So, I decided to get the cap kit from FM3zone for my FM3. Go that put in but still was chasing some hum. I did some wire twisting and redress. This is a kit built unit and some of the wiring to and from the volume switch area was poorly done. After all of this, I have lost my central stage. I get sound from the right and left speakers but when I tune to a public radio station, the announcers voice in the cengter of the sound stage is very faint. I guess the stereo processing is fouled up. Any troubleshooting suggestions I might try? TIA for any help. 6BL8 tube a problem now?
2 posters
Lost central stage on FM3
eickmewg- Posts : 103
Join date : 2014-08-29
Peter W.- Posts : 1351
Join date : 2016-08-07
Location : Melrose Park, PA
eickmewg wrote:So, I decided to get the cap kit from FM3zone for my FM3. Go that put in but still was chasing some hum. I did some wire twisting and redress. This is a kit built unit and some of the wiring to and from the volume switch area was poorly done. After all of this, I have lost my central stage. I get sound from the right and left speakers but when I tune to a public radio station, the announcers voice in the cengter of the sound stage is very faint. I guess the stereo processing is fouled up. Any troubleshooting suggestions I might try? TIA for any help. 6BL8 tube a problem now?
The first piece of advice I would give you is let it rest for 72 hours - do not even look at it! Then, go over every connection, joint and wire. Check *BOTH* ends, even ones you did not actually move or change. Look for cold joints, cracked wires, loose connections and such. Sometimes a cold-solder joint will last for years until it is disturbed - and as you don't think you touched it, you would have no reason to check it! Then:
a) Have you gone through the alignment procedure?
b) Do you have a means to test tubes? Bad tubes are unlikely (but not impossible) if it worked before.
c) Do you have another tuner to which you might compare actual results?
d) Did you get the PEC modules as well? It is key that the leads are where they should be and as short as practical.
Any time you do much of anything to an FM3, you should go through the entire alignment procedure.
Best of luck with it - these are very nice tuners.