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- KENWOOD TH205E 144MHZ FM HANDSET, EXTENDING FREQUENCY COVERAGE.
- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
- It is possible to extend and/or alter the frequency coverage on this
- radio by a very simple mod. Please note that I will not be responsible
- for any mods which go wrong, or any guarantees which may be invalidated
- by the following mods. Its up to you whether you take the back off your
- radio, but the mods have worked successfully on two TH205E's to my
- knowledge.
-
- 1) Remove the belt clip, if fitted.
- 2) You will see four screws on the back, slightly recessed, right at
- the edge of the set, remove these and carefully turn the set over.
- 3) Carefully lift off the front panel. I say "carefully", and I mean
- it, as the front panel is attached to the rest of the radio by means
- of lightweight ribbon cables. Mark these cables so that you know
- which way round they plug in, just in case they get pulled out by
- accident.
- 4) On the PCB which is mounted behind the front panel, you will see a
- set of jumpers thus:
-
- ========
- ! ! ! !
- ! ! ! !
- ! ! ! !
-
- 5) The PCB is labelled as to which is Jumper # 1. For the purpose of
- this mod, you can ignore J4. As supplied, J1 and J3 are connected,
-
- J2 is not. (UK version). As supplied you have 144.000 to 145.995 mhz,
- +- 600khz rptr shift, and 5khz steps.
-
- 6) Altering the jumpers:
-
- JP1 JP2 JP3 RX TX STEP SHIFT
-
- ___________________________________________________________________
-
- * * * 144.0 - 145.990 AS RX 10K -----
-
- * * - 141.0 - 162.995 144.0-145.995 5K -----
-
- * - * 144.0 - 145.995 AS RX 5K +- 600khz
-
- * - - 144.0 - 147.995 AS RX 5K +- 600khz
-
- - * - 141.0 - 162.995 142.0-148.995 5K +- 600khz
-
- - - - 141.0 - 162.995 AS RX 5K +- 600khz
-
- - * * 134.0 - 147.995 AS RX 5K +- 600khz #
-
- - - * 154.0 - 173.995 AS RX 5K +- 600khz #
-
- ____________________________________________________________________
-
- # > This mod only changes the display, for proper operation, other
- mods are needed to the transmitter.
-
- - > NO JUMPER
- * > JUMPER
-
- When the required mod has been carried out, it will be necessary to
- re-set the system. The re-set procedure is: ON - OFF - ON.
- The European version has jumpers 1 and 3 in position. the VCO can work
- between 141 - 163 MHZ. Outside these ranges, further mods are needed,
- which unfortunately I do not have to hand.
-
- One point to watch is that if you are not careful with your soldering,
- you can cause an earthing problem, which will result in a hum or buzz
- being transmitted along with your audio.
-
- Have fun! 73 de John, G0HMZ @ GB7HMZ [MATLOCK]
-