RD112-100 Capacitor Replacement

RD112

20uf 25VDC - CDE Mallory 22uf 50VDC
20uf 50VDC - CDE Mallory 22uf 50VDC
150uf 3VDC - mystery cap...replaceed with Mallory original 150uf 50VDC
150uf 50VDC - Sprague Atom 150uf 50VDC
400uf 25VDC - Sprague Atom 400uf 25VDC
100uf 450VDC - Illinois Capacitor 100uf 450VDC

[img]https://i.imgur.com/iFigqbV.jpg[/img]
[img]https://i.imgur.com/JrBA5kC.jpg[/img]
[img]https://i.imgur.com/h8da8Qp.jpg[/img]
[img]https://i.imgur.com/Uc5pNaR.jpg[/img]

I also touched up some poor solder joints.

The aim was to reduced the white noise (hiss) when the Gain is anywhere above 2. Sadly, no change in the background hiss...but I am pretty confident in the new electrolytics going forward.

Full Name
Rob Flindall
Music Man Equipment
112RD-100 with EVM speaker, built 1981

Member for

10 years 3 months
Profile picture for user RD112

RD112 Mon, 06/25/2018 - 20:32

The small 150uf 6.3VDC capacitor arrived...don't know why it came separate...anyway...it all fits in nicely now.
the final cap is a Sprague Vishay AS series. I still don't see this small capacitor in the 2100 GD-2A schematic...but it must serve a purpose.

Images