upneet

Hi. Again the project has changed but now i am going to post lots and lots of details because my project demo date is nearing and i need lots and lots of help ;) now wer r using four sensors one pH sensor from sensorex, one local humidity sensor and two temperature sensors pt100 and lm35 we are interfacing this to atmel microcontroller 89c52 which is driving LCD. we are getting digital output from this which we are transmiting using RF i am using ICs from www.mdclrf.com they are working fine. at the receiver end we are giving this received signal to com port of pc using rs 232 and Max 232. I want some VB code which can display this information. I am uploading all the info that i have thanks for help prem.asm is the code that i have downloaded from the internet but its not working. any idea how we can test that? BD.zip CODES.zip

I am getting 4800bps data from my RF ic. Now i want to connect this to my computer I know i will have to use some ic like max 235 or something then i would like to use com port and some vb programming to get a good user interface which will show all the details about the sensed values with bit of graphics like graphs and all can you please send me some information about it or any sites where i can get the codes and info thanks u one and all

No i was not hibernating these days! my project plans have changed drastically NOw i have to interface four sensors ph, temp ( lm35), light sensor ( from optical mouse or something) and humidity sensor if possible to a pic ( mostly pic 16f877) or similiar then i have to display this on led or lcd display and if this gets over then transmit it wireless and next stage is to receive this signal and interface with pc so that it can be displayed using java and VB. extremely tough project i need all ur help thanks

hi i saw that site it was helpfull downloaded few stuff which i will study. But the problem with foreign site is that its costly and payment is tough. So here is an indian site www.mdclrf.com its cheap and good and i am planning to use the following ics MDT 4 - 433.42 Mhz High power transmitter 1000 feet and MDR 422 as receiver will it be ok? it uses serial mode transmission so is it ok or do i need to make any changes? everyone is against me for using wireless is it sooooo tough? please help!!

hey guys/gals i have started working on rf part i was india centric help. I would like to know which frequency will be most suitable for my application.i want to transmit the signal from temp/ph sensor the range is less then 100 meters i wont it as simple and cheap as possible. I dont wont to go in for licencing. Is 900mhz ok? can I get ready made ics which work as transmitter and other as receiver? thanks for ur continued support

thank u kevin and MP for ur support. I was working on both wireless n RS 232 and RS 422 methods the problem with RS 232 is its noise immunity and it cant be used above 50feet and the problem with RS 422 is its cost. The problem with wireless is licencing because the police wireless operates and i have to find about licencing though 900MHz can be used without licencing. As MP told i saw that site and it was very usefull. I have finalised some main things about my project I want the range of wire or wireless to be around 100 meters even a radius of 50 meters will do. I have to finish my project in 20000 rupees ( around 200$) this includes cost of wireless/wires components and temperature and conductivty sensors. plus all other expenses ( unless someone sponsors my idea) I know the going will be tough but with ur supports its always going to be easy thanks everyone for ur support i have gathered lots of info if u want just mail me at [email protected]

hi friends I have my major project this time. We have to make project on farming ( electronics in farming!!) I had built an online pH meter last year. Now i m interested in making a unit which measres pH, conductivity and temperature and transmits it to a computer using either wireless technique (900MHz) or RS 422. Then i plan to use java and VB to make software which will plot all the things in real time and do all the things like sending mail, sms if certian temp exceeds, switch on a fan if temp exceeds and all that stuff. I live in gujarat india can u guide me the best place to get all the parts for that. thank u friends

thanks dude i think ur idea is great will let u know if i need any further help :)

if i wanted to use RF there was lots of problem with respect to licencing. then I had to use 900MHz one used in cordless phone but to finish everythiiing in three months is very complex now i plan to use RS 232 hope it works

hi friends, I searched for some IC's provided by analog device. Some IC's for modulation/demodulation, receiver, transmitter, transreceiver were real good. I think i will be tring for 900MHz. I live in India. Do u think i will have to get licence and all that stuff?

i have completed the pH part the sensors output is in mV range thus i amplified it using op-amp circuit and then displayed it using IC 7107 the o/p of temp sensor is also in vtg now i want to tranmsit this so that the computer withint 100meters can receive this signal (wireless) i dont want to indulge in licence and all because timeperiod is less so wat do u suggest? thank u for ur help

but the sensors will not be connected to computer they will be on the field then i need to transmit the data using rf to the computer which will demodulate and do the work my area of intereste is RF transmission

Hi I have to do a major project in three months. I have a idea as follows. we want to make a unit which measures pH, Conductivty and Temperature of soil then i want to transmit this data using RF to a computer is it possible? please help i plan to buy good sensors and then using RF i want to transmit it to a computer then i will make a software using java and vb which will plot the graph of all the values and stuff like that please help i have got a very short deadline u can contact me at [email protected] thanks u very much

dude i am planning a similiar project its like we measure pH, conductivty and temp on farm using some readymade sensors and then i want to wirelessly transmit the data to a computer which is situated at a distance. I m interested in RF communication is it possible> if u can help then please reply at [email protected] thanks