I am playing around with some old Crystal Mobilesound class T amps. The problem I am having is severely decreased FM Radio reception whenever the amps are powered up.
Most of this is EMI interference induced through the power and signal cables, however some of it is RFI coming from the shell of the amplifier itself.
The signal cable I am using is Monster Cable Interlink 401XLN (correctly oriented directional).
The signal source is a Clarion DXZ835MP headunit. All power wire is stinger, with 0/2 from the battery to a distro block (and vehicle ground) and 1/0 to the amplifiers.
I have already moved the antenna (and even replaced with a higher gain antenna). I have isolated the RCA lines with ground loop isolation to no effect. I have even run the Clarion on a 12 volt power source outside of the car (to a limited degree of success in slightly reduced interference).
The radio picks up every station I can think of untill the amps are powered on - after that, all I can recieve is full power local stations within 10 miles of the car.
Any suggestions will be appreciated.
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Sayar Kuchenski
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posted
Wrap the amps, RCA's and head unit in a load of aluminum foil Does it stidd do it with the vehical off? How far are the amps from the head unit?
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I am playing around with some old Crystal Mobilesound class T amps. The problem I am having is severely decreased FM Radio reception whenever the amps are powered up.
Most of this is EMI interference induced through the power and signal cables, however some of it is RFI coming from the shell of the amplifier itself.
Any suggestions will be appreciated.
Hi,
I have tried the following succesfully with my self-made tripath amplifier (for home use):
I suggest that you try connecting some small ceramic capacitors (try paralleling 10 nF + 100 pF, 100 volts) between all wires (yes, you must do this to RCA signal and signal ground) and amplifier enclosure. It would be even better if you could install a ferrite ring before the capacitors, but this is difficult to do.
If you possibly can, those caps would be best to install inside the amplifier, just next to connectors.
The interference you are experiencing is most likely conducted common mode interference type, and differential filtering is not going to be very effective against it.
With Best Regards, Janne
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posted
we noticed this a while ago, we were installing 5 crystal 600.2s whilst listening to a portable radio, first time we power the amps up >TSSSHHHHHHHHHH radio reception gone!
radio was about 1m away from the amps...
it didnt affect the radio of the car though.
Andy
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2004 : SS1-2 : 152.2dB 2005 : Street B : 152.9dB 2006 : Street MAX 1-2 : 158.5dB Posts: 727 | From: UK | Registered: Jul 2003
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