Now, I've not done proper, practical Electronics since it was compulsory in Years 7-9 at school.. Although I did do the theory at GCSE and A-Level in physics. Albeit only analogue electronics, I have a limited knowledge of digital which I picked up through personal research. It's still something I'm really interested in, and I'd like to get more into it by perhaps making a small device of my own. What I'm thinking of is an FM transmitter for my Walkman so I can use it in the car. I was just wondering if anyone could help me out with a few things. Like whether I should use the proprietary USB or 3.5mm jack to connect the transmitter, or whether I could even do it. What parts would I need? Could I get them from somewhere like Maplins? Would a small LCD to show the frequency be too much for a rookie like me? Like I said in the thread title, I'm only thinking of doing it at the moment.. I've not committed yet, I was just wondering if it was plausible.
It would be easier to use the 3.5mm jack rather than the USB, because you would have to build a DAC form the transmitter, plus potentially you would have to program some PIC's for it. ( i am no expert, just saying what i imagin to be) I know maplin sell electronics projects and i believe they had a FM/AM reciever, but for a transmiter i cant see what would be different, just a bump up on the power source to transmit, and a line in. To make life easy i would 'fix' the transmission frequency, possibly in the AM range, as most of the FM range is packed and you would only get interference. Plus car stereo's can only scan between certain FM Frequnce ranges, as the police band and 'other' bands are further along it.
Thanks for the help.. But how would I go about reversing a receiver kit so that it transmits? Or do I not really need to do anything?
You can get cheap fm transmitter "bug" kits, heaps everywhere and even heaps of free schematics on the web that you can build from scratch, but i wouldn't bother etching my own board since the kits are so cheap. I've only seen mono ones, but they have a little variable capacitor you can turn to basically choose whatever frequency you like on the fm dial, and within say ~50 meter radius a small cheap fm bug will take over any radio station. So if you take over a populat station, any car next to you that is listening to that station will now be listening to your music You can just connect the line out/headphone plug to the microphone input of the bug kit, with a voltage divider to reduce the relatively huge volume compared to what a little microphone produces, and you have a mono fm transmitter walkman. The bug could take power from the car and all you would see is a cord coming out from wherever you want in the car to your walkman, or even hide the lot. There might be stereo bug kits out there? But car stereos are so cheap these days, i'd rather just get a modern deck that has mp3 & sd and/or usb. Not as cheap as spending $10 or less on a bug kit i guess.
You're failing to see the point. It's not so much the product at the end that I want, but the experience of building my own product. It's just a project to keep me thinking and not going insane.. My experiences at Uni have been somewhat lonely and boring.. if I've got something to think about, problems to overcome.. It'll keep me occupied. I mean, who wants to actually DO their Uni work?
You may want to have a look at: http://mikeyancey.com/FM-Stereo-Broadcaster.php The above link is good if you want to build something seriously geek-worthy with LCD's and digital control. Any good to you?
Bookmarked... I'll have a better look at it later when I've got time, and aren't so tired.. Thanks for the link.