Anyone familiar with the IBM 5150

[jeremysart]

I have an IBM 5150 with a CGA adapter, which has an RCA composite output to hook it up to your TV if you did not want the CGA monitor (which I do not own).

 

I have tried hooking it up to three TVs now with no luck. I have tried using a couple different switch boxed, and one of the female RCA to male RF adapters, on both LCD and CRT televisions.

 

The Computer boots up for sure, when I turn it on it hums, for about 30 seconds, then the light on the 5 1/2 lights up and you can hear it booting. On the LCD I just get "NO SIGNAL!", and on the CRT, there are lines like scrambled porn on HBO, but you can tell something is there. And when you switch the machine off, or unplug the RF cable, it goes to fuzz.

 

Am I doing something wrong? Is it a video card problem? What do you think?

(please dont suggest getting a monitor, the 5153 CGA Monitor is impossible to find, and from what I have read, the RF output on these machines is perfect.)

[jaybird3rd]

The CGA card that came with my 5150 has both TTL (the 9-pin monitor connector) and composite video outputs (the RCA jack), and I've used the composite output with one of my 13-inch CRT televisions successfully. Do you have a conventional TV to test it on? That might tell you whether it's a problem with the card or whether the signal is outside the LCD televisions' range. Also, are there any DIP switches on the card? I seem to remember that one or the other outputs could be disabled or reconfigured through the switches, but my memory is hazy.

[Ben_Larson]

it says on Wikipedia that you need an external RF modulator:

 

When the CGA was introduced in 1981, IBM did not offer an RGBI monitor of their own.[6] Instead, customers were supposed to use the RCA output with an RF modulator (that they obtained separately, from a third party) to connect the CGA to their television set.

[Ben_Larson]

it says on Wikipedia that you need an external RF modulator for what that's worth:

 

When the CGA was introduced in 1981, IBM did not offer an RGBI monitor of their own.[6] Instead, customers were supposed to use the RCA output with an RF modulator (that they obtained separately, from a third party) to connect the CGA to their television set.

[monzamess]

Yeah, make sure you're connecting the computer output straight to the TV/monitor's composite input; don't mess with the RF adapters, switch boxes, etc. If you have an LCD TV or a CRT TV made in the last 10 years I can't imagine it wouldn't have a composite input. You only need the RF adapter if you're connecting to the antenna/cable input, and you only do that as a last resort in case the TV doesn't have a composite input, because the signal sucks.

 

I've done this in the past with no special steps or dip switch settings and it just worked, but that was at least 20 years ago, so I'm not sure what else to suggest. This is a worthless reply, sorry.

[Rybags]

Sounds like the Sync signal isn't coming through.

 

You'd want Composite Sync - so if there's DIP switches there might be options re how sync comes through.

[nathanallan]

Sounds like the Sync signal isn't coming through.

 

You'd want Composite Sync - so if there's DIP switches there might be options re how sync comes through.

Right, the dip switches may even be inside the computer on the mainboard or CGA card.

 

I wish I had that computer, they were really neat machines and a part of time travelling history. Jon Titor has one!

[jeremysart]

Yeah, make sure you're connecting the computer output straight to the TV/monitor's composite input; don't mess with the RF adapters, switch boxes, etc. If you have an LCD TV or a CRT TV made in the last 10 years I can't imagine it wouldn't have a composite input. You only need the RF adapter if you're connecting to the antenna/cable input, and you only do that as a last resort in case the TV doesn't have a composite input, because the signal sucks.

 

I've done this in the past with no special steps or dip switch settings and it just worked, but that was at least 20 years ago, so I'm not sure what else to suggest. This is a worthless reply, sorry.

 

Your reply was far from useless, I used the yellow video jack from my DVD player, and sure enough, clear as day on input 1- "IBM PC BASIC" Thanks! Haha! I have had this computer for so long, and now I can finally use it!

 

*EDIT*

Does anyone have a copy of MS-DOS on Floppy?

Edited February 23, 2010 by jeremysart

[monzamess]

Sounds like the Sync signal isn't coming through.

 

You'd want Composite Sync - so if there's DIP switches there might be options re how sync comes through.

Right, the dip switches may even be inside the computer on the mainboard or CGA card.

 

I wish I had that computer, they were really neat machines and a part of time travelling history. Jon Titor has one!

 

I had a 5150 I picked up at the tail end of their useful lives (maybe the 386 was already out by then). Played with it for a while and sold it to some guy who worked for IBM. That was my first UPS shipping fiasco (no online tracking back then). Although I always wanted a real RGB monitor, one of the upsides with being stuck with composite was that I could properly play the few PC games that took advantage of artifacting to get 16 colors instead of those nausea-inducing 4-color modes. There were even a few games that used a "hidden" CGA mode of 160x100x16 colors (yes 100 not 200). You needed a real IBM CGA card or very close clone to get those to run.

 

On the DOS disk... again I'm no direct help. You can download disk images of most DOS variants that you can write to real floppies. Problem is, you need a "modern" PC with a 5.25" drive, and a blank 360k floppy, to make that go. Even then you might run into subtle errors because the "modern" 5.25" drive is a high density 1.2MB drive and they don't always deal well with 360K disks. I *just* dismantled my last PC with a 5.25" drive. It's in storage somewhere.

[jeremysart]

On the DOS disk... again I'm no direct help. You can download disk images of most DOS variants that you can write to real floppies. Problem is, you need a "modern" PC with a 5.25" drive, and a blank 360k floppy, to make that go. Even then you might run into subtle errors because the "modern" 5.25" drive is a high density 1.2MB drive and they don't always deal well with 360K disks. I *just* dismantled my last PC with a 5.25" drive. It's in storage somewhere.

 

I'll give that a whirl and see what happens.

Thanks again everyone for the replies.

The computer is running and in good operating condition, I'll probably be hitting eBay or the marketplace to see what software I can get for the beast.

[nathanallan]

@jeremysart,

 

It's great that so many people are loving older computers, I started with vintage computers then got into gaming (long story).

 

If you can't find a 360K drive, I have one. It's a Toshiba external that you'll have to yank the drive from, and I'll even keep the outer shell if you don't want it to make it lighter. It's steel and pretty darn heavy, that's an option. But I'll have to test it first, I can get on that tomorrow (got a perfect machine up and running to test it on, a P133 that has win95 on it). I can let it go very cheap, or even as a trade.

 

PM me if interested.

[jaybird3rd]

Does anyone have a copy of MS-DOS on Floppy?

I have an original set of PC-DOS 3.0 floppies that I can copy for you. In my opinion, it's useless to try to run a version of DOS much newer than that on the original IBM PC: the newer versions were designed for machines with a lot more RAM, and would use up too much memory while offering features that the machine is too old to take advantage of anyway. Even version 3.0 is somewhat newer than the hardware you have: if I remember correctly, DOS 2.x was the standard DOS that was used with PC/XT class machines; 3.x came along with the IBM AT and 286 clones, though it works just fine on the older machines.

[jeremysart]

Thanks guys, I think maybe I can get something going here.

 

I had something strange happen when I was trying to play a game yesterday. I popped in a disk for an old game that is compatible with the PC, when I booted it said "Non system disk, or disk error." I went to switch the disk out a couple times, but one of the times I wasnt thinking and accidentally opened the hatch on the drive while it was spinning/ reading the disk. Now when it boots to IBM Basic, when I type anything, the keys come out wrong or garbed. For example, I'll type a and get Bv, or 1 and get Ghjr4 ??

I have a couple old clicky keyboards, and I tested to make sure that is was not keyboard failure. I switched them out with the computer on, and tried re-booting, I still get this strange error.

I don't know why it would do this. Is there perhaps a way to reset the BIOS or something?

[jaybird3rd]

Thanks guys, I think maybe I can get something going here.

 

I had something strange happen when I was trying to play a game yesterday. I popped in a disk for an old game that is compatible with the PC, when I booted it said "Non system disk, or disk error." I went to switch the disk out a couple times, but one of the times I wasnt thinking and accidentally opened the hatch on the drive while it was spinning/ reading the disk. Now when it boots to IBM Basic, when I type anything, the keys come out wrong or garbed. For example, I'll type a and get Bv, or 1 and get Ghjr4 ??

I have a couple old clicky keyboards, and I tested to make sure that is was not keyboard failure. I switched them out with the computer on, and tried re-booting, I still get this strange error.

I don't know why it would do this. Is there perhaps a way to reset the BIOS or something?

Have you tried powering down the machine? It's generally not a good idea to plug/unplug those old keyboards with the power on; they weren't designed to be hot-swappable.

[nathanallan]

um, Easter Egg?

 

Do the same characters come up all the time? Example, 1=Ghj4 all the time and not just random characters on the screen?

 

Document this, if it's an actual error then you'll be able to fix it as it's bound to have happened before.

 

If it isn't an error then it's bound to have been found by someone by now.

[jeremysart]

I did try powering it down, its not just reading from memory.

 

@nathan, yeah, the keys show up the same each time, but have slightly different results each time the machine is powered off and back on.

Im sure whatever it is is simple, otherwise I would image something would be corrupt and Basic would not load. Maybe it will go away when I try booting DOS.. hopefully the disk drive works properly

 

Oh, and I am definitely interested in your 360K drive! PM Sent.