Hi.
Say a monolithic oscillator, integrator to make it sinewave, and final amplifier transistor/IC...
Aiming for VLF 100KHz RF TX, voice modulated, less than 100mW.

What dedicated or convenient integrated circuits in the market could be used ?

 

Hello,

Maybe this book will give you some ideas:
https://archive.org/details/fea_RSGB_Low_Frequency_Experimenters_Handbook

Bertus

 

 

Your biggest problem transmitting on that frequency is the antenna as the wavelength is 3000 metres. Also you will probably not be able to obtain a licence to transmit on that frequency.


Les.

 

Thanks, Joey. That is in the line of plans.

Thanks Les. The antenna may end being smaller than a stamp, known as 'telecoil' * , as resonant wound ferrite rod. For the licence, I do not care a bit.

----> https://duckduckgo.com/?q=dfc77+antenna&t=canonical&iax=images&ia=images

* ---->

 

Your biggest problem transmitting on that frequency is the antenna as the wavelength is 3000 metres. Also you will probably not be able to obtain a licence to transmit on that frequency.


Les.

I'm not up on the current rules but isn't it legal under a certain output power and antenna limits. 100 mW runs in my mind but I'm sure that is wrong.

As for license, I would absolutely worry about it as the FCC is quite zealous about enforcing the rules and Ham radio guys are very much a part of that.

 

Thanks Les. The antenna may end being smaller than a stamp, known as 'telecoil' * , as resonant wound ferrite rod.

What makes you believe that that coil resonates at 100 kHz?

Even if it does, using a coil like that for receiving from a high-powered transmitter is very different than transmitting using such an antenna.

For the licence, I do not care a bit.

Are you saying that you don't care whether what you are trying to do is legal or not?

 

Thanks, gentlemen.
To be exact, will be at 136 KHz, and I do have two licenses, so I do not care. That type of coil with a proper capacitor for resonance should work for a few metres. But a 10cm rod is in plans. Just showing a sub-stamp sized rod.

 

Will the lawyer in this Thread please offer a reference for the FCC regulation concerning a 136 KHz transmitter with an effective range of 10 feet +/- 50%
And then tell me how the FCC gets their scofflaw truck within 10 feet of the offending transmitter.