Kenwood TH78A Instructions

I uploaded the following texts to the old norcal AX.25 packet network way back around 1992. I put the
information together from various sources and included the receiver sensitivity measurements I did
after modifying my TH78A. The upload capacity of the network was pretty small back then so each file
needed to be kept small. I am leaving them in the original order for posterity but editing the layout to
be more readable since they were originally plain text. You can still find the archive of the original 16
files that comprised the mod list is you search hard enough. Ken Mazie (KD6IZY)
These are modifications for the Kenwood TH-78a dual band hand held radio. They have been compiled
through correspondence with Kenwood, and tidbits picked up here and there. The author assumes NO
RESPONSIBILITY for these mods or what they do to your radio, or what YOU do to your radio attempting
to perform them. In other words, you break it, it's your fault.
=============================================================================
CROSSBAND REPEAT:
The user manual claims the unit will cross band repeat out of the box, this is not true. For the TH-78a to
cross band repeat you must remove diode D4. Unfortunately you need to reset the CPU which will clear
your preset memories (NOTE: See "cloning"). Write down what you have programmed into the TH-78a
and then hold down the "M" key and power up the unit. All LCD segments should light up. The CPU is
Kenwood TH78A Mod Instructions
The Kenwood TH-78A is a sophisticated dual-band for 144 and 440 MHz. It
has built-in DTSS and paging functions, alphanumeric memory and
message paging. Additionally it has dual-frequency receive capability
(including VHF+VHF and UHF+UHF). There are 50 multi-function memory
channels plus 2 call channels (the optional ME-1 increases the memory
capacity to 250 memories). With alphanumeric tagging the memory
capacity is 25 channels (or 125 with ME-1). The operator can choose from 8
different scan types for each band (with carrier or time operation). DTSS
allows DTMF access to the transceiver. The TH-78A features a two line LCD,
10 minute time-out timer and backlit keypad.
The receive range of this HT is: 118-173.995 and 438-449.995 MHz. Three
RF output levels are provided. On 144 MHz with external power output is:
5.0/0.5/0.02 watts. On 440 MHz with external power output is:
5.0/0.5/0.01 watts.
1.95x5.28x1.61 inches 0.88 Lbs. (50x134x41mm 400g)
KENWOOD TH-78A MODS