Ramsey Electronics TT1 Instruction Manual - page 6
TT1
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voltage at the base of Q2 turns Q2 on. With Q2 turned on it’s collector and
also the base of Q1 are pulled low. With Q1’s base pulled low, Q1 is turned
on (remember PNP transistor). At this time Q1 passes the voltage from the
remote jack to the base of Q3 turning Q3 on. Q3, being turned on, pulls it’s
collector (which is connected to the remote jack) low, activating the tape
recorder. At this time the audio (which comes in on the same telephone
lines) comes down to C1 and C2 in the audio section. C1 and C2 block the
incoming DC voltage but pass the audio through. The audio then goes
through a 100:1 divider, R6 and R7, and is applied to the tape recorder mike
jack. Diodes D6 and D7 are used for protection and will never allow more
than .7 volts of audio to reach the recorders “Mike” jack (you never know
what noise can come over the line when you’re on the phone).
There, now that we’ve got all that out of the way, there is just one more
thing to discuss, the “Power” and “Mode” switches. The “Power” switch
connects the TT1 to your tape recorders remote jack. When this switch is in
the “Off” position the TT1 will have no effect on the tape recorders operation
(i.e. the tape recorder is in manual operation).
When this switch is in the “On” position the power from the remote jack
can be brought into the TT1 to be used to turn on and off the tape recorder
remotely (i.e. remote operation).
The “Mode” switch is used when you wish to either be in the “Record”
mode (with the tape recorders “Record” button pushed) or “Playback” mode
(with the tape recorders “Play” button pushed) for listening to what has been
recorded (remember to rewind the tape first).
Now, before we get building, check the parts that came in your kit
with the parts list on the next page to make sure everything on the
parts list accompanied the kit. Once you are satisfied with the parts,
LETS GET BUILDING!