DIY modules #5 - matrix mixer?

Seems likely a matrix mixer as there is alot of repetition of components, most of which are op amps and 100k resistors. The PCB looks half finished.

DIY modules #4 - dunno

Lots of poly caps, transistors, blinkenlights and op amps

DIY modules #3 - fixed bandpass filters

This module weighs a couple of kg, due to the stacks of inductors bolted inside. It's function was obvious enough but the faint writing on its side confirms.

More like to read 'fixed filter bank'

DIY modules #2 - clock

This one has a MM5316N chip, which is a digital alarm clock. It uses numitrons for the display, these look like nixies but run at 5V or less. Obviously the push buttons are to set the time & alarm, hopefully the outputs give second count (60BPM?).

DIY modules #1 - reverb

Some of these have 'JAN electro...' 'Meguro' stickers on the panels but are otherwise unlabelled. I will make a page for each one and update them as necessary.
This one is hooked up to a reverb tank, so no mystery here, other than does it work and whether it is VC-able.

getting packed and shipped from Japan

This synth has lived in Japan for the past 40+ years, but is now here in Aus.

It needs a service - revive dead modules (not too many), recap the PSUs & change the transformers to suit 240VAC. The keyboards need some TLC as well.
The cabinet on top is full of DIY modules nothing is labelled and some of them are just the panel with no PCB behind. These will be either identified or replaced with nonlinearcircuits modules, to be chosen by the owner of this ridiculous hunk of wood, metal, plastic & various minerals.

Crikey!