I have a BLI QSI F7B unit that sometimes the sound works, and sometime does not. When the sound does work it sound's God Awful, creeks and pops when when I have the sound level to 50%. Sounds like dirty contact points. I have pulled the speaker plug and reinstalled with no change.
Would spraying down the whole board with CRC hurt the decoder board? This B unit has been a problem from the day I got it. Yet ABA unit with the same decoder has ran and sounded great from day 1?
Thanks for your time, Ken
I hate Rust
Probably not a good idea. It will mostly just make a mess.
Check the speaker, to make sure the cone isn;t torn, or that it hasn;t picked up a load of assorted metallic items from between the rails. Either one will cause the speaker to distort. If it's just collected a bunch of junk, you can remove that (careful not to damage the cone). If the cone is damaged, it's new speaker time.
It may be a blown amp, also look closely at the larger capacitors on the board and see if any are bulged or if there is any goo leaking out around the circuit board. Blown capacitors can make things like this happen too.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
rrinkerBlown capacitors can make things like this happen too.
Thanks Randy for the answer. If I where to spary down the board, it would be off the engine it self. Far as powe cap, I will take a look. Does seem odd if that is the problem that the sound would work at all?
Thanks for the answer again, Ken
Nope. Capacitors don't usually outright fail for some time. The go bad, and the value becomes different that what it's supposed to be, and that makes the circuit operate in a flakey manner. Plus, you could strip out everything associated witht he speaker and audio amplifier and the loco would still run, just no sound of course. So that sort of thing would have no effect on operation.
Could just be a loose wire to the speaker. That would make it crackley or not have any sound at times. Check that and the condition of the speaker first, that's more likely than blow caps.