cctvmeister 0 Posted October 26, 2007 We have produced 2.4GHz frequency wireless intercom door phone, they transmit analog signal in 4 different bands(2.414, 2.432, 2.450 and 2.468GHz), The faulty is that they are interfered each other when installing two or more in front door and back door at same time. and it transmit less than 40feet through walls. I wonder if we use DSP(digital signal processor) replacing of analog processor to settle down interference, and which way make it more far under not changing power capacity(100mW in transmitter and receiver, it's our radio law). Share this post Link to post Share on other sites
zmxtech 0 Posted October 31, 2007 DSP will cost way to much for this simple application. re-design the RF front end, limit the IF bandwidth and change to 5.8ghz ISM oh and those black antennas sticking out -yuck make them internal maybe add a few IR leds to help in low light -and use a good sony HAD sensor my 2c z Share this post Link to post Share on other sites
rory 0 Posted October 31, 2007 Looks like it has 6 IRs . though I imagine it doesnt have an IR Cut Filter so that image on the screen is probably not real I figure the external antenna gives it longer range? Maybe have internal then just an option for an additional antenna, use antennas like the ones for Linksys routers so we can buy them anywhere. 5.8? Would be nice, maybe more expensive though? Would be nice if it had 2 Cameras, a seperate color and a seperate BW, then the IR, a photocell to switch to BW IR mode, and a pot level to adjust the amount of IR and another to adjust the photocell switchover ... now maybe we are getting too expensive though but .. someone might want good quality. Ahh, perhaps also look at WDR like Pixim? Share this post Link to post Share on other sites
cctvmeister 0 Posted November 7, 2007 thank you. but we decide to give up because it is more than our budget to cintinue. Share this post Link to post Share on other sites