Thursday, May 3, 2012
Rationalizing a 1960 Vibrolux amp
This amp is a May, 1960 5F11 Vibrolux that is in beautiful cosmetic shape but which has been hacked a bit. It's not ready for a clean bill of health yet but the patient did not die on the operating table. It has the original output transformer but the power transformer has been changed for something or other, and a 12" ceramic speaker has been installed in place of the original Jensen P10R.
This is but a preliminary report with pics to satisfy some catcalls from the audience.
After redoing the transformer wiring and removing a couple of feet of excess wiring, it needed an adjustable bias and some oscillator capacitors to get the vibrato working at its best. The sweet spot seemed like about 23 ma per side, and it works better if you control it with a foot switch.