Potentiometers have been used for over 70 years for applications where varying a resistance is necessary as part of an electronic circuit. Typically carbon based tracks were employed for many years but when power ratings of several watts are required then the use of a wire wound element is preferable as greater power dissipation is possible.
A local high specification audio amplifier manufacturer needed a high reliability wire wound potentiometer to act as a volume control in one of their amplifier designs. The potentiometer required a 2.2 watt rating and the AW potentiometer was deemed to be a suitable candidate as it met the following requirements for the applications:
- 500 volt d.c. across end terminal rating. The circuitry in the amplifier employ vacuum tubes ( a common trend in ‘high end’ audio amplifier design is the usage of vacuum tubes (or valves as they are also referred to)). Therefore a high voltage rating for the potentiometer was important
- Dual gang
- Reliable wiper arm operation. The wiper arm on the AW Potentiometer has 2 contacts ensuring high reliability. This is very important in audio applications where unreliable contact between the winding and wiper arm can generate ‘noise’.
- Compact size. The 24mm body diameter was suitable for chasis mounting.
- Local supplier. The benefits of having locally manufactured electronic components cannot be underestimated for both low and high volume, local manufacturers. This wire wound potentiometer is available on a 2 to 3 week lead time, with custom resistance and single or twin gang options both being readily available.
AW Series Wire Wound Potentiometer