Internal Modifications; Turning On/Off Line Out 1 (2) In Conjunction With Zone 1 (2) Selector Switch; Turning The Power Off To Disable Broadcast With Emrgency Control Activation; Convert Tel Paging Input Into Transformer-Balanced Type - Toa A-1803 Operating Instructions Manual

14. INTERNAL MODIFICATIONS

Leave the modifications described here to a qualified service technician only.
Please consult your TOA dealer.
[Upper view without case]
Control circuit board
Main circuit board

14.1. Turning On/Off LINE OUT 1 (2) in conjunction with ZONE 1 (2) Selector Switch

• To interlock LINE OUT 1 with ZONE 1 switch, install the
SJP100 jumper to "ON" position.
• To interlock LINE OUT 2 with ZONE 2 switch, install the
SJP101 jumper to "ON" position.

14.2. Turning the Power Off to Disable Broadcast with EMRGENCY Control Activation

Install the SJP102 jumper to "OFF" position.

14.3. Convert TEL PAGING Input into Transformer-Balanced Type

Step 1. Cut the jumpers SJP400 and SJP401.
Note: Treat the cut jumper pieces, especially SJP400's
pieces, so that they will not touch the transformer
case to be installed in the next step.
Step 2. Install and solder the optional IT-453A Input Transformer in place of "T400" indication on the Control
circuit board.
SJP400 and SJP401 "T400" for mounting the IT-453A
Factory-preset position
SJP102 (EMERGENCY)
SJP100 (ZONE 1)
SJP101 (ZONE 2)
Jumper
OFF
ON
Factory-preset position
SJP102 (EMERGENCY)
Jumper
ON OFF
SJP401
Rear panel
SJP100 (ZONE 1)
SJP101 (ZONE 2)
OFF
ON
ON OFF
SJP400
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