Specifications

CHAPTER 4

PACKET RADIO

4.1 Overview

In the last several years Packet has grown to become perhaps the most

popular digital mode on the amateur bands. Although Packet can be

found on HF (primarily on the 20 meter band) it is most popular on the

VHF and UHF FM bands. This chapter will start with general Packet

operation and then discuss VHF and UHF Packet. Packet on the HF bands

requires some special considerations, so we will leave it until the

end of this chapter.

Your PK-900 can operate HF or VHF Packet (on Radio port 2) and any

other digital mode on Radio port 1 at the same time. This feature can

come in handy allowing you to keep an "ear" on local packet activity

while operating on any of the other digital modes normally found on

HF. Sorting out the data from both Radio ports also requires some

special considerations and will be discussed later in the chapter

after HF Packet operation has been covered.

4.1.1 Getting Started

You can learn quite a bit about Packet operation with the

PK-900 before even connecting it to a transceiver. For your first

packet practice, the PK-900 will be connected in a "loopback"

circuit as done in the "Quick Check" performed in Chapter 2. In this

configuration, the PK-900 will "talk to itself" which allows you to

become familiar with packet before actually going on the air.

4.1.2 Making the Loopback Connection

Make sure the PK-900 is turned OFF and power is removed before

performing one of the following.

I Locate the WIRE "Loop-back" jumper and insert it into pins

1 and 4 of the RADIO-1 connector on the PK-900 rear panel.

II If you cannot locate the wire "Loop-back" jumper and have a

spare Radio cable, you may construct the following:

1. Get the unused Radio Cable mentioned in Chapter 3.

2. Strip about 1/4 inch of insulation from the Green and White

wires at the "radio" end of the cable.

3. Join the Green and White wires by twisting them together

gently.

4. Insert the 5-pin DIN connector end of the cable into the

"RADIO-1" connector on the PK-900's rear panel.

5. Go on to section 4.2.

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