En elegant och enkel idé för att öka drifts säkerheten!
This project was based on a short, 3/4 page sidebar article on page 18 of the August, 1991 issue of Monitoring Times. It was part of an article on old radios and restoration, entitled "The Fascination of Vintage Radio" by Linton G. Robertson. He claimed that "with this simple device, tube life can be extended at least 300 percent, and the rest of your set's touchier components will be treated to a nice slow wake-up as well, thus preserving their life, too." The article says that it takes the thermistor about 15 seconds or so to heat up and increase the set's voltage from the starting 40 to 60 volts up to full voltage. There will still be some small voltage drop across the thermistor, and the set's voltage won't be quite the full line voltage. He says this size thermistor is good for radios from about 40 to 120 watts.