Lesson 2/Learning Event 2
TM 11-468 Extract has the procedure described to perform a continuity check of the TA-236/FT
using a test set, TS-190/U, which is a receiver/test pick. When using the TS-190, the telephone must be
connected to a telephone line for power. If connected to a dial central office line, dial tone will be heard
while performing a continuity check. If connected to a common battery (CB) switchboard line, power
"clicks" will be heard. Although the TM extract describes the procedure used, a further explanation is
deemed necessary. Each circuit has two ends and you block the circuit to divide it in half. When you
are connected to L2 terminal and go to the first check point, you are actually checking L1 side to that
point. If continuity is heard, your L1 side is good, if not, continue on to the next point. You must
change ends and continue checking other side of the line.
A multimeter may be used instead of a TS-190 to make continuity checks. If a multimeter is
used, a resistance reading will indicate continuity. It is not necessary to have the telephone connected to
a telephone line since the multimeter has its own power source.
The troubleshooting chart in the TM extract has a listing of the most common symptoms,
problems, and corrective actions needed to restore the TA-236/FT to operational order.
Learning Event 2:
PERFORM FINAL TESTING OF THE TA-236/FT
Once the problem has been repaired, a final test must be conducted before returning the
instrument to the owning unit.
The final test of the TA-236/FT is conducting one last visual inspection of the telephone set and
performing an operation check by checking outgoing and incoming signaling, transmission, and