2. analog
  3. 1258958197

FM frequencies cut out by CD player

How can these two phenomenon be related?

When I am listening to my Etude tuner and then turn on my Rega CD player, the stations from about 98.1 or so will be cut out completely, as if you are flipping a switch on a tape monitor. The lower frequencies become somewhat fuzzy but still come through. Both components are feeding into an Audible Illusions pre-amp. Also, when the pre-amp is switched to the CD while the tuner is on and you are between discs, you can very faintly hear the music from the tuner through the speakers.

Has anyone else ever heard anything like this? Any ideas??? (The cd player is mounted on a shelf about eight inches above the tuner and the pre-amp is about eight inches below the tuner.)
128x128wynnosu

Showing 2 responses by mlsstl

mlsstl
1,378 posts
 
It would appear from your description that the CD player is emitting RFI (radio frequency interference) in the same band the FM stations are using. That's not unusual. Digital devices can be pretty noisy in the radio spectrum.

Are you using an external antenna or the one built into the tuner?

If you are using the tuner's internal antenna, one solution might be to use an external antenna located away from your equipment stand and connect the antenna to the tuner with TV coax cable. (The antenna doesn't have to be outside. 5 or 10 feet from the CD player would likely be more than adequate.)

Tuners are designed to reject a certain amount of noise at the same frequency as the broadcast frequency but there is a limit.

If the external antenna doesn't help, your only other likely solution is to place the tuner itself away from the CD player.
mlsstl
1,378 posts
 
I wouldn't think the problem is preamp input crosstalk. The OP states that the problem is worse above 98.1 MHz on the FM dial and less of a problem below.

Crosstalk would affect all the station frequencies equally since it would be occurring at the analog input stage of the preamp.
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