Harris eCDi, Technical Manual

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G-2 888-2517-001 1/3/05
WARNING: Disconnect primary power prior to servicing.
eCDi ™
Appendix G Platinum TV Monitor
G.2 Upgrading Early Monitor Boards
If your Platinum Monitor Board was not factory fitted with SENTRY™ firmware, you
will need to install new firmware PROM's (U17 and U18) in the transmitter. Make sure
you have the correct EPROMs. They should be labelled:
HARRIS CORP 1993 HARRIS CORP 1993
917 2235 003 917 2235 003
VHFS004SC U17 VHFS004SC U18
The last line of the label on each PROM gives the firmware revision level and the IC
socket location number on the monitor board.
If the markings on the existing U17 and U18 EPROMs have firmware revision number
E.0.12 or lower, the Monitor Board will also require 2 new memory chips (U19 and
U20), and a replacement PAL (U8) for address decoding in addition to the new U17 and
U18. These added upgrade components, along with the required jumpers, are included
with the eCDi installation kit for Platinum Analog TV Transmitters.
IMPORTANT:
Transmitters requiring replacement of U17 and U18, will also require two 6 dB
50 ohm attenuators in order to correct the directional coupler sensitivities.
G.2.1 Tools
Upgrading the transmitter monitor board to SENTRY™ firmware will require that you
remove two PROMs, U17 and U18, from the monitor PC board and replace them with
new SENTRY™ PROMs. (Revision E.0.12 or earlier systems will require replacement
of some other IC's as well.) You should have suitable tools on hand to use in extracting
the existing IC's. To avoid possible damage due to static electricity, you should have
and use a properly grounded wrist strap during the handling of these PROMs.
G.2.2 Required Installation Time
The actual installation time can be quite short, but you will be working in an area of the
transmitter which may be unfamiliar, so it is advisable to allow a few hours'
unencumbered off-air time to complete the installation.