Transformer 9-0-9V 20VA

The Transformer 9-0-9V 20VA is a step-down transformer with a centre-tapped secondary that provides 9 V AC either side of the centre tap and 18 V AC between the outer wires. At 20 VA it suits medium-sized projects such as preamplifiers, control boards and regulated supplies that draw around 1 A.

Transformer 9-0-9V 20VA Specifications

• Secondary voltage: 9-0-9 V AC, centre-tapped (18 V AC end to end)
• Power rating: 20 VA
• Secondary current: about 1.1 A across the full 18 V winding (20 VA ÷ 18 V)
• Rectified output: roughly 12 V DC per half after a rectifier and smoothing capacitor, higher with no load
• Operation: AC only; a transformer does not work from a DC source

Transformer 9-0-9V 20VA Applications

• Regulated 5 V, 9 V or adjustable supplies with 7805, 7809 or LM317 regulators
• Split (±) supplies for op-amp, mixer and preamplifier circuits
• Powering relay, timer and control boards
• Replacement transformer for electronics repairs
• Student projects on AC to DC conversion

What's in the Box

• 1 × 9-0-9 V 20 VA transformer

Tip: Confirm that the primary voltage printed on the label matches your mains (220–230 V in Lebanon), add a fuse on the primary side and cover all mains terminals. Use a smoothing capacitor rated at least 25 V after the rectifier, as the peak DC voltage is about 12.7 V before diode losses.

Orders placed before 14:00 are ready for pickup the same day. Delivery across Lebanon usually takes 1–3 working days.