LL1691D: Lundahl Output Transformer

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The Lundahl LL1691D is a dual-coil single-C-core tube amplifier output transformer for 10K: 4R & 16R impedance ratio available in PP and SE versions. Suits 845 valves.

The transformers are highly sectioned with harmonically sized sections, which results in a minimum leakage inductance. Combined with a low capacitance coil winding technique, this results in a wide frequency range. The transformers have a special audio C-core of our Lundhal`s production, which is gapped for the desired DC current. This would depend on the current draw of the output valves. The transformers are of an open frame type and are suitable for mounting inside an amplifier housing.

The LL1691D is available in 2 versions. (The air-gap is adjusted during manufacture to suit)

  • Push-Pull
  • 70mA Single-ended

(N.B. The purpose of the airgap is to accept the DC current of the output valve without saturating the core, leaving enough headroom for the sound signal)

Depending on how the winding sections of the transformers are wired together via the exposed solder pins, the constructor can adjust the following primary and secondary impedances.

Primary impedance: Secondary impedance

  • 10K: 4R or 16R

Overall dimensions including pins - 148mm x 103mm x 90mm

PRICE (1 off)
£286.74 +vat +p&p

Non-Stock Item - Please allow 4-6 weeks for dispatch

PDF datasheet

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