RCA BA-1A two-stage preamp schematic - Schematic
RCA BA-21A preamplifier schematic - Schematic
RCA BA-31A preamplifier schematic - Schematic
RF Preamplifier - Input needs only several mWatts (e. g. BF900) -> 300 mWatts OUT. This schematic is a often used buffer. It's easy to build, clean and cheap. When you want even more power, you can replace the 2N2219a by a 2N4427 or 2N3553. You can lower the output by adding a little resistor (10.47 Ohm 1/2W) in the emitter line of the 2N2219a.
Simple Antenna Preamplifier for AM Radios - AM radios are still used for capturing transmissions from long distances (DX reception). But AM radios normally require long (10-30m) outdoor antennae. That is easy if you live in a village __ Electronics Projects for You
Simple Circuit Audio preamplifier - This is a very easy circuit to buildall parts can be found at the local electronics shopno matter how worthless it (the local shop,) usually is. __ Designed by Andy Wilson
Simple Circuit Balanced Mic Preamp - This is a "utilitarian" preamp. Although not intended where lowest noise is needed, it is still quiet enough for most applications, and will almost certainly be all that's needed for adding a microphone input to an amplifier or powered speaker __ Designed by Rod Elliott ESP
Simple Circuit High Quality Hi-Fi Preamp - As it says, simple, high quality preamp. Has all the facilities normally expected __ Designed by Rod Elliott ESP
Simple Circuit microphone preAmplifier #3 - This is a simple microphone preamplifier circuit which you can use between your microphone and stereo amplifier. This circuit amplifier microphone suitable for use with normal home stereo amplifier line/CD/aux/tape inputs. This microphone preamplifier can take both dynamic and electret microphone __ Designed by Tomi Engdahl
Simple Circuit Pre-Amp with One Transistor - This is a very simple pre-amp circuit which use a transistor as a active component to boost the input signal. Its simplicity makes this circuit easy to built and inexpensive. The microphone used in this circuit is electret type which is very sensitive detecting the sound around its.
Simple Circuit Stereo Electret Microphone PreAmplifier - The leftmost 10k resistor supplies plug-in-power to the electret, forming part of the FET amplifier in the electret capsule. This could be anything from 2k to 10k, the higher the better the stereo separation (another mic derives bias from the same rail). Apparently higher values also lower distortion, and the best bias power circuits involve actually breaking a trace on the electret capsule to allow the use of both a drain & source resistor, but I’m not going that far.
Simple RF Preamp - I built this RF preamp from junkbox parts. The common-gate circuit provides an input return loss of > 18 dB from 88 to 108 MHz. The corresponding mismatch loss is < 0.07 dB. I could not find a recommended source impedance for lowest noise figure. I went for a good match instead since input mismatch loss directly degrades the noise figure. __ Designed by Brian Beezley K6STI
Simple Transistor Audio PreAmplifier - This easy circuit provides good gain to week audio signals. Use it in front of an RF oscillator to make an RF transmitter that is very sensitive to sound. __ Designed by Tony van Roon VA3AVR
Single IC Audio Preamplifier - Circuit only, no description is included. __ Designed by Tony van Roon VA3AVR
Sound Blaster Microphone PreAmplifier - Dynamic microphones can be connected to SoundBlaster if a suitable microphone preamplifier is built which can amplify the signal levels from dynamic microphones so much that they give enough level for SoundBlaster. This amplification can be quite easily done using simple single transistor microphone preamplifier circuit __ Designed by Tomi Engdahl
Stereo Electret Microphone PreAmplifier The leftmost 10k resistor supplies plug-in-power to the electret, forming part of the FET amplifier in the electret capsule. This could be anything from 2k to 10k, the higher the better the stereo separation (another mic derives bias from the same rail). Apparently higher values also lower distortion, and the best bias power circuits involve actually breaking a trace on the electret capsule to allow the use of both a drain & source resistor, but I’m not going that far.
Stereo Line Driver - A stereo line driver for feeding long cables or buffering an audio source. __ Designed by Andy Collison
Stereo PreAmplifier - Simple circuitry suitable for moving-magnet cartridges. Passive high-frequency equalization __ Contact: Flavio Dellepiane, fladello @ tin.it
Studio Series Stereo Preamplifier - Designed for the audio perfectionist, this superb preamplifier uses the latest high-performanceop amps for ultra-low noise and distortion __ SiliconChip
Studio Series Stereo Preamplifier - Installing The Modules In A Case __ SiliconChip
SW RF Pre-Amplifier - A radio frequency amplifier to boost SW reception. Frequency range approximately 5 to 20 MHz. __ Designed by Andy Collison |