AUDIO FILTERS & AUDIO PROCESSORS 

2/2/2016

Publication

Reference Article

Board Price

N0SS AUDIO FIX FOR K2 cLICK HERE FOR: (NOTES ON k2 FIX) AND (FOR BOARD LAYOUT).

$4.00

W2MY/5 Audio Break Out Box

$7.00

AA-10A-1 25 Watt Audio Amplifier by John Keith details at http://www.bwcelectronics.com/projects/AA10A090.pdf

$16.00

The SM0VPO 4 watt audio amplifier .See details on FAR DVD

5.00

Motorola replacement 5W audio board for older style expernal speaker

$8.00

ARRL HB CHP28 FIG.10 (92)

Audio amp with AGC (also CHP28 FIG.15 (88-91))

$4.50

ARRL HB CHP28 FIG.13 (92)

An expanded headphone mixer (also CHP28 FIG.18 (88-91))

$4.50

ARRL W1FB QRP NTBK 1991 FIG. 3-22

Active CW filter

$6.00

73's May97

Audio multiplexer for your frequency counter for measuring CTCSS tones by KB8XI

$6.50

73's Nov96

Magical audio filter using MC1458 &MAX295 IC1s BY Jim Pepper

$7.00

73's May94

Cripe hyper audio filter

$5.50

73's Dec93

Deluxe COMM audio by Curry

$8.50

73's Jul93

Universal speech processor

$5.25

73's Feb93

Switched capacitor audio filter tone processor

$5.00

73's Nov92

The noise remover, basic noise limiter

$3.50

73's Nov92

The noise remover, basic noise limiter, plus filter

$4.25

73's Nov92

The noise remover, basic noise limiter, plus filter & amp

$4.50

73's Oct92

Noise blanker (larger BD)

$4.50

73's Oct92

Noise blanker (smaller BD)

$3.50

73's Aug92

Digital alc

$9.00

73's Jun91

HW-8 audio amp

$3.50

73's Jun91

Pseudo CW filter

$6.00

73's Dec90

Audio power tape recorder controller

$4.50

73's Sep90

Solution AGC circuit

$5.50

73's Apr90

Blanker for TS940S

$4.50

73's Feb90

Contest quality headset and MIC amplifier

$4.50

73's Dec89

VOX for THs

$3.00

73's Jul89

4 IN/5 out audio mixer

$9.50

COMM QRTRLY Winter 97

Logarithmic audio speech processor by W. Sabin (two board set)

$14.50

CQ Jul97

WIFB QRN 'squelcher' MK-III project

$5.50

CQ Nov96

Desk top microphone preamp using 2N7000 FET by Rich Littlefield

$3.50

CQ May96

WIFB 'squelcher' noise eliminator MK-II

$5.75

HR Apr89

Multiband speech processor

$4.50

NUTS&VOLTS OCT'07

Analog mixed and matched, a 4input/output distribution amp by Cicchinelli, 4 board set

$18.00

NUTS&VOLTS Mar03

National semiconductor LM4752 board

$11.00

NUTS&VOLTS Dec97

MIDI to synthesizer interface by Thomas Henry (source code available from http://www.prairie.lakes.com/~map/ )

$13.50

NUTS&VOLTS Jul93

Parabolic microphone amplifier by Charlton

$4.50

PE May98

Portable CD dual 4 watt amp by Davidson

$8.50

PE Dec71

Distortionless audio compressor ( click here article)

$7.00

PE Sept' 74

Build a 400 watt stereo audio amp the Ampzilla 2 board set

$33.00

QEX JAN/FEB 08

A squelch amplfier by KE5KSC

$7.50

QEX Sep/Oct01 (Tech Notes)

Digital audio amplifier by Ulbing

$5.50

QEX Jul85

Morse code shaper

$12.50

QRPp Summer98

Switch capacitance audio filter by Jim Pepper

$6.00

QST Feb 17

An ocvillator for MCW by wb9ybm (CKICK HERE)

$4.00

QST APR 16

CW TONE DETECTOR. With NE567

$6.00

QST APR16

CW Tone Detector Boards (click here)

$4.50

QST Aug15

headphone amplifier

$7.00

QST Jun08

Audio interface for field/contesting by K0IZ (SEE PICTURE)

$8.50

QST JAN07

Simple computer to transmitter morse keyer interface click here

$4.00

QST JUN06

Low cost active audio filter for CW using LM324 by WA9PYH

$5.00

QST Jan05

An audio intelligibility enhancer by N4GG

$8.50

QST Dec02

EQ5+ microphone equalizer by ND2N, 2 board set

$13.50

QST Jul02

Improve audio equalizer by WB9YBM

$5.50

QST Feb02

CW generator and audio distribution system by Rynone

$8.00

QST Dec00

Noise canceling with electret condenser microphones by Spices

$4.50

QST Nov99

PTTSound BY EB3NC

$7.50

QST May00

Improving the hamtronics R139 VHF weather- satellite receiver interface by Jim KOCSIS

$4.50

QST Jul98

A voice balancing audio peak clipper by John Burger

$6.00

QST Nov97

Six channel distribution amp by Sumner Weisman

$7.00

QST Nov95

AMSAFID, an automatic microphone switcher amplifier filter integrator distributor by Mandelkern

$7.00

QST Jun95

Continuously variable bandwidth audio filter using MAX295 IC'S by Bramwell

$7.00

QST Mar95

Audio break-out box by Spencer

$7.00

QST Feb95

AGC audio preamp by Miller

$4.50

QST Dec94

Spencer 1 W AF amplifier

$4.50

QST NOV 94

Two tone generator using two transistorts socillatoes.

$5.50

QST NOV 92

Dual audio speakers by

$4.50

QST Dec91

Quality desk mike

$4.00

QST Aug89

Desk mike audio booster preamp by Demaw (also ARRL HB'96 page 22.29)

$4.50

QST Oct83

A tunable CW filter

$6.00

R.CROWLEY

COMCLONE 2 by Crowley

$9.00

ANALOG DEVICES SSM2165

SSM2165 speech compressor mini-kit, (2) OP113, SSM2165, 78L05, L1, and P C board

$26.50