Vintage Peterson Model 400 Strobe AC Strobe Tuner with mic

Description

Vintage Peterson Model 400 Strobe AC Strobe Tuner with mic.  This was my father's tuner I used to get in trouble for sneaking to gigs when I was a teenager...god he'd get pissed!  He bought his Steinway B (also for sale) around 1974 and this came soon after.  As you can see it is in great working condition.
[I borrowed this description from a listing on reverb]
Peterson’s first strobe tuner, the Model 400, was introduced--variations of which would become the world standard for precision tuning for bands, orchestras, stage musicians, and musical instrument manufacturers.
It was the first solid-state strobe tuner, did not require calibration and allowed musicians to select one-cent increments. This was a major breakthrough for the strobe tuner and helped pave the way for Peterson to become the leading tuner company in the world.
Considered one of the most accurate tuning devices, strobe tuners, work in a different way to regular electronic tuners; they are basically stroboscopes. These can be used to tune any instrument, including the initial "beating" of steelpan drums, bagpipes, accordions, calliopes, bells, the pins in Music Boxes or any audio device much more accurately than regular LED, LCD or needle display tuners.
The strobe tuner was a common sight on stage and in the recording studio during the 1970's and beyond. Many will recall first seeing the mysterious flickering dials behind such luminaries as the Grateful Dead, The Who, Pink Floyd, Frank Zappa, Jimi Hendrix, Neil Young et al. Peterson tuners also took their place as a must-have in the road cases of their touring crews, which continues today!
This tuner is sought after by collectors and is pretty rare these days. It’d be a great addition to the bench of your repair shop or as a focal point in your musician’s man cave. It does not work as well as Peterson tuners do today but heck, it's about 50 years old.