Re: {Collins} 516F-2 Re-Cap Discovery



 Al,
 
 Check out my 516F2 mods here:
 
http://www.crompton.com/hamradio/collins/index.html
 
>From my Photos it looks like I just changed the diode and left the other stock bias components intact. I see the 100 ohm resistor there. It works fine the way I have it. You might also be interested in some of the other mods I made to the supply. I am very happy with its performance. 
 
73 Doug
WA3DSP
http://www.crompton.com/hamradio

 
> Date: Sat, 3 Aug 2013 15:54:52 -0700
> From: awaschka@xxxxxxxxxxxxx
> Subject: {Collins} 516F-2 Re-Cap Discovery
> CC: collins@xxxxxxxxxxxxx
> To: doug@xxxxxxxxxxxx
> 
> I'm recapping a WE 516F-2 that I got with a WE KWM2-A several years ago and the bias network doesn't match the schematic in the manual on the CCA web site (1974 version).  The 5R4 has been replaced with a solid state unit, but my major questions are in the area of the bias network.
>  
> Starting from the transformer bias winding, the 100 ohm resistor is missing, the rectifier is a 1N1490, and the resistor string is 2700 ohms to a 2500 ohm pot and a 3300 ohm to ground.  Is sthis some kind of an update due to replacing the old Sarkes Tarzian 50 with a 1N1490?  I would have thought that the 100 ohm would be increased to reflect the lower resistance of a more modern diode.  I see no benefit in cutting the resistor values, in fact, it ups the bias network dissipation by nearly a factor of 4.  It is clearly not original based on the poor workmanship of soldering the parts.
>  
> Can someone advise me on the best approach to rework this?  Values as existing, or manual values?
>  
> Thanks,
>  
> AL K5TAN
> _______________________________________________
> SHARE THE FUN: JOIN THE COLLINS COLLECTORS ASSOCIATION TODAY !
> http://www.collinsradio.org/?page_id=37
> 
>  NETS: Tues & Thur: 3.805 MHz-2000 Central + Fri: 3.895 MHz-2000 Pacific
>   SUNDAYS: 14.263 MHz-2000 UTC  +  AM Net: 29.050 MHz-1200 Central
>   1st Wednesday AM Net 3.880 MHz-2000 local (ET, CT, MT, PT)
> 
> The Collins Reflector reserves the right to refuse access to anyone.
> 
> LIST HELP?  ADMIN EMAIL:  collins-owner@xxxxxxxxxxxxx
> This ONLY goes to the list admins and does not post to the group!
> 
> *** You are subscribed to Collins as doug@xxxxxxxxxxxx. If you wish to unsubscribe, or modify your preferences please visit http://mailman.listserve.com/listmanager/options/collins/doug%40crompton.com or to learn more about our list visit http://mailman.listserve.com/listmanager/listinfo/collins ***
> 
 		 	   		  



This archive was generated by a fusion of Pipermail (Mailman edition) and MHonArc.