Sunday, May 25, 2014

Radiotron Designer's Handbook


Most of my knowledge in Audio DIY have been gleaned from the Radiotron 3rd Edition. The 4th Edition is just over the top of my head, but looks better sitting on my bookshelf ;)


Page 53, Chapter 8


Sunday, March 2, 2014

RC-12 Tube Manual

© 1934
All the tubes I am using in my Hi-Fi System were being manufactured by the time the RC-12 was published.

RCA phono from RC30
More info


But I also keep an RC30 copy! 

Thursday, February 27, 2014

Jensen Ultraflex redux

A few updates to the Jensen Ultraflex
Revised crossover + EQ/HF boost 
 The fixed resistor attenuator was inspired by the Jensen Duette crossover + recent knowledge gained in boosting frequencies above 7khz using an EQ network in my Altec 2-way XO experiments. Try it on your Heathkit SS1 or Eico HFS1 which AFAIK, used only a 2uf beeswax paper cap + L-pad.

Damping removed
paper in oil caps for
crossover and EQ
Happy Listening!

Saturday, February 15, 2014

de Forest 410 Mesh Plate




I've been feeling nostalgic lately especially after unearthing a box of prints and negatives which I've been scanning and uploading in the Arkiv.