VOGONS


First post, by renejr902

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Hi! I need help with my first Tandy pc ever. A Tandy 1000RLX/A with no hard drive. ( not the B version i'm lucky ) But when i turn i on, the tandy makes a BIG NOISE loud and very annoying, its hard to explain and its never stop until i turn it off. My vga crt monitor dont do anything, screen stay black, the vga crt dont seem to be recognize by the tandy. I have a xt-ide isa card for using it with the tandy. But for now i have to understand the problem. Thanks for help

Edit: The big noise come from the speaker.

The chip in the picture become VERY HOT, i even get a little burned on my finger. Other component and chips aren't hot.

Last edited by renejr902 on 2025-08-24, 22:51. Edited 1 time in total.

Reply 1 of 29, by rmay635703

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I would remove everything (isa card, hard drive)

So you just have a floppy and try to boot with no keyboard or anything else plugged in.

On my RLX-B the system goes bananas like a bad keyboard controller after I installed a hard drive but usually posts and boots.

If it won’t I had to try to force clear the cmos which I no longer remember how to do in my case it appears I need a new battery and the PSU is a bit weak

Reply 2 of 29, by renejr902

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rmay635703 wrote on 2025-08-24, 22:44:
I would remove everything (isa card, hard drive) […]
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I would remove everything (isa card, hard drive)

So you just have a floppy and try to boot with no keyboard or anything else plugged in.

On my RLX-B the system goes bananas like a bad keyboard controller after I installed a hard drive but usually posts and boots.

If it won’t I had to try to force clear the cmos which I no longer remember how to do in my case it appears I need a new battery and the PSU is a bit weak

thanks i will try your tips. i just edited my topic read the update thanks

Reply 3 of 29, by Shponglefan

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Looks like there is some corrosion on the board. Corrosion could result in things like broken traces or other issues that can lead to all sorts of adverse affects.

I would recommend removing any chips and other components before giving the board a good cleaning and inspection. If you have a multimeter you can check traces for continuity.

Pentium 4 Multi-OS Build
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Reply 4 of 29, by renejr902

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Shponglefan wrote on 2025-08-24, 23:06:

Looks like there is some corrosion on the board. Corrosion could result in things like broken traces or other issues that can lead to all sorts of adverse affects.

I would recommend removing any chips and other components before giving the board a good cleaning and inspection. If you have a multimeter you can check traces for continuity.

ok i will do it. Thanks.
i'm a little in fear... i hope the Tandy corp chip is not burned. it was so hot..

Reply 5 of 29, by keenerb

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renejr902 wrote on 2025-08-24, 22:35:

Hi! I need help with my first Tandy pc ever. A Tandy 1000RLX/A with no hard drive. ( not the B version i'm lucky ) But when i turn i on, the tandy makes a BIG NOISE loud and very annoying, its hard to explain and its never stop until i turn it off. My vga crt monitor dont do anything, screen stay black, the vga crt dont seem to be recognize by the tandy. I have a xt-ide isa card for using it with the tandy. But for now i have to understand the problem. Thanks for help

Edit: The big noise come from the speaker.

The chip in the picture become VERY HOT, i even get a little burned on my finger. Other component and chips aren't hot.

The good news is that's just a VGA bios chip, a 27C400 EPROM that should be really easy to replace. I would CAREFULLY remove that chip and check it for internal shorts, and CAREFULLY check the voltage being supplied to the socket.

https://www.alldatasheet.com/html-pdf/285715/ … 2/AM27C400.html

All you need for this is a basic low end multimeter.

On the SOCKET, with or without the chip installed, put the multimeter to an appropriate DC voltage settings. Then you would touch the red lead from the multimeter to pin 21 and touch the black lead to any exposed metal on the inside of the case, which should be grounded. The eprom uses 5v voltage; if you read anything higher than that you have a voltage problem.

On the CHIP after it's removed from motherboard, you would want to check continuity from VCC (pin 21) and the two VSS pins (pins 11, and then 31).

Reply 6 of 29, by keenerb

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Oh I see your problem. That chip is installed backwards. The little dot on the corner indicates the chip has been rotated 180 degrees from this picture I found on the internet:

http://www.oldskool.org/guides/tvdog/images/R … mBoardLarge.jpg

Which would mean you're supplying 5v somewhere it should NOT be going. That is almost certainly fatal for the chip itself, but the rest of the system might be perfectly fine!

In what part of the world do you live? Perhaps someonen could burn you a new eprom and send it, should only be a few dollars.

The loud noise coming from speaker is the random noise from the Tandy sound chip, which is actually a good thing because that means the big integrated tandy chip is likely to be unharmed.

Reply 7 of 29, by renejr902

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keenerb wrote on 2025-08-25, 00:07:
Oh I see your problem. That chip is installed backwards. The little dot on the corner indicates the chip has been rotated 180 […]
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Oh I see your problem. That chip is installed backwards. The little dot on the corner indicates the chip has been rotated 180 degrees from this picture I found on the internet:

http://www.oldskool.org/guides/tvdog/images/R … mBoardLarge.jpg

Which would mean you're supplying 5v somewhere it should NOT be going. That is almost certainly fatal for the chip itself, but the rest of the system might be perfectly fine!

In what part of the world do you live? Perhaps someonen could burn you a new eprom and send it, should only be a few dollars.

The loud noise coming from speaker is the random noise from the Tandy sound chip, which is actually a good thing because that means the big integrated tandy chip is likely to be unharmed.

all.voltage and continuity were good. we just put the chip in the good direction. i will let yoi know if its working or i will ask for a eeprom already flashed.
i live in canada

Reply 8 of 29, by renejr902

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it works thanks a lot. but the screen is in black and white.

Reply 9 of 29, by keenerb

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I honestly cannot believe it still worked, but that's tremendous news. I suspect that chip has some damage even if it does boot now!

Reply 10 of 29, by renejr902

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It works in color the lcd screen of my father sucks. Long live to crt 😃

I said the same thing toy father i hope the chip dont have somedamage. He thinks not, we will see.

The tandy ask for files for the tandy desktop os, can you tell me where i can get them ?

I will try my xt-ide isa card soon 😃

Thanks for your previous help, it was so much appreciated. I will make several test. If i doubt the vga bios chip i will try to ask for one on vogons. I think i can wait for now. right ?

😃

Reply 11 of 29, by keenerb

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renejr902 wrote on 2025-08-25, 01:17:
It works in color the lcd screen of my father sucks. Long live to crt 😃 […]
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It works in color the lcd screen of my father sucks. Long live to crt 😃

I said the same thing toy father i hope the chip dont have somedamage. He thinks not, we will see.

The tandy ask for files for the tandy desktop os, can you tell me where i can get them ?

I will try my xt-ide isa card soon 😃

Thanks for your previous help, it was so much appreciated. I will make several test. If i doubt the vga bios chip i will try to ask for one on vogons. I think i can wait for now. right ?

😃

Yeah if it's color and no corruption on crt I think it's ok, you were very very lucky.

I am not sure about the tandy files, it's been a long time since I played with my RLX. Do you have a way to put data onto a floppy disk?

I would recommend a PicoMEM over an xt-ide device; it's much more useful and can emulate floppy disks, hard disks, Adlib sound card, and even a usb mouse

Reply 13 of 29, by renejr902

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i have a xt-ide. maybe i will buy a picomem .
yes i can put anything on my 1.44 disks. i have a lot od retro pc. The keyboard show random letter or character, see the last picture, i use a ps/2 keyboard. do i need a special keyboard from Tandy ? Thanks for answer again ( i have several ps/2 and at and xt keyboard but its 5 pins din )

Reply 14 of 29, by keenerb

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RLX is an XT keyboard, the only one I know of that had a PS/2 adapter is the Tandy Enhanced 101 key keyboard, so you'll need a big to small keyboard adapter.

Actually I don't know, maybe the RLX is AT. I can't remember.

Reply 15 of 29, by renejr902

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i tried 3 at and it doesnt work. i will try a xt with the big to small adapter and let you know in 5 mimutes 😉

Reply 16 of 29, by renejr902

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keenerb wrote on 2025-08-25, 01:42:

RLX is an XT keyboard, the only one I know of that had a PS/2 adapter is the Tandy Enhanced 101 key keyboard, so you'll need a big to small keyboard adapter.

Actually I don't know, maybe the RLX is AT. I can't remember.

i can't live without you keenerb 😄, the xt keyboard with the big to small adapter works

Thanks SO MUCH for your help ! it really appreciated a lot 😃

Reply 17 of 29, by renejr902

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another picture of the tandy desktop version

Reply 18 of 29, by renejr902

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keen 6

Reply 19 of 29, by keenerb

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Tandys are the best "old" systems in my opinion. I'm glad that one came back to life!