Repairing a Moog Etherwave plus

Hello guys,

I have a Moog Etherwave plus theremin that I have upgraded with the ethermagic ESPE-01 module, however I managed to break the L6 coil whiel adjusting it and am looking to replace it. Problem is, it is a CoilCraft SLOT TEN-5-10 and I cannot seem to find it anywhere for sale. I was wondering if someone might have a clue where I could find some, or have some lying around that they are willing to spare (I am willing to pay), or if there is perhaps a suitable alternative.

Thanks in advance!

Did you damage the actual coil, or, what's far more likely, used some inappropriate tool and broke the ferrite slug? If the latter is the case, the best option is to find a replacement ferrite slug that fits the L6 coil (and the proper plastic tool to adjust it without breaking it).

I guess I broke the ferrite slug inside. I do have the plastic tool, I was a bit ignorant at first though and used a metal 
hex key. Is the ferrite slug a standard size? And do I guess correctly that I would have to desolder and take apart the inductor and thread a new one in?

I guess I broke the ferrite slug inside. I do have the plastic tool, I was a bit ignorant at first though and used a metal hex key. Is the ferrite slug a standard size? And do I guess correctly that I would have to desolder and take apart the inductor and thread a new one in?

Checked the datasheet, it appears to be a 5mm diameter ferrite slug, and I think it might just thread in from the top if I understand correctly, so I'll try to see if I can find some on aliexpress and replace it, thanks for the help!

Knowing what city, you are in might lead to better advice. I have a EWS board once used for experimenting you could remove the ferrite slug from.

If you try to un-solder the IF Transformer you will destroy the board, the copper traces are like tissue paper.

Use a magnet to lift out the ferrite pieces, give it a minute to then demagnetize.

An experiment is to tack on a 10pf (20pf) variable capacitor across the L43 coil that stands up.

Amazon
https://www.amazon.com/dp/B01N5KP1WG?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_3

Keep us informed.

Christophe S Becker
Old Temecula

Knowing what city, you are in might lead to better advice. I have a EWS board once used for experimenting you could remove the ferrite slug from. If you try to un-solder the IF Transformer you will destroy the board, the copper traces are like tissue paper. Use a magnet to lift out the ferrite pieces, give it a minute to then demagnetize.An experiment is to tack on a 10pf (20pf) variable capacitor across the L43 coil that stands up. Amazonhttps://www.amazon.com/dp/B01N5KP1WG?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_3Keep us informed.Christophe S BeckerOld Temecula

I'm from Brussels,  Belgium.

I'll try removing the ferrite core entirely today. So the experiment you are talking about, is the point to manually fine tune the theremin and leave the IF transformer Without a core?

You might also want to contact Thierry Frenkel (in France) and/or Wilco Botermans (in the Netherlands), they are the specialists in repairing and fine-tuning Moog theremins, both in countries neighboring Belgium. They might be able to help getting a coil or a ferrite core or offer further advice.

You might also want to contact Thierry Frenkel (in France) and/or Wilco Botermans (in the Netherlands), they are the specialists in repairing and fine-tuning Moog theremins, both in countries neighboring Belgium. They might be able to help getting a coil or a ferrite core or offer further advice.

Thanks a lot for the help, I have contacted both, and am waiting for a reply.

In the meantime I also contacted Moog Customer support, who told me they don't stock the part, and to find a suitable replacement on Amazon for a 42.3 µH variable inductor :/

Will keep you updated

No . . . leave the ferrite core in the coil to keep  the inductance value close to the original value.

The variable cap replaces the tuning characteristics of the broken piece of ferrite. In theory what I suggest could work but does not mean you will figure out how to get the oscillator back on its proper frequency. There are several tricks involved like over-coming the detuning by removing the wood box cover. 

Now that I know you are 9,000 kilometers away . . .Thierry is your best answer.

Christophe

No . . . leave the ferrite core in the coil to keep  the inductance value close to the original value. The variable cap replaces the tuning characteristics of the broken piece of ferrite. In theory what I suggest could work but does not mean you will figure out how to get the oscillator back on its proper frequency. There are several tricks involved like over-coming the detuning by removing the wood box cover.  Now that I know you are 9,000 kilometers away . . .Thierry is your best answer.Christophe

Ok, good to know, I will leave the ferrite in place then