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LL6702 is a hybrid transformer for line applications. It is constructed using a C-core and meets requirements for high isolation between windings. The LL6702 has an extremely low leakage inductance and thus a flat frequency response curve. This makes it easy to design the balancing network for a good transhybrid loss in the entire frequency range. Two LL6702 transformers are required to build a complete hybrid.

Technical Specification:

Turns ratio:1.5, 1.5: 1+1
Dimensions:47(l) × 31(w) × 15(h)
Spacing between pins:5.08mm (0.2")
Spacing between rows of pins:30.48mm (1.2")
Static resistance of primary (pins 1-4):50ohm
Static resistance of balance (pins 2-5):45ohm
Static resistance of each secondary (pins 6-7, 9-10):36ohm
Max DC current:60mA
Transhybrid loss (laboratory conditions):50dB, 10Hz-10kHz
Isolation between windings:2kV/4kV
Typical application:Telephone hybrid using two LL6702
Balancing network ZB:Select ZB for minimum crosstalk which occurs when ZB equals actual line impedance. In applications this is often accomplished with a combination of a potentiometer and a series of capacitors.
Line termination:If RI =RO, the termination impedance, ZT, as seen from the two-wire side is:
ZT (AC) =17ohm+RI +RD. Thus ZT is independent of ZB.
ZT (DC) =100ohm+RD. RD is an optional resistor used to reduce the line DC current.
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LUNDAHL LL6702 TRANSFORMER Analogue audio, for use in pairs to make hybrid transformer   Stock code: 23-141
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