EHX - Deluxe Electric Mistress - Version 1 - EH 1318A

A very early Electrix Mistress, deluxe.
I think this dates from 1978.

This uses the SAD 1024 Bucket Brigade chip.
The marking in pencil is a reference to a later version ? Version 2 or 3 used the EH 5150 PCB.

The EHX Delux mistress is a early flanger.

Flangers have been around for ages .. since the 1940/50s.
Les Paul in 1945 ??
They originally used two tape recorders ... one running slightly out of sync / slower than the other.
From what I've read, the first flanger using an bucket brigade delay ICs was the Eventide instant flanger FL201 in 1976 This beauty had CV controls that allowed modulation of the effects using modular synths.
The  Eventide used two Panasonic MN3001s clocked at 2.7 MHz.

Eventide today make a software version of this classic rack effects unit.


The PCB is labelled EH1318 A which makes it a Version 1 from 1978.
Notice the curled knob with pointer.
The IC's are: 1x LM78L, 1x 4558, 1x SAD1024A, 1x LM324, 1x LM311N, 1x 4013BE
with one transistor ... a 2N5087.





Links:
 + Metzgerralf - V1 pics
 + How the Flanger works - detailed
 + Reverb - Eventide FL201