ADS-B FDL-DB Dual Band Series
Installation Manual
Document No. 88552 Rev A
2-16
FFS Copyright © 2020 All rights reserved.
2.2.2 TC978 Controller
The TC978 Controller must be mounted rigidly in the aircraft panel. The Controller can be
mounted in the ultra-compact mounting or conventional 2.25 in [57mm] instrument cut-out
shown in SECTION 7.
Select a position in the panel that is away from any high external heat source. (The
TC978 is not a significant heat source itself).
Avoid sharp bends and placing the cables too near to the aircraft control cables.
If the TC978 is to be used as the annunciator for the required failure annunciations
(“ADS-B Fail”, “ADS-B GPS Fail”), the TC978 should be placed in the pilot’s
primary field of view.
If using a 2.25 in instrument cut-out, first clip the two mounting adapters to the Controller. The
Controller should then be mounted using the four LONG screws provided.
If using the FFS compact cutout, you do not need the mounting adapters. The Controller should
be mounted using the four SHORT screws provided. If alternate screws are required, please
note that the mounting thread in each case is 4-40.
Figure 3: TC978 Dimensions
2.3
Cooling Requirements
Failure to provide adequate cooling may lead to increased avionics maintenance
costs and may void the FFS Warranty.
The FDL-DB Series and TC978 meet all Technical Standard Order (TSO) requirements without
forced air cooling. While each individual unit does not require forced air cooling, the combined
heat load of several units operating in a typical avionics location may significantly degrade the
reliability of avionics if provisions for cooling are not incorporated in the initial installation.
