Showing posts with label black noisies. Show all posts
Showing posts with label black noisies. Show all posts

24 May 2010

Worse than the H1N1... ceramic filter pandemic

Well, it could be a false alarm (pun intended) but lately I have been getting more and more rigs for repairs, and from diferent manufacturers, with bad Toko black ceramic filters (6 and 9 kHz by now)

I have fixed three rigs in the last few weeks with this problem, two Yaesu FT-897 and one Kenwood TS-2000. Symptoms could range from lower sensitivity, to cracking noises and, usually, you have both. There is also an interesting effect, at least on FT-897s, which is that they receive in DSB instead of SSB when filter fails.

I have opened one filter and it had some greenish looking residue on it, so I guess sealing had failed and moisture did the dirty job.

I would be interested in hearing other people experiences with those small "BLACK NOISIES" (*) (remember you saw it first here, (c) EB5AGV ;-) )

Best regards,

JOSE

(*) the equivalent to "BLACK BEAUTIES" caps in old boatanchors!