You asked for a deep dive - You got a deep dive! I go all-in to find out as much as I can about the Conn ST-11 Strobotuner, with a full demonstration and break down of how it works with schematics and a teardown and more! Enjoy!
0:00 - Just Read The Instructions
4:27 - The history of the Strobotuner
5:30 - How the Analog Strobotuners worked
7:40 - How to calibrate the ST-11
9:40 - How to use the ST-11 to tune a guitar
12:39 - Opening it up!
14:40 - How it works!
26:10 - Scope Trace Time!
29:00 - No 60hz line frequency? No problem!
31:14 - Description of the internal boards and components
34:00 - Clean the contacts before closing it up
39:20 - Another try at calibration after cleaning
41:23 - Thanks To The Patrons!
Join Team FranLab!!!! Become a patron and help support my YouTube Channel on Patreon: http://www.patreon.com/frantone
#franlab #guitar #Strobotuner
- Music by Fran Blanche -
Fran on Twitter - https://twitter.com/contourcorsets
Fran's Science Blog - http://www.frantone.com/designwritings/design_writings.html
FranArt Website - http://www.contourcorsets.com
0:00 - Just Read The Instructions
4:27 - The history of the Strobotuner
5:30 - How the Analog Strobotuners worked
7:40 - How to calibrate the ST-11
9:40 - How to use the ST-11 to tune a guitar
12:39 - Opening it up!
14:40 - How it works!
26:10 - Scope Trace Time!
29:00 - No 60hz line frequency? No problem!
31:14 - Description of the internal boards and components
34:00 - Clean the contacts before closing it up
39:20 - Another try at calibration after cleaning
41:23 - Thanks To The Patrons!
Join Team FranLab!!!! Become a patron and help support my YouTube Channel on Patreon: http://www.patreon.com/frantone
#franlab #guitar #Strobotuner
- Music by Fran Blanche -
Fran on Twitter - https://twitter.com/contourcorsets
Fran's Science Blog - http://www.frantone.com/designwritings/design_writings.html
FranArt Website - http://www.contourcorsets.com
Hey Fran, great video! Our band used one of those in the late '70's. Only time I had trouble with it is when I found our drummer's stash in the little compartment. I wasn't happy about that.
Stew Mac sells a little guitar volume pot attachment to spray DeOxit in through the knob side so I assume it would work for sealed pots like the one that was giving you trouble.
Nice !
That was really interesting, it’s as old as me 🥹 Thank you Fran 💞
David Gilmour wont leave home without one!
Interestingly, like others here my exposure to this was in Junior High music department in the '70's. I was fascinated by this device. Little did I know at the time how much digital electronics would factor into my path.
huh..it was in tune when I bought it…
Great episode, Fran! I love the history and details you provide.
Thank you and your welcome. Thought you would enjoy making a video about this device. Since it hits a cross roads of your interests. I believe Peter Frampton had eight of these on stage in concert as a visual effect. Great video. Thank you.
It's somewhat hacky, but when access is difficult you can clip out old axial electrolytics flush with the case and solder to the stubs. Just have to solder fast, use RA flux. In fact I'd recommend doing it that way for some of the cheaper stuff with traces that disappear on the third or fourth reflow.
Great video. Thank you for taking the time to do it.
Love this kind of stuff
Glorious. Teach, Fran!
I like that they used a tin can as shielding for the motor. I think they used a wire wound pot because they last longer then carbon track pots.
I have the old ST6 unit…motor won't run. Also, you can spray the cleaner between the shaft and bushing….with shaft up, it'll gravitate to the wiper. Great video, thanks!.
I designed a divide by N countdown freq gen in the early 1970's using 7474's that uses several switches to "pre-stuff" numbers into the counter chain (1,2,4,8,16,32,64,128,256,512,1024.. can't recall if it went up even courser, lol). Using a punch card generation 12th root of 2 printout calculation, the exact output freq and octave was easy to set. It makes a sloppy square wave output that then relies on the human ear for pitch comparison. Dual D versus the JK you clearly described. I still remember, "Not Q follows Data" THANK YOU FOR THE REVIEW.
I then bought a Peterson strobe tuner about 40 years ago. It's' only a generation or so newer than your ST-11. My Peterson features strobed red LED's instead of the Neon lamps. I still use it about twice a year to tune and stretch my piano; the spinning disc sync motor bearings rattle a bit at various "speeds" but that clears up with a little overall tilting, lol. Such interesting history… For equal temperament, the secret is the 4ths need to stretch and 5th need to compress just a nudge…
This is a difficult watch but very interesting from a technical point of view! I was in a signed band supporting Martha and the Muffins at the Nashville rooms in London in the late 70's. There was one of these in the dressing room and like the young idiots we were we had no idea how to use it but thought it was a good idea to try. We went on stage totally out of tune and were sacked by our label the same night! To this day I've no idea why we didn't just use our ears!