Hello all!
I am trying to make a RF meter module for my Arduino using the AD8319. I would like to be able to read the whole available frequency range from 1mhz to 10ghz, but it seems like I need different value components for different frequencies 
.
How would I make it work for all the frequencies without having to change the values of some of the components?
Thanks in advance!
Here's the data sheet:
I would suggest waiting a few years to find the chip of your dreams. If you want to use this chip using analog switches to switch capacitors may solve the problem, you might consider that. The filters are tuned circuits, consider the cost of putting accuret capacitors of those values on the chip would be expensive is there processos will allow it. You can post an annotated schematic of your proposal, not a frizzy picture.
Thanks for the response @gilshultz !
Dang.
I thought of that also, but I wasn't sure if the analog switch would interfere with the function of the AD8319.
I think I got one! How's this?
The circuit matches the AD8319 circuit in the data sheet as closely as possible.
Analog Switch data sheet (74HCT4051):
Edit:
I meant to wire the RF Output Voltage to the Arduino Analog 0 on my schematic.
Did you account for the ~75ohm resistance of the 74HCT4051 switches?
Leo..
Oh! Its 75Ω? I thought I read that it had a 10Ω on resistance .
Great Schematic, Thanks. You could use N-Channel MOSFETs for switching the resistors. You could also ground S2 on the 4051 as you are only using 4 inputs freeing D4. Try using D4 to replace the zero ohm resistor if you do not use MOSFETs If you use the analog switch you need to add the ~80 Ohms in the form of a resistor (varies with VCC from about 60 to 80) to the Analog switch resistors you put in the select section. Check the OEM data sheet for your exact part to be sure. If you are supercritical on the resistance value you would need to measure the analog switch resistance through each channel. I would not expect much change. You will need to power the switch and select the channels to do this.
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