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Need help with an antenna...

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Heresy

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I am using this chip (**broken link removed**) and this antenna (**broken link removed**) to build a simple RF receiver that will control a logic circuit. Right now, I have everything on a breadboard and am using a working transmitter to test it out. However, I am not getting anything from the chip.

I checked the ground, Vcc, and address bits to make sure everything was hooked up correctly. It looks like it is, and after talking to the company that makes the chips, they are telling me that the antenna is probably the culprit. Basically, they told me that the chip should be put on a PCB and a decent ground plane should be used to ground the antenna to reduce noise. I am looking to see if anybody can help me get this circuit up and running. Below is what I have so far (messy, I know).

**broken link removed**

**broken link removed**
 
You can't expect RF circuits to work on breadboards - they are completely useless for this!. Even low circuits RF circuits aren't likely to work, and you've no chance at UHF.
 
Here's a piccy if one I made earlier!
This gizmo works on 914mhz, and has been used upto about 300metres with a 10mw transmitter into a 1/4 wave dipole antenna. :D
 

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No offence intended but perhaps you don't have enough experiance to build a transmitter; the fact that you've attempted to do so on a bread board suggests you haven't learned about the essensial principles such as board layout and parasitics which are key in building a working design.
 
Gayan Soyza said:
Hi Heresy remove all tha parts & assemble it again.You must follow breadboard principles.....Specially the power lines.
note that the breadboard is disconnecting the 4 power lines in the middle.
First of all, not all breadboards have their power rails split like this. the ones I have that look EXACTLY like the one pictured do not.

Second, did you read the rest of the replies? He should not be using a breadboard at all!
 
Perhaps no one's shouted shouted loudly enough.:D

Don't use bread board for frequencies higher than about 10MHz!

Your RF circuit won't work on a bread board!
 
It might work on the breadboard if it has a supply bypass capacitor right at its supply pins. Its battery is pretty far away.

It is a complete radio module. The only things external are its power supply, its antenna and its setup switches. All the RF stuff is inside it.
The datasheet says that a perf board makes it have "horrible" performance.
 
Basically, they told me that the chip should be put on a PCB and a decent ground plane should be used to ground the antenna to reduce noise. I am looking to see if anybody can help me get this circuit up and running. Below is what I have so far (messy, I know).
And your reason for ignoring their advice?
 
Shax said:
Here's a piccy if one I made earlier!
This gizmo works on 914mhz, and has been used upto about 300metres with a 10mw transmitter into a 1/4 wave dipole antenna. :D

Thats a sweet lookin PCB. I wish I could make um look that nice.
 
evandude said:
First of all, not all breadboards have their power rails split like this. the ones I have that look EXACTLY like the one pictured do not.
Hi evandude today I noticed that. His power railings are not splitting. My ones differ. May be some other problem.
Second, did you read the rest of the replies? He should not be using a breadboard at all!
Can he make his own PCB for this circuit with correct measurements? It will be more complicated than he is trying to rescue the circuit from the breadboard.
If he can make a PCB then it will be fine.
 
That antenna is probably really unhappy with a couple dozen pF of breadboard fun hanging off of it.

He might have a chance if wires the antenna *directly* to the pin and not through that screw terminal jack (?!). That and some well grounded copper tape/clad board directly under the module probably wouldn't hurt, but the reception with that getup is going to be *lousy*.
 
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