insttech's Profile

Marantz 1090 protection cct PUBLIC

Sometimes the simplest thing can cause a lot of grief. Marantz 1090 stereo console amplifier protection circuit failure had distorted the audio from the pre-amp to the main amp. All fixed now.

by insttech | updated October 28, 2025

distorted-audio   marantz-1090  

Hand Valve Limit position switches PUBLIC

by insttech | updated April 12, 2025

Philips SP-25 crossover PUBLIC

Philips SP-25, 2 way passive crossover.

by insttech | updated August 16, 2024

Celestion SL6 Xover PCB PUBLIC

by insttech | updated August 08, 2024

Stereo VU meter PUBLIC

by insttech | updated January 25, 2024

DOD 1222XL power supply PCB PUBLIC

A simple schematic for your DOD 1222XL mixer.

by insttech | updated January 25, 2024

Christmas Wreath lighting controls PUBLIC

by insttech | updated January 25, 2024

Power/ Flasher module for indoor LED lights PUBLIC

by insttech | updated January 25, 2024

Pulse153 crossover PCB PUBLIC

by insttech | updated January 25, 2024

Wall-plug adjustable DC motor control signal PUBLIC

by insttech | updated April 20, 2016