Help me to make a 800 Mhz oscillator

[twilight]

For my project i need to make a osc. for 800 Mhz.

I want to use the J310 fet, bud i cant find out the max freq. of this device?


Please help me, masters...


thnx, greetings Fred.

 

[IanP]

Re: Osc 800mhz?

The J310 may not work in an 800MHz oscillator ..
What you need to do is to generate ≈260MHz(160MHz) base frequency with the J310, and then multiply it by3 (5) ..
Here is an example:
https://www.qsl.net/yo5ofh/projects/2400mhz_signal/13cm.htm

Regards,
IanP

 

[E-design]

Re: Osc 800mhz?

Depending on your application, a 800Mhz osc can be easily made using a common MMIC amp (MAR series from Minicircuits and others) and resonator. For the resonator you have a wide choice according to stability and noise performance: ceramic, lumped-LC, coax line, microstrip etc.

 

[twilight]

Re: Osc 800mhz?

Manny thanks for the reply's.

I have the schematic, here as attachment, its from an orginal transmitter from Italy. This transmitter works on 800-900 Mhz.

Is this oscillator working streat on 800Mhz, or is it a mulitiplier...

Thnx Gr. Fred.

 

[throwaway18]

Osc 800mhz?

I can't tell from that schematic. We don't know the inductance of the strip lines.
If there is a mutiplier then it is further down the circuit. The part of the circuit you have shown just contains an oscillator and a buffer amplifer.

 

[BigBoss]

Osc 800mhz?

There must not be multiplier itslef. If the tank circuit is resonated at 2nd or 3rd harmonic, the oscillator may work lower frequencies.Because every oscillator creates harmonics less or more...

 

[artem]

Osc 800mhz?

i have seen wheather forecast ballon with one element telemetry transceiver . I did not know the frequency but its output was directly connected to 1/4 grond plane antenna about 8 cm length ~ 32 cm wave length.
may be i am wrong.

 

[twilight]

Re: Osc 800mhz?

thnx for the idee's...

i want to build this j310 schematic, and whe will see whats happening...


Second choice is the bf970 oscilator, this one runs well on 800mhz... bud makes some noise....shame... (and obsolete component..)


GR, Fred.

 

[kevinj]

Re: Osc 800mhz?

check it. vco.