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

 Check out my 516F2 mods here:
>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

> 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,
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