TOKO Inductors Needed for EM Theremin!

The potentiometer won't help. You are building
beat frequency oscillators and the frequency
is set with an inductor and a capacitor.

Read through the circuit operation section of
the EM article and pay particular attention
to the tuning section.

(* jcl *)

Yes, it is clearer after reading the plans again with some more knowledge of what's going on.

Would I most likely end up with a reasonably functional theremin if I used the Toko substitute inductors and the Coilcraft substitute?

If so, I'd probably assemble it with the substitutes, use it, and if a better part came in, I could swap them.

Thanks

That sounds like a reasonable approach.

When you are doing your layout keep in mind that
the pin spacing on the TOKO and the Coilcraft
are slightly different.

Place Vector K24A pins around the periphery of
the inductor and use short buss-wire jumpers to
connect the inductor to the K24A pins. Connect
all other components to the K24A pins not the
inductor.

If you need to change the inductor you can unsolder the buss-wire jumpers without affecting
any of your circuitry.

(* jcl *)

You've mentioned Vector T42-1 pins and Vector K24A pins before. Will I need to be packets of 100 for these? Where else will I need to use these pins?

For power source, the modified Etherwave circuit says use 14 VAC, and the one I'm going by says 12-15 VAC. Should I use 12 or 14 VAC?

[i]You've mentioned Vector T42-1 pins and Vector K24A pins before. Will I need to be packets of 100 for these? Where else will I need to use these pins?[/i]

If this is the only electronics project you are going to do get 100 of each. Otherwise order 1000 of each. The tool for the T42-1 pins makes it much easier to insert them.

[i]For power source, the modified Etherwave circuit says use 14 VAC, and the one I'm going by says 12-15 VAC. Should I use 12 or 14 VAC?[/i]

Since this is a learning project your homework assignment is to read [b]AN-556: Application Note 556 Introduction to Power Supplies[/b]
which is at http://www.national.com/apnotes/Standard_NPN-Adjustable.html

;-)

(* jcl *)

Will I use pins for every connection and every component? How will I know which of the two pins to use?

The tool is 40$. If I just do this project, will it be reasonable not to use the tool?

Thanks

After reading the article, I think it doesn't matter if I use 12VAC or 15VAC- the regulators will give me 12 VDC either way!

If I use the Mouser #412-212053 12 VAC Power source, should the Mouser #163-4305 jack work for my power supply?

[i]
Will I use pins for every connection and every component? How will I know which of the two pins to use?
[/i]

I try to make all components connect to pins and then connect pins together with buss-wire. I use #22, #24 and #30 buss-wire. #22 buss wire fits through the side hole in the T42-1. #30 buss-wire will fit through the fine hole in the T42-1. The K24A gold pins are nice for connecting external wires too like the antenna, pots, jacks, and power supply connections

I will see if I have any example board that I can take a picture of. With free PCB software and low-cost vendors I usually don't breadboard
things anymore.

[i]
The tool is 40$. If I just do this project, will it be reasonable not to use the tool?
[/i]

$40 is an outrageous amount of money for that tool (Vector P149A). The tool consists of a wooden handle and a metal shaft that holds a T42-1 clip. I was thinking it would be in the $15-$20 range. Mouser has another tool for T42-1 pins which is the Vector P149 that costs $28. You should go to the Vector website and see what the difference is.

I wouldn't spend the $40 for one project but for $28 I would buy it.

(* jcl *)

[i]
After reading the article, I think it doesn't matter if I use 12VAC or 15VAC- the regulators will give me 12 VDC either way!
[/i]

There is one more thing to check for your power supply design --- power dissipation of the voltage regulator. The higher the voltage
into the regulator the more power you dissipate in the voltage regulator. The more power you dissipate the hotter the regulator runs. The maximum junction temperature of the regulator is probably around 150 degC.

There should be a disscussion about power dissipation in the article. The calculation of maximum junction temperature is not difficult.

(* jcl *)