Radio Shack 420 - Manual (Page 5)

5
READ THIS BEFORE INSTALLATION
Your Caller ID system conforms to federal regulations, and
you can connect it to most telephone lines. However, each de-
vice that you connect to the phone line draws power from the
phone line. We refer to this power draw as the device’s
ringer
equivalence number , or REN. The REN is shown on the bot-
tom of your system.
If you are using more than one phone or other device on the
line, add up all the RENs. If the total is more than five, your
phone might not ring. In rural areas, a total REN of three
might impair ringer operation. If ringer operation is impaired,
remove a device from the line.
FCC STATEMENT
Your system complies with Part 68 of FCC Rules . You must,
upon request, provide the FCC Registration Number and the
REN to your phone company. These numbers are on the label
on the bottom of the system.
Note: You must not connect your system to:
• Coin-operated systems
• Party-line systems
• Most electronic key telephone systems
43-971.fm Page 5 Monday, August 16, 1999 4:12 PM