Eliminates 80% of the parasites From the built-in HP to our dear (yes dear) TX or RX,  
This home-made model, treated acoustically  
(ie stuffed with rags, glass wool or foam)  
it will replace the plastic case of your favorite brand.  
the listening comfort of HP is endowed with some well designed filters.  
(Passive filters, with attenuation of the BF level will scream the purists) HI!  
but what does it matter since the volume / AF gain knob is there to compensate eventually.  
it is an important link in our chain of reception:  
The station HP described here, has been in service in my station for a long time,  
to my great satisfaction, the filters, if they do not remove the QRM of all orders,  
attenuate it substantially according to the part of the spectrum where it is rampant.  
But above all :  
when listening long, they allow to change from time to time the 'color of sound',  
thus reducing auditory fatigue.  
In addition, a headphone output can also benefit from corrections  
(there, the High cut filter is wonderful)  
a line output without correction is available if you need BF for the FAX, RTTY ...  
Wind the cord from the TX on a ferrite stick (about ten turns)  
Dame HF is always on the lookout for a bad shot!  
The sound comfort and all the possibilities of cutting the sound to his ear,  
you will quickly realize that this is one of the most interesting accessories  
of your station that you have ever made.