Kenwood TH-25A Instruction Manual page 16

step sizes, and alas I didn't write down what I found. If you want to play with this, go ahead.
On the TH-45AT:
(All frequencies are given in MHz.)
R18 in
R28 in
This is how the radio is delivered in the USA. The radio covers 438-450 MHz.
R18 in
R20 out
The radio is prohibited from tuning outside 440-450 MHz.
R18 out
R28 in
The radio will only tune from 215-230 MHz. Note that the PLL would not lock up! (What did you expect?
) Could it be possible that Kenwood originally planned a 220 version of this radio, but then scrapped their
plans?
R18 out
R28 out
The radio will tune from 200-500 MHz (on the display only - your PLL will not lock up over this entire
range). Transmitting is possible anywhere your PLL will lock up.
Some of the above codes are:
K USA
T England
X Australia
M Other Areas
These components are found on the flexible circuit board under the display. To get to them, take the radio
apart. Some unsoldering of obvious grounding wires may be necessary. You will see where the flexible
circuit board plugs into a socket on the main circuit board.
Before unplugging it, make sure you know what's in the memories, because they will be lost. Unplug the
flexible circuit board and unfold it so that the components are accessible. One of the fold-out parts of the
flexible board will look something like this:
+----------------+
! R R R D3 R R !
! 2 2 2 7 2 !
! 5 3 2 1 !
! !
! R O O R20!
! 2 O O R19!
! 6 O O R18!
! O O R28!
! !
! R !
! D4 6 !
! +-------+
The O's are solder pads.
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