computer in a radio


Supreme [H]ardness
Sep 6, 2002
i needed something to do while the forums were down and i didn't have a processor for my box (forums are back up but i still don't have a processor, so the project will continue)

i can tell you right now that this worklog won't be exactly full of pictures. i just started it and we are getting close to done with it, so there won't be much in the way of construction steps. my method of obtaining pictures isn't all that great either. so bear with me, and i'll get pictures when i can.

i was looking around and happened across a stereo (working) in my basement that wasn't in use. it belonged to my brother. i checked with him, and he said it was fine if i used it as a computer case. he also said he would help. we checked the physical size of the box, and it was big enough for the matx system that until now has been on my nightstand. (celeron 400, 256mb memory, linux)

so we got to work.

original plan:
1) remove the tape deck from the stereo
2) relocate the transformer
3) install motherboard in the base of the unit where the tape deck went
- wire sound outputs through the amp where the tape deck originally plugged in
4) leave 3cd changer/radio intact and still working.

now of course this didn't work, or else i wouldn't have said 'original' plan.

first problem - motherboard didn't fit in base (d'oh!) so we took out the cd changer and mounted the motherboard upside down in the top of the case. the power supply was placed on the base, and bolted down through two holers drilled in the top of the psu (it is upside down as well) the transformer was wired to the power cord for the psu, and the other end of the power extension cable we used was run outside the radio where the power cable had originally gone. so now there is just a power plug where the cable had run.

second problem - this lay in wiring the sound through the tape deck 'in's on the amp board, as the impedances from a soundcard and a tapedeck are different (high vs. low) and the soundcard is also already amped some. however the speakers for the radio are unpowered, so the soundcard can't drive them. still working on a solution for that (suggestions welcome)

now a third problem has arisen. the atx motherboard cable from the psu won't reach the motherboard in the top of the case. it is about 1/2" too short. does anyone know of a cheaper extension cable than the one on frozencpu? it is only $3.50, but the shipping makes it 9-10 dollars. not cool.

we painted the sides, top, and bottom of the radio black. the back is getting painted as well after we finish cutting holes for expansion cards in it, and the front will get painted as soon as we get around to masking it. the problem with that is that the radio/amp piece is screwed to the front and we don't want to take it off, but it will be a major pita to mask it completely. we will probably just wrap it in saran wrap or something (but most definitely not saran wrap b/c of the static and everything)

anyway, it is coming along OK, and i'll post pictures when i get a chance. (i'm on 56k as well so that doesn't work too well - uploading is slow) more later.
well, what do you know. me and my brother fixed the other two problems.

with the audio: turns out the amp had to think the tape was playing for it to allow output from the tape deck. we shorted the connection indicating that the tape was playing, and it works great now. in fact, i'm listening to mp3's on it now. i just need to cut the back to fit the aureal sound card i want to put in here so the sound isn't quite as crappy.

power cable: my brother and i found a bunch of cable of the appropriate guage in my dad's workshop, so we broke out the soldering iron and away we went. we lengthened the cable about 2 inches, and now it fits and all. good stuff.

the radio still works in it, it just gets EMI on the AM radio. time to get it a tin foil hat:D
i lost the antenna for the FM, so i just get static on it. o well. i'll just make a new one later.

i'll try to get pics this afternoon/ASAP. keep in mind that the front is going to get painted as well and the rest is getting another coat. probably. depends if i can bring myself to disassemble it or not.

we'll see. comments welcome, and sorry again for the lack of pics. (me has no digital camera to speak of, just a camcorder and a tv cap card)
ok... here's some of the pics i promised. (8 pics, ~62kb each, 492kb total, 640x480, low quality color) these are all 'after' pics, btw.

here's the front of the unit:

here's the back of the unit:

here's the aureal we're planning to put in:

here's the inside of the radio:

closeup on the atx extension we made:

closeup on the connector to the tape in on the amp/radio board:

here's the motherboard:

and finally here's where we reenabled the reset switch:

you're welcome! (sorry about the blurry pics) i'll put up more later after i do shielding (tin foil) and get it painted properly.

will no one respond??? i won't bite (much)!

anyway, i got the tin foil in on top of the amp pcb. there is a layer of brown papaer bag inbetween the pcb and the foil, so it doesn't short anything out. the foil is grounded to the case. the aureal has been installed, and the sound is now much, MUCH better. comments are still welcome.
hehe, that's quite nicely stealthed. that would make for a really nice mp3/divx box if you ask me :p
yeah that's what is intended for. it does mp3's fine, and xmms allows network control through ssh or whatever then typing say 'xmms --play-pause' which has the same effect as clicking the pause button (or play button if it is stopped)

i believe that mplayer will allow the same sort of control (starting the movie anyway) but i have to check on that. it also kinda runs divx's a little slow (damn celeron 400) but with framedrop turned on it is fine.

i'm thinking about putting a p4 or something in it, but then i'd need to get a fan for it as well.

we're also planning to rip out the old radio, put a 2x8 or so character lcd where the old lcd is now, and put a GOOD amp in it with a radio, and then probably wire the front buttons to the amp/computer. or course, that could be a problem because then the remote wouldn't work. but we'd figure something out eventually, i guess.
great minds think alike :p i've already begun (as in ~8 months ago) my pc-in-a-tv project, but i need to get a 15" 16ms lcd and some acrylic before i continue, heh. if you get a very large heatsink, you could probably get a decent overclock out of the celery. if its at least 600mhz, you should be able to playback divx stuff without many dropped frames. however, i doubt you'll be able to go above 550mhz with it.

as for the remote, i haven't yet found a way to keep any stock remote and wire the reciever to work with a pc yet. i tried this with a vcr already and couldn't find a way to do it.
well, i would overclock it, but the problem is that the motherboard is from an emachines (400idx) and it tops out at 400mhz celeron (no p3 support AFAIK) so there goes that idea. i'll probably try to scrounge up an athlon 900 or something along those lines in MATX form to use in it. the celeron is more of a proof of concept than anything else.

with the remote, all it does is volume control, which is useful because i can just hit 'mute' and it shuts up. we were trying to get the computer wired through the radio amp so that we could use the remote to make it be quiet.

but it's coming along. it gets nice and toasty now, but i have a 80mm stealth to put in it when i get a chance.
I was thinking of doing that for awhile.
But I didn't know if it will fit .
You make a remote reciever that works through a computer's serial port. It would work to start, stop, and control the volume on the computer side of the box rather than the actual amp circuitry. However i'm not sure about linux's compatibility. I know there's two programs called WinLIRC and Girder that will work together to accept inputs from almost any remote in windows. There's a guide here that I saw on the [H] frontpage a while ago. Good luck with your mod!
i've actually stopped work on this mod for now, cause i need to buy a lot of stuff on a very limited budget for this and my other computer.
here's the basic list:
>either a 5-8 port switch and 2 cat6 cables or a 100 (maybe 75) ft cat6 cable (not gigE yet, but may as well be ready) so i can get both computers on the lan in my room.
>video card (9000 pro doesn't cut it anymore)
>new side panel for my case (the old one is seriously screwed up... at least i can get one - lian li)
>2 120mm fans
>metal for a shroud
>motherboard (thinking nf7-s2g. but i'll see) because my a7n8x dlx sucks.
>possibly speakers (edirol ma-10d or so methinks)
>ibanez sr506 (6 string w/ active electronics) and a 4 string acoustic/electric bass
total for that stuff: way too much $$

so anyway i will probably finish it up before the end of the summer (get it hooked back up and try to get the remote thing going) if i can get a switch. and build a shelf for it. so it could be a while. but it isn't quite dead yet:p

but anyway. thanks for compliments/suggestions. it may yet transition to a win2k/xp box if i can't get the remote stuff working in linux (and i have a linux box anyway) later.
However i'm not sure about linux's compatibility. I know there's two programs called WinLIRC and Girder that will work together to accept inputs from almost any remote in windows.

The LIRC in WinLIRC means; Linux Infrared Remote Control. It's a Windows port of a Linux program, so it should work under Linux. You may have to pair it with XKB to control stuff with it, though.