15 V FOR VTVM

Posted on Feb 5, 2014

Simple rectifier circuit replaces battery in vacuum-tube voltmeter. Provides good regulation and eliminates need for frequent battery replacement. Remove battery before using supply. AC source can be 6. 3-V secondary of filament transformer or terminals of 6. 3-V pilot lamp in any AC equipment. -P. Alexander, Battery Replacement Circuit for VTVM, QST

Click here to download the full size of the above Circuit.

, Jan. 1976, p 42-43.

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