Only Getting ~80Hz Range on Pitch Antenna - Circuit Issue or Room Issue?

Hi everyone! I'm coming around to actually making a build I've been planning for a month or two. I can see the change in frequency from the pitch antenna, but my range is only about 80 Hertz from zero-beat to very very close. How can I fix this? Or do I just need to play in a very empty room?

Far:

Near:

For context, this is my setup for testing:

For context, my linearizing coil is 40mH, if that helps. I'm following this tutorial: http://www.thereminworld.com/Article/14695/a-diy-wine-box-theremin (with some alterations for the volume antenna, which I could not replicate). Any advice is appreciated!

I'm now thinking the issue may also be the breadboards. Even though I'm only using rows with at least one row between them, I figure it may be causing some stray capacitances. Just want some confirmation before I solder everything onto protoboards. Has this happened to anyone else?

I'm now thinking the issue may also be the breadboards. Even though I'm only using rows with at least one row between them, I figure it may be causing some stray capacitances. Just want some confirmation before I solder everything onto protoboards. Has this happened to anyone else?

I assume you’re well on your way to getting a test theremin up and running.

Regarding your questions:
The room looks like a training lab; I’d be happy if that’s the case and if the students in your project learn more about the theremin.

If the tabletop isn’t metal but made of plastic or wood, everything should work fine. Also electric installations should not be near the antenas. Using a breadboard at this stage and at these frequencies is possible, and often even makes sense.

The problem is most likely the variable-pitch oscillator, and if I’m seeing this correctly, the 40 mH extension coil must have  - separated and before implementation measured - a significantly higher self frequency than the pitch oscillator. That also means that the Q-factor of this coil must be either high enough, or you need a series connection of several 10 mH coils with high Q-factors as shown in the diagram. 

Regarding the function: The function of the extension coil can be tested as follows: put a small capacitor of approximately 20-30 pF at the end of the coil and connect it to ground. Using a high-impedance probe on the oscilloscope (10:1), measure the resonant circuit voltage across this relative to ground. It should be in the range of several tens of volts peak-to-peak.
 
Without the participation auf the LC serial circuit, the range of the freuquency remains low.
Good luck for the next steps with your nice project!

scrapwiz, it might help if you could provide a closer view of your breadboards.

I would recommend that you place a layer of insulating plastic under the breadboards, having the underside so close to wood is likely inducing some stray C.

Check the resistance between the antenna and the transistor collector using a multimeter (i.e., verify the continuity of the coils and the wire-to-antenna contact). The reading should not exceed a few hundred ohms.

What type of coils are actually installed?

Hi everyone! Thanks for all the input. Sorry I always end up responding a few days late, but since this forum has been integral to me building this thing I figure I owe it a report afterward xD

JPascal: Indeed it is a circuits lab, but this is not a group project. I just wanted to build an analog theremin
Dewster: Good call on the insulation. I ended up soldering them on protoboards/stripboards (whatever the ones with the connected TH holes are called)
ILYA: Not sure on the resistances, the coils installed are Bourns RL181S-102J-RC

In summary, I have had a very long and arduous journey trying to replicate this build: http://www.thereminworld.com/Article/14695/a-diy-wine-box-theremin. The comments mention the LC filter after the volume antenna is incorrect (it is) but I also could not get the pitch oscillators to go above ~160kHz, which was giving me a horrible pitch field of like 300Hz. I found out the LC tank was resonating with the emitter capacitor as well (which I thought was just a bypass) and the feedback cap was way too high. These values give me a pretty good pitch field:

270pF capacitor for feedback
1nF capacitor for emitter to ground
~100pF capacitor for variable pitch, and about ~40pF + a variable cap for reference pitch

Maybe I'll make my own post after how much suffering this thing has caused me. Currently my biggest problems are bad soldering, the oscillators locking at low frequencies (I really need to add buffer stages between the oscillators and the mixer) and this low, raspy sound at low frequencies, which might be unregulated power supply? No idea.

Again, thank you all for your infinite patience. Some keywords in case anyone who needs this in the future can find it: Jason, 2013, wine box theremin, frequency too low, SRF

Bourns RL181S-102J-RC

Are you sure? The "102J" code denotes an inductance of 1 mH. But according to the schematic, 10 mH is required.