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IZ3LSV

[San Dona' di P. JN]

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G8MNY  > TECH     12.06.13 20:41l 63 Lines 2886 Bytes #999 (0) @ WW
BID : 26005_GB7CIP
Read: GUEST
Subj: Yaesu DTMF Mic YM-48
Path: IZ3LSV<IV3YXW<I3XTY<I0OJJ<GB7CIP
Sent: 130612/1543Z @:GB7CIP.#32.GBR.EU #:26005 [Caterham Surrey GBR] $:26005_GB
From: G8MNY@GB7CIP.#32.GBR.EU
To  : TECH@WW

By G8MNY                                 (Revamp Nov 08)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)

I use mine with FT790/690/290 for DTMF control of a repeaters etc.

This is the diagram of the mic, I reverse engineered it ...

 旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴쩡컴컴컴컴컴쩡컴컴컴쩡컴컫컴컴컴컴>+5v rd
 �                      4x 1n      �           �   47u===  ===220u    pin 4
 � Keyboard         旼컴쩡컴쩡컴쩡�)컴컴컴컴컴�)컴컴컴컨컴컴�
 �  Matrix  rd     === === === === �           �            � ___ UP ye/bn
 � 1탠2컵�3컵횫컵컴�)컴�)컴�)컴캑  �           �            쳐o o컴컴>pin 6
 �  �   �   �   � bn�   �   �   �  �           �          wh�
 � 4탠5컵�6컵횭컵컴�)컴�)컴캑   �  �           �            � ___ DOWN bk/bl
 �  �   �   �   � or�   �   �   �  �           �            쳐o o컴컴>pin 7
 � 7탠8컵�9컵횮컵컴�)컴캑   �   �  �  3.52     �            �
 �  �   �   �   � ye�   �   �   �  �   MHz     �            � ___ PTT bk
 � *탠0컵�#컵횯컵컴캑   �   �   �  � 渼[]첼    �          bn쳐o o컴컴>pin 3
 � v�  g�  b�  w� 旼좔컴좔컴좔컴좔컨컨컴컴좆   �            �
 � i�  n�  k�  h쳐�9 14 13  12 11  1 7 osc8�  47            �
 �  �   �   쳐컴)캑5  c  row  DTMF IC      �   �            �
 �  �   쳐컴)컴�)캑4  o       8202  o/p    �   �   220u     �
 �  쳐컴)컴�)컴�)캑31 l 10    6     16     �   쳐컴캑쳐컴컴캑
 � === === === ===읕컴컴쩡컴컴쩡컴컴쩡컴컴켸 �/    +        �
 �  읕컴좔컴좔컴�      15k    �     쳐컴�2k2캑              �
 �     4x 1n    �      _�_    �     �        �\e     DTMF   �
2k2             �      / \e   �     �          읕12컴횸S컴컴�
 �              �     �   읕컴�     �              rd    bk �
 �        u1    �     � mute  �     �                       � MIC wh
 쳐컴쩡컴캑쳐컴�)컴컴컨컴컴컴�)컴컴�)컴100컴컴컴컫컴컴100컴�)컴컴컴컴>pin 2
Mic ===  +      �             �     쳐컴늘�47k�>3k3 DTMF    �
 �   �1n        �             �    10k +1u       � LEVEL    � Screen
 읕컴좔컴컴컴컴컨컴컴컴컴컴컴컨컴컴컨컴컴컴컴컴컴좔컴컴컴컴컨컴컴컴컴>Pin 1

Here the UP & DOWN button are connected to earth, but they can be to +5V for
some rigs! So check your rig handbook to see which it needs.

DTMF SYSTEM
This uses two pure sine wave tones controlled from a 4x4 keypad matrix, a low-
frequency tone & a high-frequency tone, to specify 1 of the 16 options.

Pressing 2 keys in the same row/column, normal results in a single tone.

 TONE HIGH 1209Hz 1336Hz 1477Hz 1633Hz
  LOW
  697 Hz     1      2      3      A
  770 Hz     4      5      6      B
  852 Hz     7      8      9      C
  941 Hz     *      0      #      D

Frequency tolerance:         �1.5%

The 2 tones must not clip & mix on the Tx/RF path/Rx as the DTMF Rx IC uses the
presence of more than 2 tones to identify the signal non DTMF & ignores it.


Why Don't U send an interesting bul?

73 de John G8MNY @ GB7CIP


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