• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

AM transmitter thoughts

Status
Not open for further replies.

SlicRic

New Member
Hi,
I am going to build a small low power AM (broadcast band) transmitter, I was thinking if I vary the number of turns on the coil can I get it to transmit at different frequencies, or will their have to be more involved modifications?
Thanks Mick
 

stevez

Active Member
You can vary the "C" with a variable capacitor. The "C" can be a single variable - or a fixed capacitor and smaller variable in parallel. Sometimes there will be a larger variable as sort of a coarse tune and a smaller variable in parallel as a fine tune.

The "L" can be varied any number of ways. Physically deforming the coil will change it somewhat. Coils with multiple taps work. You might also use a coil with a slug or core that can be moved in or out - slug tuned is one way of describing it.

Keep in mind that you are responsible for whatever signals you emit. In many countries low power broadcasting (within the rules) is allowed but only within the broadcast band. If you tune and operate your transmitter out of band you've violated the rules - even if you aren't aware of it.
 

Dean Huster

Well-Known Member
My only AM BCB transmitter I've made was the "Wireless Rebroadcaster" from Popular Electronics back around 1967 or so, using a single 12AT7 dual triode. Interesting that I've never considered building a solid-state model.

Dean
 

bigkim100

Banned
Dean...why does it say RIP in your profile?...mkes you sound like you are dead....but if yoou are posting you must be undead
SSSSSSSSSSSSSSSSSSSSCCCCCCCCCCCCCCCCCCCCCRRRRRRRRRRRRRRRREEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAAMMMMMMMMMMMMMMM!!!!!!!!!!!!
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top