SparkFun Forums

[Lupe]

Hello all, I have some questions on rf designs. I have a supply of receivers and transmitters here are the part numbers (KESRX01 290 - 460 MHz ASK Receiver ) and transmitter based on (RFM-RO2100 saw resonator). My questions are 1. Since both of these circuits use PIC microcontrollers can I remove the PIC's and use the receiver in my project with an AVR micro since I have the STK500 and some AVR's. I think I can do this with the receiver since I can just pick up from the data out pin without a problem. 2. I am not sure about the transmitter since it uses a resonator, so what can I do about that. Also since the frequency is set to 295MHZ how can I go with a different transmitter that will work with this receiver. I am trying not to build my own circuits since I have plenty of these, any idea's on how I can use these circuits would help. Thanks Lupe.

[riden]

The receiver is able to operate anywhere in the 290-460Mhz range with the exact frequency determined by the resonator on the board (Google KESRX01 for the datasheet). It is possible you have a receiver tuned to 295.05, that could make sense if you got these as pairs. I didn't see a reference to the transmitter, but most of the ASK/OOP units operate by powering the transmitter with 5 volts or so (check your datasheet) and keying the "tx" with the data. Replacing the PICs with an AVR device should work just fine, although you need to code your own transmit and receive protocols.

You may have everything you need to get things working or you could replace the resonators to move the pair to another frequency. Which reminds me to ask you if 295.05Mhz is a legal frequency in the country where these will be used. In the US, this frequency is in the mobile/satellite mobile spectrum, but I couldn't find any specific mention of this frequency. It may be that a license is required to operate on this frequency. It is very important to verify that before using these devices, if you want to avoid trouble.

Perhaps someone can comment on the use of 295.05 MHz as this is a new one for me.

[Lupe]

Thanks for your response. I found some Zarlink transmitters like the one you are talking about where you feed the data in to it, (IC type). However they are obsolete. My goal is to use what I have but I don't think it would be as easy as disconnecting the PIC and supplying my own data in from my micro. Would it be better for me to use the transmitters I have or to find a transmiiter that can work with my receiver which is a 295.05 MHZ. I assume it is legall to use because they are widely used here in the USA. The recievers and transmitter are used in the automatic gate industry and I have been working with them for about 10 years, they are available at most fence/gate supplier and through the internet. If you or someone can give me some direction here I would really apprciate it. Question, what is the difference in using a resonator with a micro and a single chip IC (ASK transmiiter). Thanks again. Lupe