Receiver dB Level

I have a pair of these transmitter/receiver modules.

The receiver is marked XD-RF-5V. The transmitter is marked 2008-8.

Is there any way I can figure out the dB level of the receiver.

I get very limited range from the receiver at 5V even with a 12V transmitter. I have read some units have very good range.

Does anyone know if the codes on the units have any particular significance. I have even seen some of these pairs advertised as super heterodyne... could it be?

Is there any way I can figure out the dB level of the receiver.

From the Arduino? No.

I get very limited range from the receiver at 5V even with a 12V transmitter.

With what kind of antenna? What length? What baud rate? What range do you get? What range do you expect? What code are you using?

I have read some units have very good range.

With proper antenna, proper grounding, proper baud rate, and for some definition of good, some people have claimed good range.

Does anyone know if the codes on the units have any particular significance.

I'm sure that the manufacturer thought they were significant.

I have even seen some of these pairs advertised as super heterodyne... could it be?

Personally, I don't think that there is anything super about those radios. You get what you pay for.

@PaulS: Noted and thanks for the input.

I have even seen some of these pairs advertised as super heterodyne... could it be?

The receivers you linked are not superheterodyne. They are superregenerative receivers. With good antennas on both units, you might get a range of 100-300 meters in the open.