What does it take to build a D-Lev today ?

Hey folks.

I'm really enjoying working on my ArtDeco Open Theremin. I am almost done and I'm looking for the next project. (Don't worry, I'm playing long term and I still have to practice) I have some technical issues to solve with it, though. Nevertheless, I'm still on the quest to find the ultimate theremin. 
The etherwave pro is far too rare and too expensive for my case. I've lurked on the Claravox when it came out but couldn't afford it (turns out that it's for the best anyway). The subscopes seem very much appealing, probably a bit expensive too. 

The D-Lev however seems to tick all the boxes. 
I'm not in the analog-digital fight, I've been there a long time and I'm happily using soft synth for my music production, as well as some analog gear. Which of which is better is a wrong question imho.

Since there is no kit for sale, I thought I may buid one from scratch.
From a theoritical point of view, I imagine that the steps would be :
• Get the gerber files and have the PCBs made thanks to an online service
• Order the components online thanks to the BOM
• Populate and solder the boards
• Upload the code to the processor
• Make an enclosure

None of these steps scare me, I've done a lot of DIY projects and some Arduino dev.
But I have no knowledge in engineering and electronics, which means that I'll probably stumble on something at a point and I'm not really fit to troubleshoot by myself. So I'm guessing that it involves much more that the "simple" steps above.

My question would be : How far am I from the truth ?
Thanks for your insights !

"My question would be : How far am I from the truth ?"  - Francesco

I don't want to discourage you, but I guess I don't want to exactly encourage you either!   A few others with more EE experience have taken a crack at implementing it, and they have run into a bit of trouble here and there.  Nothing earth shattering, but I tend to forget how much intuition one develops over a decade+ of doing Theremin design work.  Even though the circuitry external to the FPGA board is fairly simple, I wouldn't recommend it as a first real electronics project.  Having said that, using the kit PCBs (as you are considering) is what I would recommend as a starting point.  Do any custom implementation after that's up and running and you develop some experience with it.  I could certainly help you with any issues you might run into.  You will need a decent oscilloscope.

The kit has been on hiatus for over a year now due to some health issues, though they are hopefully largely past now.  I'm reluctant to make more kits in their current form because incremental improvements could be made.  I want to:

1. Increase the inductance of the coils, perhaps 4x.
2. Improve the AFE if possible.
3. integrate the coil, AFE, and plate antenna as a unit.
4. Switch to CAT5 interconnect for the AFEs.
5. Use 5V LCDs if possible.
6. Use PCB material for the control and tuner panels, as well as the logo plate.
7. Beef up the ESD protection.
8. Mount the dedicated mute LED on the control panel.
9. Rearrange the expansion port, separate it into two.
10. Possibly reduce the encoder interconnect and handle them more in SW.

Right now I'm working on #1 thru #3, but it's slow going.

If you want to have a video discussion PM or email me, I'd be interested in meeting you.

Hey dewster,
Many thanks for your reply. This is the kind of answer I was expecting for. Like, "sure go ahead but you'll run into problems" 
Even if I'm no EE, it's not my first electronic project, I'm part of a droid building community and i spent a lot of time messing with electronic parts. That's why I said I wasn't afraid. But I know it could be a long journey.
I really appreciate you're willing to offer some help. Thank you for that!

I'm in no rush, and some of the improvements you're mentionning seem to be worth waiting (escpecially the 5v LCD!). But i know I can run into some form of hurry and start the dive no matter what.
After long thought of course.

It would be a pleasure to meet you. I'm just enjoying my weekend before two busy weeks, but if you're ok we can meet after that.

PS Really glad you've recovered I was worried reading you had issues.
Cheers

Hi Francesco,

I built my own D-Lev from scratch with a lot of help from Klaus Hoffmann, alias Gerbold on this forum.
Klaus made some changes on the encoder boards and designed a specific I/O board to minimize interconnections.
For everything else, he used the original D-Lev design.

He sourced a total of six sets of PC boards and components, one for himself, three for his friends and two for me.

You can read his messages on this forum, starting from here.

I'm an experienced hoobyist in electronics. I have designed and assembled several microprocessor based radio-control transmitters and receivers.
However, i must say that would probably not have succeded with my D-Lev without Klaus's help, and also dewster's.
Thanks to both of you.

If you decide to build yours I'll be glad to help you. 

I'm going to build a second D-Lev, just because I'm not satisfied with my enclosure, which was initially supposed to be a mockup. (It's made of MDF)
You can see it on this page.
I want to make a more precious wood enclosure. Rather than transferring the electronics to the new enclosure, I will make a new set of electronics and keep the firts D-Lev as is. Which means that it could be for sale in the future, but I can't say exactly when.

If you want to contact me, I send you a PM.

Great, André, thanks for the words.
Sure, I'll keep in touch. Will be great to talk about all this !
See you soon then!
f.

OMG, i am very glad to read this, certanly i am one of you all, with a some expertise in analog and digital electronics with a lot of desire to have a D-Lev, i would very happy to get into this Electronic Odyssey. Please let make a group to create this Theremin. I am from Chile

Sure, we could follow up this topic or create a new one ("Let's build the (mostly) digital theremin" ) and have a group of builders with help from each other.
This may be one of the last build batch before Dewster's new version.

I won't promise to be full time or even consistant, I know that some times of the year can be very busy and make me stray off some the goals I set to myself. This is the perfect candidate for a quick-starting-fast-progessing-then-set-aside-for-month-then-going-back-to-it-with-fear-and-frustation project, haha

Still, if a few people are interested it could be worthwhile.
Starting with the fact that ordring PCBs are usually in batches. So, I could order a set (i think minimum is 5) and we share the costs. I'm in France, so it may not be the best option for you, robonil :/

This way, we could check together if the pcb set is the right one, or maybe share the basket from a component supplier...
What do you think ?

I would love to build a D-Lev as well, but I have a couple concerns.

1. I could afford it, but it is hard for me to justify spending money, no matter the cost
2. My electronic experience is… almost non existent, and the D-Lev does not seem like a beginner project 

Regardless, building a d-lev sounds great, and I might even jump in if we do make the build group a thing, but I doubt I am ready.