Model: IC -275 Bulletin: B1001 Subject: If the IC amplifier oscillates when the noise blanker is turned on and the FL-83 CW narrow filter is installed 1. Remove the covers to gain access to the main circuit board. 2. Remove R354 (22K) from the main circuit board and replace it with a 10K (ICOM P/N 915-01113) resistor. 3. Re-install the main circuit board and replace the covers on The radio.