  | 
				Matronics Email Lists Web Forum Interface to the Matronics Email Lists   
				 | 
			 
		 
		 
	
		| View previous topic :: View next topic   | 
	 
	
	
		| Author | 
		Message | 
	 
	
		speedy11
 
 
  Joined: 29 Jun 2015 Posts: 62 Location: Port Orange, FL
  | 
		
			
				 Posted: Sun Feb 12, 2017 9:17 pm    Post subject: Icom antenna junction box | 
				     | 
			 
			
				
  | 
			 
			
				Dean,
  
  I was one of those who was wondering if my "SL30 failure" might have been caused by the Icom junction box (I have mine wired like yours) but I just got word from the radio shop that the problem exists in the SL30.  The radio is on the way to Garmin for a $500 repair.  
  So, at this point I cannot say the Icom unit is causing any issue.
  
  Stan Sutterfield
  RV-8A
  Daytona Beach, FL
  
   
      	  | Quote: | 	 		  Someone was asking on this forum about issues with the Icom antenna junction
   box installed in their plane.  I  put in one of those in between my SL-30
   Nav/Com and my belly antenna on the RV-6A. I've had a lot of scratchy and
   not so great transmissions/reception on that Radio.  I didn't think that
   maybe if would be that junction box.  I like the idea because it makes it
   easy to plug in my hand held and use my outside antenna. But I've never had
   to do that so if the junction box is causing crappy tx/Rx on that radio I'll
   take it out of the loop. I know the SL-30 is a great radio so this has
   puzzled me since I finished the RV.  Did whomever it was figure out whether
   the Icom junction box was causing radio Tx/Rx problems or not?  Does the
   junction box need to be removed from the loop or is there some I can do to
   fix it?  
   
   
   Thanks
   
   Dean Psiropoulos
   RV-6A N197DM
   Tarpon Sprgs, FL | 	 
 
 
  |  | - The Matronics AeroElectric-List Email Forum - |  |   |  Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
 
  http://www.matronics.com/Navigator?AeroElectric-List |  
  |  
 
 
 
 
  | 
			 
		  | 
	 
	
		| Back to top | 
		 | 
	 
	
		  | 
	 
	
		fly4grins(at)gmail.com Guest
 
 
 
 
 
  | 
		
			
				 Posted: Mon Feb 13, 2017 4:05 am    Post subject: Icom antenna junction box | 
				     | 
			 
			
				
  | 
			 
			
				Lo those many days ago that I tinkered with radios a little, keying the mic without a load connected would likely fry the transmitter.  Is it possible that a crappy connection internal to the splitter box could be damaging the current crop of radios over time?
 
  |  | - The Matronics AeroElectric-List Email Forum - |  |   |  Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
 
  http://www.matronics.com/Navigator?AeroElectric-List |  
  |  
 
 
 
 
  | 
			 
		  | 
	 
	
		| Back to top | 
		 | 
	 
	
		  | 
	 
	
		nuckolls.bob(at)aeroelect Guest
 
 
 
 
 
  | 
		
			
				 Posted: Mon Feb 13, 2017 5:51 am    Post subject: Icom antenna junction box | 
				     | 
			 
			
				
  | 
			 
			
				At 06:02 AM 2/13/2017, you wrote:
   	  | Quote: | 	 		  | Lo those many days ago that I tinkered with radios a little, keying the mic without a load connected would likely fry the transmitter.  Is it possible that a crappy connection internal to the splitter box could be damaging the current crop of radios over time? | 	  
    An excellent notion to ponder . . . the root
    concern about the Icom Antenna j-box is the
    quality of the normally-closed switch contacts
    that automatically disconnect the panel mount
    radio from the feedline when the hand-held
    coax is plugged in.
 
    A secondary concern is loss of feedline integrity
    with the inclusion of simple, single strands of
    wire used to make up connections within the box.
    Without putting one on the test bench I don't
    KNOW the degree of upset but we know that it's not
    zero.
 
    The very first all solid state transceiver I
    brushed elbows with was installed in the T-41
    trainers we built for the USAF back in the 1967
    time frame. These were C-172s with engines out
    of the C-337 (0-360, 210 hp). Always flown as
    a two-place a/c (but with a compliment of heavier
    military avionics) this made for a VERY snappy
    C-172.
 
    Intended for use at the USAF Academy in Colorado,
    the extra horsepower was very welcomed for
    student training in the rarified air of the
    high plains. 
 
    Part of the standard equipment was a little
    solid state, panel mount style transceiver
    mounted back in the tail and crystals installed
    only for 121.5 Mhz only.  I'd never heard of
    the brand before and now don't recall it . . .
    but I do recall that several radios were toasted
    during production test and trouble shooting phases
    due to transmission into open feedlines.
 
    This was long before the manufacturers figured
    out how to built an SWR detection system into the
    radio to effect automatic shutdown of the transmitter
    when SWR was too high. Further, the early VHF    
    power transistors were rather intolerant of hi SWR
    to begin with.
 
    Modern radios are probably the much more robust,
    MOS-FET output stages and will include auto-shutdown
    for high SWR. However, a dodgy switch in the Icom
    antenna j-box could very ell contribute to noisy
    rformance of the radio.
 
  
    Bob . . .
 
  |  | - The Matronics AeroElectric-List Email Forum - |  |   |  Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
 
  http://www.matronics.com/Navigator?AeroElectric-List |  
  |  
 
 
 
 
  | 
			 
		  | 
	 
	
		| Back to top | 
		 | 
	 
	
		  | 
	 
	
		fly4grins(at)gmail.com Guest
 
 
 
 
 
  | 
		
			
				 Posted: Tue Feb 14, 2017 3:45 am    Post subject: Icom antenna junction box | 
				     | 
			 
			
				
  | 
			 
			
				 >   Without putting one on the test bench I don't >  KNOW the degree of upset but we know that it's not >  zero.
 
 Well now, as it happens, I've got one in a dusty box somewhere.  Knowing how bored you tend to get *grin* I'd be willing to send it your way if you are interested.
 
  |  | - The Matronics AeroElectric-List Email Forum - |  |   |  Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
 
  http://www.matronics.com/Navigator?AeroElectric-List |  
  |  
 
 
 
 
  | 
			 
		  | 
	 
	
		| Back to top | 
		 | 
	 
	
		  | 
	 
	
		nuckolls.bob(at)aeroelect Guest
 
 
 
 
 
  | 
		
			
				 Posted: Tue Feb 14, 2017 11:07 am    Post subject: Icom antenna junction box | 
				     | 
			 
			
				
  | 
			 
			
				At 05:42 AM 2/14/2017, you wrote:
   	  | Quote: | 	 		  Â >Â  Â Without putting one on the test bench I don't
  Â > Â KNOW the degree of upset but we know that it's not
  Â > Â zero.
 
  Well now, as it happens, I've got one in a dusty box somewhere.  Knowing how bored you tend to get *grin* I'd be willing to send it your way if you are interested. | 	  
    Sure. I'd like that . . .
 
    The one I photographed was new out of the box
    and did function well. Having one with some
    effects of aging would be an interesting thing
    to ponder.
 
  
  
    Bob . . .
 
  |  | - The Matronics AeroElectric-List Email Forum - |  |   |  Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
 
  http://www.matronics.com/Navigator?AeroElectric-List |  
  |  
 
 
 
 
  | 
			 
		  | 
	 
	
		| Back to top | 
		 | 
	 
	
		  | 
	 
	
		 | 
	 
 
  
	 
	    
	   | 
	
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You cannot attach files in this forum You can download files in this forum
  | 
   
 
  
Powered by phpBB © 2001, 2005 phpBB Group
  
		 |