888-2406-002
4-49
WARNING: Disconnect primary power prior to servicing.
Overall System Theory
4.7.6.1.1.4 CONTACTOR_ON(BAR), K4-4
The signal at K4-4 is called CONTACTOR_ON(BAR) and ties to several places,
U33-12, U30-12, and U30-10. This signal is low when K4 is in the SET position
and the contactor is engaged.
a.
The CONTACTOR_ON(BAR) signal at U33-12 is only used during Life
Support Mode. Whenever the transmitter is on, K4-4 will be low, which holds
U33-12 low. If the Master Controller has failed the MSTR_NORMAL 1 sig-
nal will also be low. This makes the output at U33-11 and the input to U32-1
low. Once the initial 100mSec turn on pulse from U4-10 is gone, the CLR
input to U4 will also go low, holding the Q output low whether the ON button
is pressed or not. This prevents U8-10 from generating a 3 second mute com-
mand for no reason, since the Master Controller is not working and cannot be
initialized (if the Master was working, MSTR_NORMAL 1 at U33-13 would
be high removing the clear from U4-13). The transmitter must first be turned
off, then turned back on to try to initialize the system. Once the transmitter is
turned off, a turn on pulse can be generated since K4-4 will be high when the
contactor is disengaged. This removes the clear from U4 allowing the trans-
mitter to turn on. In summary, the signal at U33-12,
CONTACTOR_ON(BAR), will not allow a second turn on pulse to be deliv-
ered while the transmitter is still running and in Life Support Mode.
b.
The CONTACTOR_ON(BAR) signal at U30-12 is used to disable the power
supply when the contactor is turned off. The signal is high when the transmit-
ter is off and low when turned on. The other input, U30-13 comes from the
Master Controller, SUPPLY_DISABLE, which will pass through to U6-8 as
long as the Master Controller is operating normally. When the PS DISABLE
signal at U30-11 goes high, the power supplies will be shut off via the PS
Controller.
c.
U30-10 ties the CONTACTOR_ON(BAR) signal into the SYSTEM_MUTE
line, which will mute the exciter and IPA when the contactor is off.
4.7.6.1.1.5 Remote Low Power ON Command
This command should only be used during Life Support Mode and is therefore
discussed later.
4.7.6.1.2 Transmitter Turn OFF
Whenever the OFF button on the front panel is pressed, the Master Controller sends
a high TX_OFF command to J1-A53 on the Life Support Board. This is tied to
AND gate U25-12. When the Master Controller is working, MSTR_NORMAL1 at
U25-13 will be high and U25-11 will go high. This high will pass through to U31-
11, U33-6 and inverted at U16-10 before reaching the RESET input of K4. When
K4 is RESET, the AC mains contactor will de-energize, shutting off the transmitter.
The CONTACTOR_ON(BAR) signal at K4-4 will go high, applying a
Summary of Contents for Platinum Z2 CD
Page 4: ...888 2406 002 WARNING Disconnect primary power prior to servicing ...
Page 6: ...888 2406 002 WARNING Disconnect primary power prior to servicing ...
Page 8: ...888 2406 002 WARNING Disconnect primary power prior to servicing ...
Page 10: ...888 2406 002 WARNING Disconnect primary power prior to servicing ...
Page 70: ...3 14 888 2406 002 WARNING Disconnect primary power prior to servicing Operator Guide ...
Page 130: ...4 60 888 2406 002 WARNING Disconnect primary power prior to servicing Overall System Theory ...
Page 194: ...6 38 888 2406 002 WARNING Disconnect primary power prior to servicing Troubleshooting ...
Page 196: ...7 2 888 2406 002 WARNING Disconnect primary power prior to servicing Parts List ...