[Lowfer] Noise R75 - rs232 from smpsu -

[Laurence KL7UK]

Anyone done any common mode noise mitigation from the RS232 port of the R75 Rx> - the noise coming up from the SMPSU/processor from the old Dell puter - cable is double screened - choking off using J (75) type has seen little improvement - this is my last hurdle to unimpeded remote rx on 137 - any pointers appreciated - everythings bonded and Ive tried the on/off earth tricks at various locations - 

 

Anyone had any success of powering a Dell D series from a non standard non switched PSU? (the noise goes away when the DC from the Black Dell brick is removed but it may also be partially screen/processor noise...)

 

with thanks

 

Laurence Kl7UK
 		 	   		  
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