Thread: Heater voltages
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Old 12-23-2025, 08:27 PM
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bandersen bandersen is offline
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I made a video where I analyze the ballast and do the math. The ballast resistance is not high enough even for 117 vac line voltage.

Also the tube lineup did change over time, but for the most common TS-4J or TS-18, the two strings are not equal.

They should be about 130 and 150 ohms.
https://youtu.be/vuYYx8AXbFc?si=oAIt7oyLNbKI20Wj&t=3751
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