RS232 to RF Input

[e.chain]

Hello to all, I am looking for an example circuit and asm source code to transmit hex data to a RF Input of a Cable Box with these settings:

14400 BaudRate
StopBit 2
DATA 8bits
Parity Odd

Frequency 106.5MHZ

 

[bananasiong]

You use FM band to transmit? Isn't it illegal?

 

[suby786]

RF input of a cable box?

RF as in wireless communications or cable as in cable TV?

Im interfacing a PC - SERIAL/RS232 to a a wireless FM transciever device... then on the PIC side, i have another transciever device with its rx/tx pins tied to the PIC rx/tx... is this what would help you?

i send hex values from my pc and my pic picks it up... meters and meters away

 

[gramo]

Here’s a great RF transceiver, and its $33 Australian

https://secure.oatleyelectronics.com//product_info.php?products_id=388

Of course you can buy much cheaper RF transmitters and receivers, but as a transceiver, and its features, its not a bad product

 

[Nigel Goodwin]

Here’s a great RF transceiver, and its $33 Australian

https://secure.oatleyelectronics.com//product_info.php?products_id=388

Of course you can buy much cheaper RF transmitters and receivers, but as a transceiver, and its features, its not a bad product

Nice little normal licence free module, but what has it got to do with this thread?.

 

[gramo]

Its RF, capable of the required data format (as the module does all the FSK encoding), long range, built in standby mode, 2 channel, 20Kbit/s data rate, reliable and a single piece solution for bi-directional data.

I have no idea what a cable box is though...

Soo, its prolly no good for him

 

[Nigel Goodwin]

Its RF, capable of the required data format (as the module does all the FSK encoding), long range, built in standby mode, 2 channel, 20Kbit/s data rate, reliable and a single piece solution for bi-directional data.

Didn't you read the "Frequency 106.5MHZ" part?.

I have no idea what a cable box is though...

Cable TV box - perhaps you should fill your location in?, then people won't assume you understand common things like that (and cable isn't even common in the UK).

 

[gramo]

Cable TV box - perhaps you should fill your location in?, then people won't assume you understand common things like that (and cable isn't even common in the UK).

My bad, my bad, stop drilling me and help the guy out

 

[e.chain]

RF input of a cable box?

RF as in wireless communications or cable as in cable TV?

Im interfacing a PC - SERIAL/RS232 to a a wireless FM transciever device... then on the PIC side, i have another transciever device with its rx/tx pins tied to the PIC rx/tx... is this what would help you?

i send hex values from my pc and my pic picks it up... meters and meters away

That could help a lot, somebody months ago told me something about this but didn't explain me in deep. It has a long range of 89 to 108 MHZ, I think that could solve my problem. The only thing I am thinking of is where do I have to solder the RF coaxial cable, maybe to the antenna of the wireless FM transmitter?.

 

[suby786]

the RF coaxial cable i take it your talking about the wire between the antenna and the transceiver???

The RF input to the transceiever is the antenna, and if your using cable then yes 50 ohm coaxial cable will suffice, if ur doing it on pcb, like I am, i have a SMA PCB connector, which connects to the input pin of the SMA.

Im using 900MHz band but i dont think that should effect you. Have you got an actual device for this?

 

[Nigel Goodwin]

That could help a lot, somebody months ago told me something about this but didn't explain me in deep. It has a long range of 89 to 108 MHZ, I think that could solve my problem. The only thing I am thinking is where do I have to solder the RF coaxial cable, maybe to the antenna of the wireless FM transmitter?.

Perhaps you should explain in more detail what you're trying to do?.

 

[e.chain]

You use FM band to transmit? Isn't it illegal?

This is the frequency the cable box uses, I need to repair this box, it is the only way, the other way is to open the box and cut the data jumper and that is illegal.

 

[e.chain]

Perhaps you should explain in more detail what you're trying to do?.

I have the software to send the hex files to the Cable Box, I can do it direct to the data link of the box, but I will have to open the box to do it and that is illegal, so I was thinking in something to do it via the RF connector this is the way the cable companies fix the cable boxes. I am attaching a picture of what I think I can do.

 

[Nigel Goodwin]

I don't see as opening the box is any more illegal than doing it this way?, either the box is your's (and you can do what you like) or it's the cable companies, and they should come and repair it for free.

However, this doesn't sound like 'repairing', this sounds more like wanting to make illegal modifications to the box, presumably to steal more channels?.

 

[e.chain]

No, No, modding the box to get free channels is one thing, and can be easily done with a test chip, what I want is to get the box out of EA ERROR what means Invalid Serial Number Entry or Bad Rom Checksum, this is a fatal error in analogue cable boxes that happens when the 3v battery dies or when somebody opens the box and plays with the wrong part.

 

[Nigel Goodwin]

No, No, modding the box to get free channels is one thing, and can be easily done with a test chip, what I want is to get the box out of EA ERROR what means Invalid Serial Number Entry or Bad Rom Checksum, this is a fatal error in analogue cable boxes that happens when the 3v battery dies or when somebody opens the box and plays with the wrong part.

So why don't you have the cable company come out and do it?.

 

[e.chain]

No, they will have to send the unit to a Jerrold Tech Facility which is not in my country and then they will charge me the cost of shipping and repair, I already called my CACO but since they are migrating the boxes to digital they want me to buy a digital box instead.

 

[Nigel Goodwin]

No, they will have to send the unit to a Jerrold Tech Facility which is not in my country and then they will charge me the cost of shipping and repair, I already called my CACO but since they are migrating the boxes to digital they want me to buy a digital box instead.

So it's YOUR box and not theirs?, so take the top off - it's YOUR property and you can do what you like with it.

 

[e.chain]

Yeah, but in the HeadEnd they do it through the RF connector not through the data link, there must be something special in this, since it only can be repaired in a Jerrold Tech Facility that is why I don't want to open the box, anyway will try to do it through the data link.