[600MRG] [rsgb_lf_group] Receiver protection

[David G0MRF]

 Hi Paul


I'm sure you will get many good ideas from the group.
I took the view that my preamp protected the receiver....and the preamp was expendable. - Also the max output from the preamp was not sufficient to damage the receiver.


Even so....After using it for a while, I decided that a little more protection was called for, so I placed a small relay (about 1/2 inch square) to short the input to the preamp to ground when the system was in 'transmit'




73


David

 

 

-----Original Message-----
From: N1BUG paul at n1bug.com [rsgb_lf_group] <rsgb_lf_group at yahoogroups.co.uk>
To: rsgb_lf_group <rsgb_lf_group at blacksheep.org>; rsgb_lf_group <rsgb_lf_group at yahoogroups.co.uk>; Discussion of the Lowfer (US, European, & UK) and MedFer bands <lowfer at mailman.qth.net>; 600MRG <600MRG at mailman.qth.net>
Sent: Tue, 10 Jul 2018 12:05
Subject: [rsgb_lf_group] Receiver protection



  
    
                  
Does anyone have ideas for receiver front end protection at LF and
MF? I am worried about my TX signal damaging receivers.

Of course the best idea is to disconnect the RX antenna from the
receiver while transmitting. Any good solution while leaving it
connected?

Now I have a pair of back to back 1N4148 diodes across the receiver
front end but I don't think this offers real protection because they
allow too high voltage before conducting. Also there is a preamp
after the didoes which can bring the RF to dangerous levels!
(Somehow nothing was damaged during last winter operating this way... :)

73,
Paul N1BUG


    
             
__._,_.___
                     
 
    
        
        Posted by: N1BUG <paul at n1bug.com>        
     
    
 
    
      
        
          
                          Reply via web post                      
          
•
          
                           Reply to sender                      
          
•
          
                          Reply to group                      
          
•
          
            Start a new topic          
          
•
          
                            Messages in this topic                (1)                      
        
      
    
         
    VISIT YOUR GROUP                                                           
  
  
 • Privacy • Unsubscribe • Terms of Use 

  
        
     
              
      
SPONSORED LINKS
      
        
                                                    
        
                                                    
        
                                                    
      
    
        
     
.
   
 
__,_._,___
  

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/600mrg/attachments/20180710/a7426112/attachment.html>