Alert Monitor Schematic - 450 uhf Band

[hvfcadmin]

Hello all,

Does anyone have the service manual for the UHF Alert Monitors ????

I'm tring to figure out how to change the timming on the Relay output option for a Motorola Alert Monitor Reciever.
The Model is a M04CNB-1102B on 453.3250 Mhz
The unit has a small baord attached to the decoder board inside that i beleve resets the unit automatically after a nubmer of
seconds, My case it is ~ 8 sec. The unit is hooked up to a Federal Signal Horn system and works perfectly.. exept for the loud horn
stayes on for 8 seconds. The dispatcher usually starts dispatching 4 to 5 seconds after the second tone. I would like to change this to around 3 sec
so that the horn goes off before the dispather starts talking.

Some of the other stations have the same model, when an call comes in the alert light turns on, the horn sounds for three sec and then the unit resets itself, after
about 1 sec the dispatcher starts. I haven't looked inside them to see if there are any differences yet.
If you were to press the reset switch the horn will sound for 3 seconds. on units that i have seen with out this board in them, whenever the unit alerts the red light will stay on
untill you hit the reset switch. I have not tested to see if the relay inside is on the intire time, if this is the case then the horn would stay actice untill someone reset the unit.

Any help would be greatly apperciated.