Funny, I rec'd a FA-2/NW-2 (part # 885-E004) Tru Blast II horn on April 8. Installed it yesterday in my post war Lionel NW-2. I have the same problem---as the loco moves around, you barely hear the horn. The bell is slightly louder, but nowhere near the volume my other Williams horns make. I also tried to adjust the volume control, but nothing changed. Here I thought I did something when I installed it, but now I don't think so...
To Earl in VA. Your horn unit does have the external diode(? or whatever) connected to the main sound board with a red, black and orange wire, correct.
To Earl in VA. Your horn unit does have the external diode(? or whatever) connected to the main sound board with a red, black and orange wire, correct.