C64 RF modulator
in [Commodore]
|
From: Paul Förster on 15 Sep 2009 13:05 Hi all, .... another question from the insane. :-) The RF modulator in a C64 seems to have 8 contacts soldered to the board. Does it have any influence on functionality or compatibilty if I solder the contacts off and take the modulator out, other than not having a TV signal, of course? Would anything NOT work if I did that? -- cul8er Paul paul.foerster(a)gmx.net
From: Clocky on 15 Sep 2009 19:29 Paul F�rster wrote: > Hi all, > > ... another question from the insane. :-) > > The RF modulator in a C64 seems to have 8 contacts soldered to the > board. Does it have any influence on functionality or compatibilty if > I solder the contacts off and take the modulator out, other than not > having a TV signal, of course? Would anything NOT work if I did that? You would have no video at all. The RF modulator does more then just the RF output, check the schematics.
From: Mr. X on 16 Sep 2009 02:21 "Paul F�rster" <paul.foerster(a)gmx.net> wrote in message news:7h9vrjF2rnlplU1(a)mid.individual.net... > > The RF modulator in a C64 seems to have 8 contacts soldered to the board. > Does it have any influence on functionality or compatibilty if I solder > the contacts off and take the modulator out, other than not having a TV > signal, of course? Would anything NOT work if I did that? This guy pulled his off the board but it still needs to be hooked up: http://www.bigmech.com/misc/c64mods/svideo.html This guy hacks up alot of stuff, including C64s: http://benheck.com/04-05-2009/commodore-64-original-hardware-laptop There's multiple versions of the C64, many schematics here: http://www.zimmers.net/anonftp/pub/cbm/schematics/computers/c64/ X
From: Paul Förster on 17 Sep 2009 12:42 Hi Ingo, > -i 'Why doesn't anyone look at the schematics first?' k .... you're right, sorry. -- cul8er Paul paul.foerster(a)gmx.net
From: bluebirdpod on 18 Sep 2009 09:11
Get a good de-soldering station if you plan on repairing many circuit boards, Its awful handy to just put the de-soldering tool right on the pin to remove the solder let it heat up and click the pump on to remove the solder, and as many have posted, you may need to cut the bad chip out and remove each pin one by one, Hell I had boards that I just wanted the chips out of, so guess what works really well, but you need to do it outside, get a propane torch and take your board out side, and put the flame on the solder side, it will ruin the board, if thats not problem, then heat up the board moving side to side in a small area, and let the solder melt, then you can usually just flip the board over and let the chips fall out, if the pins are bent to hold them in you can use a small screw driver to pry them out of their sockets, if you are too slow you may need to re-heat the board but it sure does work fast. Dont make your board get on fire, thats too much heat, it may blacken, but thats ok, dont get the pins red thats too much heat also, just move the flame quickly so you dont overheat one area. Hell I use to repair monitors this way, it was an easy fast way to resolder the whole board, but you have to make sure not to overheat any area of a board that you want to keep. If it starts getting black then you over did it, but on a canabalized board that you dont care about, then there is really no problem. De-soldering stations are either standalone, or combined with a soldering iron also, they have built in motor driven vacuum pumps with a vacuum line going to the de-soldering iron there is a momentary button on the side or if you have a gun type then there will be a trigger. Very Very valuable if you are repairing highly treasured old equipment like commodore boards. A decent desoldering station will cost about $250-$350. Just look on ebay, and get one with a small tip, you dont need to remove 50amp diodes do you ? Most of the C64's that I have had to repair have a bad ram chip in them, I like the C64 big board with 2 ram chips this has the old sid so sampled sounds work, and is full size but only has 2 ram chips and is easier to socket both and swap with other chips to test and repair, the easiest way to tell if you have a bad chip is they usually get very hot when powered on, you can usually find a bad kernal or rom chip this way, 6526's usually dont get hot but either the IEC bus does not work, or more commonly the joy ports are partly bad or completely bad. A lot of older C64's the PLA's go bad, well you can burn a PLA code into a eprom and use that, or scavange one from a doner board, torch time! -BBP |