
Twin Modulators: Varactor-modulation for true-FM at 9600-baud and reactance
modulation for mic-level signals at 1200 baud provide ultra-clean FSK and AFSK.
Simple Setup: The MFJ-8621 is compatible with virtually all up-to-date TNC-2 modems.
Easy To Rechannel: Run your MFJ-8621 with supplied crystals on 145.01 MHz, or
order custom crystals for the channel of your choice. Simple step-by-step instructions
illustrate how to exchange crystals and set on frequency without expensive test
equipment.
The Right Tool For The Job: Your MFJ-8621 was designed from scratch for fast,
clean packet communication and nothing else! Whether you are monitoring the local
DX cluster or breaking new ground at 9600, you can look forward to years of hands-off
service.
