Avionics FAQ

Yes, the KTR-953 receiver/exciter and KAC-952 antenna coupler can be mounted in different locations but problems may be encountered as a result. When the KTR-953 and KAC-952 are mounted in different locations, transmitter distortion and common mode rejection can be encountered within the system. Other symptoms might include:
  • Display flashing intermittently when the user tries to tune the HF
  • Audio distorted when transmitting on AM or SSB
  • Output power low and varies when measured with wattmeter
If the KTR-953 and KAC-952 must be mounted more than 3 feet apart, then there are 3 Service Bulletins that should be incorporated into these units.
  • KTR-953 Service Bulletin 8 is effective for units S/N 29974 and below. This SB consists of removing several parts, install some wires, and mounting an feedback board into the unit
  • KAC-952 Service Bulletin 9 is effective for units S/N 14332 and below or units with an older control board. This SB consists of make changes to the ALC circuit.
  • KAC-952 Service Bulletin 10 is effective for units S/N 14884 and below or units with an older control board. This SB is a continuation of the modifications performed on KAC-952 SB 9 and consists of replacing several resistors and capacitors in the unit.
All 3 service bulletins are recommended for this installation condition. All 3 service bulletins are interdependent of each other and must all be installed for the system to function properly under these circumstances.

For more information on these modifications, please contact an SEA service representative today.