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help about RF power supply

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contau

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I need a RF power supply circuit to reduce noise at 100Hz. I used 780x but it make noise so much. anyone can help me?
 
Your question does not make any sense.

What is an "RF power supply" ? I have never heared of such a thing.

How will an RF power supply reduce noise at 100hz?

Why is a 780x so noisy? Are you sure that it was decoupled properly?

JimB
 
i need a supply to transmit FM signal up to 1W.i used 780x but performence of FM is not good. received audio has the tone "ooooeeee " not like when using pin. i think that the reason for tone is the problem of supply.
 
There is no reason why a 780x should not work OK.

Ensure that it is decoupled on the input and output pins, as per the datasheet.

Other possibilities are that RF from your 1 watt transmitter is getting onto the supply line and upsetting the regulator, this will be due to poor layout/decoupling/screening.

JimB
 
when i used pin supply, the audio signal was quite nice . but when replace the supply by 780x for larger power in same PCB, it became so bad (tone "oooeee").i can't reduce this noise .
 
You can simplify the circuit by removing all the parts to the right of the 9v power source.

Never seen such a bazaar coupling, between VCO tank to drive output amp.

No way you would get 1 w output from that circuit.

2N2222 is an audio / switching device with Ft peaking at about 250-300 MHz at 20 mA. You will not get much gain out of it at 100 MHz.
 
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You can simplify the circuit by removing all the parts to the right of the 9v power source.

Never seen such a bazaar coupling, between VCO tank to drive output amp.

No way you would get 1 w output from that circuit.

2N2222 is an audio / switching device with Ft peaking at about 250-300 MHz at 20 mA. You will not get much gain out of it at 100 MHz.

the above circuit i simulated and its power is up to 1.2W . it has a little difference from practical circuit. i forgot some problem when post that picture.
 
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