LL1693: Lundahl Output Transformer

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LL1693: Lundahl Output Transformer

The LL1693 is a high-power tube output transformer primarily for low-impedance high-power tubes. The primary impedance is 600R, 1K or 2K3, and the secondary impedances are 4R, 8R, or 16R, depending on how you wire them up. There are options for circuit topology, which you select when you purchase.

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 LL1693 is available in 2 versions. (The air-gap is adjusted during manufacture to suit)

  • Push-Pull
  • 230mA 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)

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

Primary impedance: Secondary impedance

  • 2K3: 8R or 16R
  • 1K: 4R, 8R or 16R
  • 600R: 4R, 8R or 16R

Overall dimensions including pins - 140mm x 100mm x 100mm

PRICE (1 off)
£287.74 +vat +p&p

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

PDF datasheet

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