Jump to content
blakespot

So, my new F18a seems to have died

Recommended Posts

I spent much of the weekend opening my 99/4A, removing the cassette jack, installing F18a, placing VGA out in the place of the cassette jack, etc.

 

Powered on and all was good. Fun last night and was online (telnet BBS) via WiFi232 and TIMXT this morning. Left the term prog loaded all day while I cleaned and rearranged the room so I can actually sit in front of the 99 to BBS properly, aaaand.... I noticed the text on TIMXT was no longer white but a muddy color. No keyboard response. I powered off and on -- no more video output.

 

I can hear the TV power up, I hit 2 for FR99, can hear things as I navigate thru it and load a random cart and I see from its LED that it's loading a cart. But no video out.

 

I tried it on a different VGA LCD, no video there either -- so it's not my screen.

 

SO disappointing. Was so looking forward to BBSing in ANSI color on the TI here on my 45th birthday (today). Definite birthday downer. I really don't want to pull everything out again and open up the TI -- no energy for that again, not tonite.

 

Any ideas out there? Is there a chance things are not fried? I now the TI needs the gfx chip to access memory, or I believe it does. So, it can't be fully fried.

 

The ribbon cable is well secured, screwed into the case. No stress on it since I turned on this morning.

 

https://twitter.com/blakespot/status/866030731725819904

 

 

Thanks.

 

 

 

bp

Share this post


Link to post
Share on other sites

I can hear the TV power up, I hit 2 for FR99, can hear things as I navigate thru it and load a random cart and I see from its LED that it's loading a cart. But no video out.

Have you tried a different monitor? One of my old 4:3 monitors failed recently, so maybe it's worth checking if you haven't already done so.

Share this post


Link to post
Share on other sites

Have you tried a different monitor? One of my old 4:3 monitors failed recently, so maybe it's worth checking if you haven't already done so.

 

Yep. Not the monitor. Does the F18a run hot? Thermal failure likely?

Share this post


Link to post
Share on other sites

If I leave the machine on, every now and again the LCD power light goes amber to green and I get message :

 

"1 analog signal -- cannot display this video mode"

 

So it's periodically sending something not VGA-coherent.

Share this post


Link to post
Share on other sites

If I leave the machine on, every now and again the LCD power light goes amber to green and I get message :

 

"1 analog signal -- cannot display this video mode"

 

So it's periodically sending something not VGA-coherent.

Last easy fix check....Is it the same cable or are you changing vga cables when you changed monitors? I've had vga cables go bad, usually the connectors on old highly used cables.

 

Worth a check, swap it out if you haven't already.

Share this post


Link to post
Share on other sites

 

Yep. Not the monitor. Does the F18a run hot? Thermal failure likely?

I have left mine on for days at times without any problems. I couldn't tell you if it runs hot or cool, though. With luck, when you do open the TI, you'll find something simple like a loose cable or connector.

Share this post


Link to post
Share on other sites

Opened the unit. Bare board, it works. Tho shield has not cut into ribbon insulation at all. Not sure what's going on.

Share this post


Link to post
Share on other sites

A few thoughts as I read through the thread:

 

1. No, the F18A does not run hot. It actually runs much cooler and uses less power than the original 9918A. Just make sure you remove the 9918A heat-sink from the upper metal shield! The original heat sink is not required and *will* cause problems and/or damage to your F18A if you leave it attached and reinstall the upper shield.

 

2. I'm not sure what could have caused the video to just "go out". I would have suspected maybe the F18A came lose in the socket and just needed to be re-seated, but you mentioned being able to hear things happening with the computer. Since the F18A provides the 16K of VRAM, if it was not seated correctly in the socket then I would expect the system would have problems accessing the VRAM, and thus most software would crash very quickly.

 

3. There is an LED on the F18A. If the LED is on then you know the F18A is powered and configured properly. If the LED is on but you do not have video, then the problem is going to be: a.) some pins on the VGA header may be shorted, b.) something is wrong with the VGA pigtail, c.) something is wrong with the external VGA cable, d.) something is wrong with the monitor.

 

4. I have seen the pigtail have a bad crimp on the IDC connector side (the end that plugs into the F18A). Wiggling the cable sometimes exposes the bad connection. If that is the problem, I will replace the pigtail, or you can re-crimp it yourself if you are comfortable doing that kind of thing.

 

You said it seems to be working with the "bare board". I think that means your F18A is working with the computer taken apart? If that is the case then you might try reassembly in steps, checking that it still works after each step. If you are putting the shields be on the motherboard, make sure they are lined up and properly secured. It is very easy to get them misaligned which can cause shorts. If you cut holes in the shield for the pigtail then I recommend putting electrical tape around the edges of the hole to protect the pigtail from the sharp edges.

 

I hope some of this helps.

  • Like 2

Share this post


Link to post
Share on other sites

 

Just make sure you remove the 9918A heat-sink from the upper metal shield! The original heat sink is not required and *will* cause problems and/or damage to your F18A if you leave it attached and reinstall the upper shield.

I almost made this mistake when I put mine together. I wanted to get up and running and almost goofed in the process.

Share this post


Link to post
Share on other sites

A bit off topic but when are the F18A's gonna be back in stock? I've been itching to get one for my Ti.

  • Like 1

Share this post


Link to post
Share on other sites

Send me a message (the "contact" form on my website (http://codehackcreate.com/contact-us) is a good way to do that) with your name and email and I will put you on the contact list. Making another batch of boards is driven by demand (I just ran out of boards last week.)

Will do thanks

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...