Inside of IC-U1


Front of IC-U1

Setting place of UT-118 (Remove the battery pack)

Remover the cover

Installed UT-118

UT-118 Option

UT-118's Pin Assign
3DMODto FM modulator(to 9600bps packet input) 28VCC_8V8V(4.5V-8.5V)
4AMODINVoice INPUT27TXDFlash memory output
5F_RXDFlash memory input26232_TXSlow Data Output
6BUSY_CSQ INPUT25232_RXSlow Data Input
7RESReset for CPU24RMUTEMute signal
8NC 23FMDETfrom FM Demodulator
9NC 22DAFOUTAudio Output from Digital
10NC 21REFMODsame as DMOD(thru buffer)
11NC 20NC 
12GNDDigital GND19FLASHFlash memory writting control
13GNDDigital GND18RXD_2_Cto CPU of UT-118
14P01To GND when adjusting.17TXD_2_Cfrom CPU of UT-118
15NC 16NC 

If this option is connected with FM rig according to the following block diagram, you make the rig of the DV mode. (This diagram is the option UT-115 of IC-2200H. But circuit is same as UT-118. UT-118 changes software for multi path.) And you must add the PTT control curcuit for this diagram. When PTTIN_C set Low level and GMSK signal come from this option board, PTTOUT is going to Low level. Therefore, you can use to this signal for rig's PTT contraol.

Board Layout, Block Diagram and  Circuit. You can download the whole service manual of IC-2200H from
Control method between H8/3687 and UT-118 is same as ID-1 control command. Signal lines are RXD_2_C(18pin) and TXD_2_C(17pin).(9600bps, 8bits, none parity, 1 stip bit)

Electric Spec. of each pin

 Pin NumberElectric Spec.I/ORemarks
to FM Modulator(DMOD)3350mVp-pOto Radio packet connecter
from FM Demodulator(FMDET)23600mVp-pIfrom Radio packet connecter
Audio Output(DAFOUT)22 O 
Audio Input(AMODIN)4500mVp-pI 
PTTIN_C1RX:High TX:LowIPull Down with 47K
PTTOUT_C2RX:High TX:LowOOpen Colecter
RMUTE24When Mute:LowOOpen Colecter
RXD_2_C183.3V CMOSIchange to RS232C
TXD_2_C173.3V CMOSOchange to RS232C(Open Colecter)
BUSY_C6When received:LowPull Down with 47K

Last Modified 02/09/2008
CopyRight(c) 2005 All Rights Reserved.
Satoshi Yasuda 7M3TJZ/AD6GZ