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Old 10-16-2010, 10:58 AM
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Einar72 Einar72 is offline
Chasin roundies since '79
 
Join Date: Jan 2006
Location: Federal Way, Washington
Posts: 936
I'd like to hear if any of you that used wirewound resistors had trouble with the CRT filament getting light-bulb bright at power-up. About 25 years ago I used a mix of Clarostat vitreous enamel units plus a couple of ceramic ones pulled from a Heathkit AA-22. Seems the phrase "controlled heater warm-up time" was not applicable to the 7JP4, with the advent of specially-engineered series-string tubes years in the future...
I think the ballast was designed to absorb the current surge and protect the other heaters from doing the same. Great to hear about the Amperite relacement, I think that's a cheap price compared to replacing a 7JP4 with an open heater.
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