28 replies to this topic

[Redcurrie]

Okay, I got a TI99 and all of the requisite connections and it appears that the system has some sort of a problem. To describe it in simple terms, the output appears "garbled". I can tell to a certain extent what it should look like on my TV but there are characters where there should be letters, etc. Does anyone know what could be wrong and better yet, how to fix it?

Thanks,
Laura

[Dan Iacovelli]

Redcurrie said:

Okay, I got a TI99 and all of the requisite connections and it appears that the system has some sort of a problem.  To describe it in simple terms, the output appears "garbled".  I can tell to a certain extent what it should look like on my TV but there are characters where there should be letters, etc.  Does anyone know what could be wrong and better yet, how to fix it?  

Thanks,
Laura

just a guess: is your tv tuned to the right channel (I believe ch 3 or 4 is the correct channel)
also make sure the connections are in tight some times if they are lose they can mess up your video.
Dan Iacovelli

[Redcurrie]

Dan Iacovelli said:

just a guess: is your tv tuned to the right channel (I believe ch 3 or 4 is the correct channel)
also make sure the connections are in tight some times if they are lose they can mess up your video.

The TV is definitely on the right channel and I don't think that it is a loose connection because I have gotten the same result with two different TV-connection cables. The first one was one that I made myself and I thought that was the problem but the second was a genuine TI cable that I bought from CPUWIZ so I feel that I've ruled out the connection as a problem. There is the possibility that there is a loose connection on the inside and opening the thing up will be the next step....

Thanks for the suggestions!

Laura

[Christophero Sly]

Are you getting "garbled" output on the initial splash screen? Do you get "garbled" output with and without a cartridge inserted? Are you able to load a game, and, if so, what does it look like on screen?

[Redcurrie]

Christophero Sly said:

Are you getting "garbled" output on the initial splash screen?  Do you get "garbled" output with and without a cartridge inserted?  Are you able to load a game, and, if so, what does it look like on screen?

Yes, it's garbled on the initial splash screen. I can tell that there are colored bars at the top and bottom and a TI logo and some words (including Texas Instruments) but it's a mess. When I put a cart in, I could see a jumbled version of the cart name so I know that it can read the cart. I couldn't read the screen to see what I needed to do to start the game but tonight, I'll grab a manual and see what key to hit along with trying it to see what happens. When the splash screen was up and I hit enter, it did go to another garbled screen so it seems to work but the video output is just pooch-screwed. Ugh!!!

Thanks!

[Christophero Sly]

The initial splash screen is bypassed by pressing any key. If a cart is inserted, the next screen will be the program selection screen. On the program selection screen, Pressing "1" will drop you into TI Basic, pressing "2" should load whatever program is on the cartridge.

Regardless of the "garbled" output, is the monitor signal strong and clear?

[Redcurrie]

Christophero Sly said:

Regardless of the "garbled" output, is the monitor signal strong and clear?

It appears strong but I don't know about clear. (In my mind, garbled but clear would be like what you get if you put an Intellivoive cartridge in the INTV not using the voice unit. The picture is clear but instead of the text reading something like "Mattel electronics presents...., it reads $%&*# ^%@#$@#.) That's not what I get at all. Even the part of the screen that appears as if it should be solid green has a variety of colors. Granted that they do appear to be in somewhat of a pattern but it is a mess. If I didn't have a general idea of what the TI logo looked like and that it said Texas Instruments, it would be a stretch to decipher it. I hope that answers your question.....

[SteveW]

Actually, the cartridge port might be worn out. That's a common thing amongst used TI units. Clean the cartridge and cart slot. And put the cartridge in gently. If it's garbled, wiggle the cart around to try to get a better connection.

I've had three or four TIs and they all have worn out cart slots, some more than others. Just another quirk of the TI.

[Redcurrie]

SteveW said:

Actually, the cartridge port might be worn out. That's a common thing amongst used TI units. Clean the cartridge and cart slot. And put the cartridge in gently. If it's garbled, wiggle the cart around to try to get a better connection.

I've had three or four TIs and they all have worn out cart slots, some more than others. Just another quirk of the TI.

It also does the same thing with the intro screen that comes up when you cut it on with no cart in. Would a worn out cart slot cause that as well?

[Christophero Sly]

I mean clear in the sense of the signal producing no static, etc. I was just trying to distinguish between a problem related to the monitor cable and a problem somewhere else. If you're getting a clear, albeit garbled, signal, then the problem is likely something else.

Perhaps the PSU is faulty. Does the PSU you are using have an extention section on the input cord that includes an in-line fuse?

Also, you might try giving the cart and expansion slots a thorough cleaning.

[SteveW]

Quote

It also does the same thing with the intro screen that comes up when you cut it on with no cart in. Would a worn out cart slot cause that as well?

Probably not. It usually screws up for me with a cartridge, especially a cartridge with dirty contacts. If it's not because of the cartridge, then you really have a screwed up machine. Sorry, i'm stumped.

[Redcurrie]

Christophero Sly said:

I mean clear in the sense of the signal producing no static, etc.  I was just trying to distinguish between a problem related to the monitor cable and a problem somewhere else.  If you're getting a clear, albeit garbled, signal, then the problem is likely something else.  

Perhaps the PSU is faulty.  Does the PSU you are using have an extention section on the input cord that includes an in-line fuse?  

Also, you might try giving the cart and expansion slots a thorough cleaning.

I feel like I've ruled out the cable because I got the same thing with both a homemade one and a genuine TI one.

It may be the PSU. The one I have is the one with the extension that I guess contains a fuse. How could I check if that was the problem? Am I correct in assuming that you're saying that it may be due to insufficient, oversufficient or inconsistent power?

Laura

[Christophero Sly]

Redcurrie said:

I feel like I've ruled out the cable because I got the same thing with both a homemade one and a genuine TI one.

It may be the PSU.  The one I have is the one with the extension that I guess contains a fuse.  How could I check if that was the problem?  Am I correct in assuming that you're saying that it may be due to insufficient, oversufficient or inconsistent power?

Laura

I don't think it's the monitor cable either.

Yes, inconsistent power is what I am implying, but it's only a guess. The fact that you're getting any power at all rules out a blown fuse (I think). The PSU "brick" may be bad, but the problem may just as likely be something inside the console. If you had access to another PSU, I would try that as a next step, similar to what you did with the two monitor cables. Beyond that, I'm sorry, I am stumped.

Here is the link for the 99er message board. It might be worthwhile to ask for help there.

[Redcurrie]

Thanks for all of the help! I think my chances of running across another PS are pretty slim...is there anyone in the Houston area who would loan me one for a day or two? Also, I do have a voltmeter so if there's a way to test the PS, let me know and I'll give it a shot. Hell, what's the worst that can happen....I could electrocute and kill myself?

Laura

[Toucan]

You know, I got a TI-99/4A with a Colecovision Power Supply once that I could have swore worked. I don't remember the details, but I do remember getting a TI and looking at the power supply (since it seemed bigger) on it was "Coleco" and it worked when plugged in I thought. But to save you the trouble (and potential of creating a lot of smoke), I've got some TI's here that I can ship to you if you need a new one, with power supply. It sounds like the console itself is where the problem lies, as I have had ones do this to me before. If interested in getting one from me, just send an e-mail to toucan1@home.se , unless you want to try your luck at the thrifts.

On a follow up to this, I found a few other posts from rec.games.video.classic that talked about Coleco Power Supplies on TI-99/4A's, I guess it wouldn't hurt to try plugging a Coleco one in the TI and seeing if it works.

Toucan

[Christophero Sly]

Toucan said:

I found a few other posts from rec.games.video.classic that talked about Coleco Power Supplies on TI-99/4A's, I guess it wouldn't hurt to try plugging a Coleco one in the TI and seeing if it works.

I was going to try this once, only in reverse, but I never collected the nerve...

[SteveW]

I'm in Dallas, so if you really, really want to drive for 3 hours just to pick up a power supply, let me know. I'll even throw in some duplicate carts.

[Redcurrie]

SteveW said:

I'm in Dallas, so if you really, really want to drive for 3 hours just to pick up a power supply, let me know. I'll even throw in some duplicate carts.

Ooohh, road trip! If it wasn't so cold, I'd break out my motorcycle and make it there in an hour and a half or so. Have you scoped out any good thrift stores or flea markets around there because that may be all the excuse that I'd need!

[Xot]

It could be static electricity. I remember having this symptom all the time when I played the TI on a carpet. I started putting the console on the box when I played and didn't have any problems after that.

[Redcurrie]

Xot said:

It could be static electricity. I remember having this symptom all the time when I played the TI on a carpet. I started putting the console on the box when I played and didn't have any problems after that.

It has been sitting on the floor every time and from the amount of times that I've shocked my cat in the last week, I know the static is bad. I'll try putting it up on something when I get home!

[SteveW]

Quote

Have you scoped out any good thrift stores or flea markets around there because that may be all the excuse that I'd need!

I haven't found anything good in thrift stores here. I found a few Atari 2600 joysticks, that's about it. I'm not as much of a thrift store hound as some people around here, though. I've only been checking those stores out for a few months. There might be better thrifts around here, i've only been in about 7 or 8.

I have a box of random TI stuff, a bunch of books, cartridges (nearly all educational and home economics), and even some cassette cables I could give you. I might even have a spare Peripheral Expansion Box with a disk drive in it. One question: do you have Cherry RC Cola available in Houston? I'm dying to get a couple of cases of it. (i'm a serious soda junkie.) I'll trade you for some good sodas!

[Redcurrie]

Redcurrie said:

Xot said:

It could be static electricity. I remember having this symptom all the time when I played the TI on a carpet. I started putting the console on the box when I played and didn't have any problems after that.

It has been sitting on the floor every time and from the amount of times that I've shocked my cat in the last week, I know the static is bad. I'll try putting it up on something when I get home!

No luck, same problem....

[Cassidy Nolen]

Static solution:

Mix some fabric softener and water in a little sprayer bottle. Lightly spray the carpets on the more traveled areas, and you are good to go. In my basement, static is NOT an option

HTH,
Cassidy

As for the TI, I have very little experience, but:

If the game and system 'play', it could be a video RAM that is bad. Arcade boards will suffer from this and you can still 'play' the game, even though your ship is just a blob. Most of the time on PCB's the video RAM is socketed. I would guess 4116's by the age of the system, probably two or 4.

[Redcurrie]

SteveW said:

 One question: do you have Cherry RC Cola available in Houston? I'm dying to get a couple of cases of it. (i'm a serious soda junkie.) I'll trade you for some good sodas!

I know that I have gotten it before in 20 oz bottles at gas stations so I would say that it is available in this area. I'll start scoping grocery stores and will see what I can find!

[Redcurrie]

Cassidy Nolen said:

If the game and system 'play', it could be a video RAM that is bad.  Arcade boards will suffer from this  and you can still 'play' the game, even though your ship is just a blob.  Most of the time on PCB's the video RAM is socketed.  I would guess 4116's by the age of the system, probably two or 4.

The game and system do 'play'. I loaded Super Demon Attack last night and you can make out your ship and the planet on the lower right-hand side of the screen. The problem is that there's this 'pattern' of colors that cover the entire screen obscuring everything. I'll open it up and if it does have socketed chips, where would I acquire replacements?