(!!!!) (Best Value Quad) 56 National Union rebranded Western Electronics NOS 1940's (5.5/5.5/5.6/5.9ma) (matched quad)

1 matched quad) 56 National Union rebranded Western Electronics NOS 1940's

1 tube) 5.5ma Gm=1400

1 tube) 5.5ma Gm=1500

1 tube) 5.6ma Gm=1500

1 tube) 5.9ma Gm=1500

Matched on Amplitrex

Vplate=250V

Vgrid=-13.5V

Good Ma range = 4.5 - 5ma

Good Gm range = 1300-1400

(76=Type 56 with a 6.3V Filament and also is similar to type 37)

UX-5 pin socket
 

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