http://www.8051projects.net/ Learn to make simple microcontroller projects, pic, 8051, avr and arm projects. download 8051 projects, tutorials, libraries, sample codes. join the microcontroller discussion forum and ask doubts regarding electronics. the best source for 8051 over internet. en-gb 2009-01-08T06:13:11-08:00 contact@nospam.com hourly 1 2000-01-01T12:00+00:00 http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 can any body please suggest me a method to determine the frequency of a tv channel without changing the hardware of televesion?? tnx in advance http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 ۞ TPS ۞ hi this may helpfull for you Radio Frequency SpectrumFrequency Use Cable TV Use 3-9 KHz not allocated 9-14 KHz long range navigation 14-535 KHz an assortment of fixed and maritime mobile radio, radio location, radio navigation, maritime radio navigation, aeronautical mobile, aeronautical radio navigation and mobile radio 535 KHz - 1.6 MHz AM broadcasting 1.7-54 MHz various amateur bands, shortwave broadcasting, industrial, scientific and medical usage, CB radio, and mobile radio 54-72 MHz TV channels VHF 2, 3, 4 Ch. 2-472-76 MHz Aeronautical navigation and astronomy 76-88 MHz TV channels VHF 5, 6 Ch. 5-688-108 MHz FM broadcasting Ch. 95-99108-135 MHz aeronautical navigation and communication 120-174 MHz Ch. 14-22135-144 MHz space research, land mobile radio 144-148 MHz amateur radio 148-174 MHz land mobile radio, government fixed mobile, paging services 174-216 MHz TV channels VHF 7, 8, 9, 10, 11, 12, 13 Ch. 7-13216-470 MHz an assortment of land mobile, amateur radio, government fixed and mobile radio, aeronautical, and marine radio 216-648 MHz Ch. 23-94470-608 MHz TV channels UHF 14 through 36 608-614 MHz space operations (there is no UHF 37) 614-806 MHz TV channels UHF 38 through 69 806-890 MHz cellular telephones 890 MHz - 3.5 GHz an assortment of radio location, land mobile and paging, aircraft navigation, amateur radio, aeronautical satellite, space observation, microwave ovens and maritime radio 3.5-4.8 GHz C band (Anik B, D, E) satellite downlinks 4.8-5.8 GHz various radio navigation 5.8-7 GHz C band satellite uplinks 7-8.5 GHz various uplinks and downlinks 8.5-10.7 GHz various radio navigation and location, including police radar 10.7-12.2 GHz Ku band (Anik B, C, E) satellite downlinks 12.2-12.7 GHz maritime radio navigation, and direct broadcast satellites 12.7-14.5 GHz Ku band satellite uplinks 14.5-275 GHz various EHF (extremely high frequency) allocations, many of them satellite usage http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay SHYAM wrote ...can any body please suggest me a method to determine the frequency of a tv channel without changing the hardware of televesion?? tnx in advanceWhat do you mean by.. without changing the hardware? Please explain clearly.. http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 ۞ TPS ۞ any idea to crack (info) DTH channel .i mean any one know what is channel selection procedure in DTH system http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay TPS you are a moderator.. you should not talk about cracking stuff and all http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam i have detected the frequency by placing a rf probe inside the tv above the tuner card .now i want to do it without opening the tv. http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay shyam, you need to make something like an auto tuner(like in Auto Tune FM), so when you get a good response signal that means you have got a channel and note the frequency. But i am not sure will this auto tune works without TV on or not.. i am sure it works.. after all its a frequency.And... you can test this thing also using an FM radio as TV frequencies start from 55-68Mhz something.. and FM works from 88MHz, so if you're lucky you can listen to a channel sound.. actually i did this experiment with my CAR radio.. and it works TV was on at that time http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 ۞ TPS ۞ SHYAM wrote ...i have detected the frequency of channel frequency? http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 ۞ TPS ۞ Ajay wrote ...TPS you are a moderator.. you should not talk about cracking stuff and all sorry , i used word "crack" instead of information i have corrected the post http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 abhishek_h it is possible to find the frequency of a channel. but in case of DTH, the data is decoded in some format so just finding the frequency is not enough. Have you noticed the time delay while changing channels? thats the time taken for decoding the data. ( that delay is constant. ie, DTH is 1-2 sec delayed compaerd to cable.) So even if u know the freq, its of no use. if you want to experiment with frequency, do it with cable service. I will try to post the pinout of the tuner module shortly. http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam well the project is something related to the trp rating of tv channel.I have obtained a project from a leading tv serial company,they want to place my device along with the tv set, in the homes of people of different sectors of society.now i have to use the device as a data logger and record the channel frequency that is being tuned at various time.as i already said the first part has been done by placing an rf probe over the tuner card ,inside the tv, now i wanna do it without opening the tv. http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay yeah.. you are right abhishek, the DTH channels are coded and you need a special authorization key to decode that data.. its encrypted... and whatever i explained in my last post is actually for cable TV. But why SHYAM is behind all this? please tell us about your project.. http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay oo... nice.. shyam.. this site is for students i never discuss company projects http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam yes ajay you are right,but i am ready to make the project open right from the hardware to the software part.may be some of the students too would find it interesting.moreover this is totally my idea , no committment as such to the company.All i want is to make this thing work. http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay well... i like open source projects.. and sure i am helping you.. well must say... your project is interesting.. and its good to log which channel is being watched more and at what time good statistical tool http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam i am attatching the diagram of the rf probe used.the probe is working fine when placed above the tuner card of tv 1189887533_2984_FT2214_rfprobe.pdf http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam the probe can be interfaced to an 8051 cpu or ARM (lpc21xx).the input is to the adc and the voltage can be decoded to get the actual frequency detected.if it is required i can post the 51 cpu schematic too http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay will be great if you can post hey i will add this completed project in the site.. of course with ur name http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam hi folks,my problem is still not solved ,by (schematic submitted) the rf probe, i can detect channel frequency but the probe has to placed inside the tv over the tuner card.how can i do it from outside the tv?? http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay did you try it on the wire? that goes from set top box to TV?check if its showing you some results!?!do you have a PCB for this probe? http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam actually i wasnt using set top box, but cable (cable tv).i'll see and post the pcb ... http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam here is the pcb layout 1190219077_2984_FT2214_rf_probe_layout.pdf http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay Thank you so much well if you are using cable TV line, then it will be hard to find which channel is tv tuned to. We need to find another way.. http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam ajay,if u think set top box will be easier,we will do it that way. http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay well i think so.. but i am not sure.. because as i think.. setop box will give u one frequency its tuned to..But if its a higher frequency and out of range of probe? as its not VHF/UHF its coming direct from satellite and receiver is at the dish, you will only get the IF frequency am i confused? http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 shyam as i said,i have tested the probe with cable tv.....i am still trying with the set top box...i'll let u know the progress soon.till then cant i just catch the frequency of the channel from outside the tv box?,even detecting frequency of horizontal sync pulses would do..is there a way i could amplify the gain of the probe?? http://www.8051projects.net/forum-t2214.html 2009-01-08T06:13:11-08:00 Ajay yep i was thinking the same.. but that will also lead to increase in the noise. so we need a filter circuit too for that.. but it will be worth to use.. also.. it will be better if we stick to something which worked already rather to move to something else which is untested unless we are end up with no way out!