433MHz Voltage Requirement

Hi all,

I am aware that both PICAXEs and 433 MHz modules (specifically the Mapolin Tx/Rx pair) can be run from 3V (2xAA batteries), but does anyone know of the consequences with regard to data transmission? i.e. is there any increase in signal loss compared to 5v power?

I can't check this myself as I'm not at home. Just want to get a headstart on a new project.

Probably no "signal loss" (usually meaning attenuation between transmitter and receiver).

However, the transmitter's power output may depend on the voltage used and the receiver's sensitivity may be affected by the voltage used. Depends on how much regulation is in the modules...

John

Is this part number VY48C (the Tx Rx pair)??

If so, you'd better just have a check of the part number of the actual modules.
The DATA SHEET specifies different part numbers for 3V and/or 5V operation for the Rx module.
As the catalogue says, the Tx will work 2-14 Volts , but NOT the Rx module, so a little ambiguity in the catalogue spec...

Of course, if its a completely different catalogue number then forget the above.

If it is the same, here's the DATA SHEET:
http://www.maplin.co.uk/Media/PDFs/vy48.pdf

Yeah, it's the VY48 pair. For some reason (I was an employee there for a year), I don't trust Maplin stock. Even if it's not a Maplin product.

The transmitter will be in a handheld unit, so that's the only part that will be on 3V. The receiver will be on 5V from a regulated 12V SLA battery, so no problems there.

I think it'll be fine. Maximum distance will be about 20m anyway.