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Ham Radio CD-ROM (Emerald Software) (1995).ISO
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pk232.21
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1990-09-10
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1KB
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24 lines
PK232.21
From: W5IFP@W5IFP
AS A RESULT OF THE BULLETIN I SENT ON USING 2 TNC'S ON ONE RTU,
SEVERAL HAVE REQUESTED THE SPECIFIC DATA ON THE PK-232 TNC.
THERE ARE SEVERAL WAYS TO MODIFY THE PK-232 TO ACCOMPLISH THE DATA
INVERSION ON THE SQUELCH OR REC. DATA LINE (RF-DCD). I HAVE A HEATHKIT
HK-232 SO I'LL USE THAT FOR EXPLANATION...HOPEFULLY THE CKT DESIGNATIONS
ARE THE SAME AS THE AEA PK-232. THE FOLLOWING IS A CROSS REF TO PIN #'S:
DATA MFJ-1270 RTU HK-232
---- ------ ------ ------
GND PIN 2 ------------- PIN 2 ------------ PIN 4
TX AUDIO PIN 1 ------------- PIN 1 ------------ PIN 2
RX AUDIO PIN 4 ------------- PIN 4 ------------ PIN 1
PTT PIN 3 ------------- PIN 3 ------------ PIN 5
RF-DCD (SQU) PIN 5 ---->------- PIN 3 ------- 1N914 1N914
* THE SQUELCH LINE MUST HAVE THE LOGIC SIGNAL INVERTED TO WORK . THIS CAN
BE DONE INTERNALLY BY CHANGING Q6 FROM A NPN TO A PNP TRANSISTOR. GARDEN
VARIETY WORKED OK (2N3906 OR 2N2905 OR EQ.)
CONTINUED IN FILE PK232.22