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Headphone Amplifier

Headphone Amplifier... [read more]

Power Amplifier 8W

Although the TDA2030 can deliver 20 watts of output power, I deliberately reduced the output power to about 8 watts to supply 10 watt speakers. Input sensitivity is 200mV. Higher input levels naturally will give greater output, but no distortion should be heard.... [read more]

Repeating Timer No3

This circuit is very similar to Repeating Interval Timer No.2 . However - the addition of a light dependent resistor means that the operation of this timer can be limited to the daylight hours. A variable resistor (preset) lets you choose the level of darkness at which the timer will cease to function.... [read more]

Bench Amplifier

A small 325mW amplifier with a voltage gain of 200 that can be used as a bench amplifier, signal tracer or used to amplify the output from personal radios, etc.... [read more]

Amplified Ear

This circuit, connected to 32 Ohm impedance mini-earphones, can detect very remote sounds. Useful for theatre, cinema and lecture goers: every word will be clearly heard. You can also listen to your television set at a very low volume, avoiding to bother relatives and neighbors. Even if you have a faultless hearing, you may discover unexpected sounds using this device: a remote bird twittering will seem very close to you.... [read more]

Modular Preamplifier Switching Center

This module can be a necessary addition to the Modular Preamplifier Control Center when more than two sources need to be connected to the preamplifier chain. Four high level inputs can be selected by means of SW1 and routed to the output. The output of this module must be connected by a suitable cable to one of the two inputs of the Control Center module. In this way, a total of five inputs will be available to the user of this module combination.... [read more]