Trembo Tremolo - Pending Verification

Trembo Tremolo - Pending Tremolo.
JMP = JUMPER WIRE
VTL5C1 = optical isolator.
Control is KNOB and RATE.
Trimmer is to adjust the OPTICAL LED intensity.
LED beside trimmer is on-off indicator, connected to LFO to blink according to the LFO rate.
Familiar eh....pm me to know which TREMOLO this is modelled after.

Transformer-less DI Box - Pending Verification

Transformer-less DI-BOX
This box operate with 18v but i think can work with less voltage.
I create this to use with YAHAMA EMX5000 PA system to try a simple recording.
XLR is the balance output to be connect with XLR socket.
The square pad is the first pin, middle being the pin 2 and the last round pad is the pin 3.
SPK/LINE is the selector to switch LINE output or SPEAKER output.
Can be modded to operate in PHANTOM power mode.

Env Filter - Pending Verification

Plush Envelope Filter
All Diodes are 1n914 or equivalent.
All film caps have 5mm pitch.
OP AMP type is not critical. Any dual OP-AMP will work great.
SPDT is to change the sweep UP or DN; UP has very little effects.