Electronic – can I use a choke 150uH inductor for the AM transmitter circuit

amcoiltransmitter

I am trying to develop an AM transmitter but I am having problems with getting a variable capacitor and inductor (for the rf circuit) in my location. I was able to find a choke coil with an inductance of 150uH but most of the circuits I was able to find in the net have 200uH inductors. Is it possible to use this inductor?

edit:

Here is the link to where I am going to base my circuit on:
http://www.zen22142.zen.co.uk/Circuits/rf/amtx.htm

and here is the link to the inductor I am planning to use:
http://www.e-gizmo.net/oc/index.php?route=product/product&product_id=45861&search=150uH

for the capacitor of the rf amplifier, only 75pF trimmer capacitors are available in our nearby shop
so can I use constant capacitors in parallel so I could still control the capacitance?
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Best Answer

Yes, you can use 150 uH inductors if you adjust the values of the parallel capacitors to keep the resonant frequency where you want it.

Yes, you can add fixed capacitors in parallel with your variable capacitors to "center up" the adjustment range around your desired output frequency. Of course, the adjustment range will be much smaller (more narrow). You can use the calculator on the website you linked to determine how much external capacitance to add. The calculator uses total capacitance, so you should subtract 1/2 the max value of the variable capacitor to see how much external capacitance to add. This will optimize the adjustment range.

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