Need help with building RF transmitter and receiver

[johncsl82]

Need help for a project

hi

I need some schematic or "how to build" a list of item below:

1.AM RF transmitter and receiver amplifier
2.AM RF transmitter and receiver changer or controller

I try to build rf transmitter

**broken link removed**

but it didn't work

The conclusion of this project is to build a portable Walkie-talkie using RF

PS: I don't know anything about E&E

 

[kleinesmurf69]

Re: Need help for a project

Do you have any experience in RF/ electronic design?
This circuit should be very easy to construct since it seems to be a kit provided by Velleman. hxxp://www.velleman.be
Perhaps you could order and construct it. It will be a good exercise and you can do some measurements.

Best regards.

 

[eltonjohn]

Re: Need help for a project

That CIRCUIT is not an AM but a FM .. ok ]
try to debug it by
1) see if you did everything ok ,see if you have RF being emitted
this transmitter is supposed to work in FM .. with the help of a FM radio .just scan all the band an see if you notice a hum . or the light of the FM radio comes ON signaling a CARRIER present .. .If a particuliar signal appear in some form of noise .tap the Transmiter to see if that is heard on the radio .. If it does .great
you are in good shape .now your problem is on the MODULATION part ..
This ciruit modulates FM with the help of a VARICAP diode .this is a PARTICULIAR diode .Don't try to replace it with a standard diode because it won't work
this diode changes its CAPACITANCE in function of the voltage provided by the mic amplifier transitor ..

Ok i hope it helps good luck !

 

[johncsl82]

Re: Need help for a project

geeez

I don't anythng about electric & electronic............

I think i need some recommendation for PCB layout system and RF simulation software...........

 

[metal]

Re: Need help for a project

Hi

For the PCB layout, you may try using PROTEUS, or EAGLE software.

Regards