Brian Roth
Well-known member
Rather than pollute this thread:
https://groupdiy.com/threads/mxr-auto-phaser-schematic.82403/
...I decided to post some 50+ year old memories.
1969/1970 era I was a sophomore in High Screwel <g> and met a guy named Alan Miller. He had worked with the Hammond Organ dealer in Lawton, Oklahoma and designed a line of products for the music biz.
The Leslie simulator was trademarked as "Spin" and used six photoresistors circled around a central incandescent lamp. The lamp's "blinking" would speed up and slow down to adjustable rates to emulate the Leslie's speed changes.
Each photoresistor was part of a six stage phase shift circuit. That was summed with the input signal to create a semi decent Leslie emulation.
Based from Miller's circuit, I built one on "cracker board" and installed it into a friend's M100 Hammond which had been cut down to a portable (remember the Hammond "Porta B"?...this pre-dated that organ) by our local Hammond organ guru. My friend Bruce gigged with that for years.
Somewhere I should have schemos/notes.
Just TMI and memory rewind!
https://groupdiy.com/threads/mxr-auto-phaser-schematic.82403/
...I decided to post some 50+ year old memories.
1969/1970 era I was a sophomore in High Screwel <g> and met a guy named Alan Miller. He had worked with the Hammond Organ dealer in Lawton, Oklahoma and designed a line of products for the music biz.
The Leslie simulator was trademarked as "Spin" and used six photoresistors circled around a central incandescent lamp. The lamp's "blinking" would speed up and slow down to adjustable rates to emulate the Leslie's speed changes.
Each photoresistor was part of a six stage phase shift circuit. That was summed with the input signal to create a semi decent Leslie emulation.
Based from Miller's circuit, I built one on "cracker board" and installed it into a friend's M100 Hammond which had been cut down to a portable (remember the Hammond "Porta B"?...this pre-dated that organ) by our local Hammond organ guru. My friend Bruce gigged with that for years.
Somewhere I should have schemos/notes.
Just TMI and memory rewind!
