8 Sep
1998
8 Sep
'98
8:12 p.m.
Ok... It appears that the pins are _not_ numbered
conventionally (from
fig 6-5, Main PCB component side in the TechRef).
They seem to be :
2
4 o 5
o o
1 o o o 3
7 o 6 o 8
The pinout is (from Fig 6-3, main PCB schematic
1 TL (Telephone)
2 Gnd (System logic ground)
3 RxMD (Telephone line, Telephone common)
4 RxM (Acoustic coupler receive)
5 TxM (Acoustic coupler transmit)
6 Vdd (+5V output to power acoustic coupler)
7 TxMd (Telephone line)
8 RP (5V CMOS logic input. Beleived to be for an external ringing
detector unit for autoanswer. I can find no mention of this in the manuals)
There are 2 switches on the left. One is marked Orig/Ans and selectes
Originate or Answer tones. The other is marked ACOP/DIR and selects
Acoustic coupler or Direct Connect operation.
To link the thing up to a US phone line, direct connect :
Connect the phone line to pin 3 and pin 7 on the connector. The official
Tandy cable linked between a 'phone and the wall socket. The 'phone wires
go to pin 3 and pin 1
I verified your pinout info by tracing the connections and connected the
red phone wire to pin 7 and the green wire to pin 3. When I ran the
terminal program it hung and the internal speaker made a continuous static
hiss. I exited the terminal program with a break command, and the static
stopped.
One thing I'm confused about is your direction to connect the phone line to
pin 3 and 7, but saying that the Tandy cable goes to pins 3 and 1. I must
be missing something here. I looked up phone wiring, and found that the
green wire is called "Tip" and is like a common, and the red wire is
"Ring".
Any ideas on where I went wrong?
-Paul