Lundahl Filament current choke, LL2772

Filament Current Choke LL2772

The LL2772is a 2 coil choke for tube/valve filament current filtering or other high current low voltage applications.The coil is wound using our standard high internal isolation technique with isolation foil between each copper layer. The core is an audio C-core of our own production.

Weight: 1.35 kg
Static resistance of each winding: 0.35 Ohm
Max current through each winding (10W heat dissipation): 3.8 A
Isolation between windings / between windings and core: 4 kV / 2 kV

LL2772 /3A Coils in series
Approx. Inductance: 80mH
Recommended DC current (1.25 T): 3 A
Saturating current (2.0 T): 4.8 A
Max. ripple voltage at rec. DC current (Ripple voltage is approx. 0.42 x input voltage): 52 V rms / 100 Hz

LL2772 /3A Coils in parallel
Approx. Inductance: 20mH
Recommended DC current (1.25 T): 6 A
Saturating current (2.0 T): 9.6 A
Max. ripple voltage at rec. DC current (Ripple voltage is approx. 0.42 x input voltage): 60 V rms / 100 Hz

LL2772 /5A Coils in series
Approx. Inductance: 50mH
Recommended DC current (1.25 T): 5 A
Saturating current (2.0 T): 8 A
Max. ripple voltage at rec. DC current (Ripple voltage is approx. 0.42 x input voltage): 52 V rms / 100 Hz

LL2772 /5A Coils in parallel
Approx. Inductance: 12mH
Recommended DC current (1.25 T): 10 A
Saturating current (2.0 T): 16 A
Max. ripple voltage at rec. DC current (Ripple voltage is approx. 0.42 x input voltage): 60 V rms / 100 Hz

Note! The LL2772 can also be used in choke input power supplies.