Hello Theremin World,
Here's some background info on me (skip past to get to my question):
My name is Kevin. I am a Library Services Associate for the Carnegie Library of Pittsburgh. I work in the Music Department of the Main Branch, where I help manage the Musical Instrument Lending Library.
Some background information on this collection:
Founded in 2017
Enjoyed by patrons of all ages
Around 70 items currently in circulation
Permanent display table at our Main Branch features larger, more expensive items, including:
Moog Etherwave Plus Theremin
Pittsburgh Modular Lifeforms Foundation Evo
Custom Serge Modular Synthesizer
Moog Model D
So far in this role I have had to make minor repairs to some equipment: re-soldering loose connections, applying DeoxIT spray, updating firmwares, etc. Our Etherwave Plus was damaged recently when a patron knocked the pitch antenna loose, disconnecting the antenna wire and damaging that joint of the box. I re-soldered that wire and re-glued that side of the box. I then attempted to adjust the tunable inductors of L11 and L6 (I did not touch L5). I did this with a metal hex screw driver, and immediately damaged both cores. I realize how foolish this was. I was simply too impatient to order a proper tuning tool (ours was nowhere to be found when I started and I was reluctant to spend my own money to order another :getlost
.
I spent a few hours yesterday researching the Coilcraft SLOT TEN 5-10 inductors I damaged, including reading through dozens of posts on this site. I apologize to the regulars of this forum for contributing yet another post on this topic. Unsurprising to you all, the 5-10s appear to be all gone. I reached out to Coilcraft to see if they had anymore and they replied soon after that they have none left. I was unable to find them listed anywhere else online. I did find a listing for some 5-11s. I am wondering if it is possible to swap the ferrite cores from those for the damaged cores in the 5-10s in our Etherwave. I have read about radio enthusiasts doing this for RF inductors but could not find an example of this repair for the variable inductors in theremins.
For now I have replaced our Etherwave Plus with one of our Moog Theremini's that are available for checkout. It's a fine substitute, perhaps more kid friendly with the digital fx, but it doesn't have the presence of an Etherwave. Also it takes one item out of circulation. We have a Big Briar Etherwave in our offices as well. I thought about substituting this but it does not have a headphone out. Also there is no power indication light, which one of our patrons who has a pacemaker looks out for when entering that part of the building.
Anyway, thank you for reading. I promise I tried to do my research before posting. I am truly grateful for this forum as a resource. Any response is greatly appreciated. Our Etherwave is the most popular instrument we have here at the library. Dozens of patrons use it every week. I'll do whatever I reasonably can to fix it.
Best,
Kevin