20-10-2014, 07:47 PM
The high HT at switch on shouldn't be a problem for the valves John, just make sure any HT related capacitors are rated enough, you could leave the thermistor in circuit as it will limit the surge current through the rectifier and res/filter caps at switch on, you can always add a series R if the working HT is too high with the new silicon rectifier fitted.
The preferred thermistor for rectifier surge limiting in the old radios used to be the Brimistor CZ10:
http://electrojumble.org.uk/DATA/STC_Bri..._Types.pdf
Lawrence.
The preferred thermistor for rectifier surge limiting in the old radios used to be the Brimistor CZ10:
http://electrojumble.org.uk/DATA/STC_Bri..._Types.pdf
Lawrence.
