Filament Chokes
B & W Filament Choke
40 µH / 30 amp
(ICH) FC25A
40 µH bi-filar 10 gauge enameled wound on a 7-1/2" x 1/2" ferrite rod. Usable 1.8 - 30 MHz. Easily handles, for example, two 3-500Z tubes. We purchased the last remaining stock from B&W. Includes mounting hardware.
$35 each
Collins 30L-1
Filament Choke 7.5 µH
(COL) 240-1244-000
Made for use with four 811A tubes in parallel. Compact size (1-1/4" x 2" x 2-1/2" high). 15 amps.
$85 each