Performing Modifications; Carrier Scan Vs. Time Scan - Kenwood R-5000 User Handbook Manual

There are several "configurable options" that a user with electronic skills can
add/change on the R-5000. These modifications vary in their usefulness, some actually
degrade the standard functions. Some are sold by radio dealers as high priced options, but are
easily done by the user with a little information. Some of the options that I have found are
described in detail below.

PERFORMING MODIFICATIONS

Most of these modifications involve simply cutting a diode or zero ohm jumper. Zero
ohm jumpers look like resistors with no color codes on them. They have no resistance (hence
the name zero ohm) but are used to make it easy to make or break continuity between two
points in a circuit.
These diodes or jumpers are vertically mounted with one end (the diode's anode end)
looping up. This makes enabling and disabling the option easy. To enable a particular option
you can cut the loop and move the wires to one side. To disable the option in the future, you
can simply re-solder the loop together.
Before you start, first understand that any modifications you do will void your warranty.
Second the R-5000 has delicate wires and fragile circuit boards, please take care when
handling them. Also the receiver has many CMOS parts that very sensitive to static electricity.
Use proper CMOS handling procedures. Appendix C has information on CMOS handling.
Please do not attempt any modifications unless you know what you are doing. If
in doubt, ask an experienced technician for assistance. The author assumes no
liability for the effectiveness or consequences resulting from these modifications.

CARRIER SCAN vs. TIME SCAN

The R-5000 has a scan function that allows the operator to scan channel groups
(Memory Scan) or scan between two designated frequencies (Program Scan). Refer to the
instruction manual for details on how both work. The standard scan function is called Time
Operated Scan. The operator initiates scanning by rotating the squelch knob until the audio is
muted. Then either Memory Scan or Program Scan is started. The radio will stop scanning
when squelch is broken by an signal and the busy light comes on. The receiver will
automatically return to scan after approximately 5 seconds whether or not the signal is still
present.
The R-5000 can be modified for Carrier Operated Scan. This mod allows the receiver to
return to scan only after there is no AM or FM signal. This modification involves cutting jumper
W64 on the IF board. Figure 1 shows the location of W64.
MODIFICATIONS
2