exxos's Atari, Amiga & retro forum

That's awesome! Not to mention fast!
:dualthumbup:

I changed memory on two ST ram cards for the TT. These cards have jumpers for 2/8Mb already but you can only use 2Mb. Didn't want to do just one since I know I had two boards. Finally found my other one. I had bought 8Mb SIMM modules with 16 chips on them rather cheap. Desoldered the ones on the SIMMs and on the RAM card. Old ones was 100ns and the new ones are 60ns. Used a lot of gooey flux and soldered in the new ones. Tested for two hours on each card. Tested the cards before any hot air touched them so I knew that they worked before my work commenced. I'm happy it went so well. Slight hiccup when a pad almost came off but I managed to save it. That was all really. Measured around that and the J leg next to it didn't have contact with the board so went over a few legs with soldering iron. Found the usual stuff like two or three places with solder bridges on the legs. The first card went much smoother. Strange. Removed the the two electrolytic caps on both boards and checked them. They were fine but changed them on one card since it had a little bulge on it.




I have also got my hands on a PuPla and a FRAK board for my PAK. The PuPla is already finished since I bought it like that. The FRAK however needs some love. So I have soldered in all the SMT stuff on top and bottom.

@DoG - nice upgrade of the ST-RAM board for the TT. I wasn't aware there was an SMT version as my TT was through hole RAM. That board was a bit of a different upgrade https://www.exxosforum.co.uk/forum/viewt ... f=15&t=357 but yours keeps the aesthetics of the original board.

Your mention of the caps makes me think I need to check my boards out to see if their caps need replacing or are bulging.

@DoG where did you get the frak from, just wondering if they had any more.

Icky wrote: 18 Jul 2020 08:58 @DoG - nice upgrade of the ST-RAM board for the TT. I wasn't aware there was an SMT version as my TT was through hole RAM. That board was a bit of a different upgrade https://www.exxosforum.co.uk/forum/viewt ... f=15&t=357 but yours keeps the aesthetics of the original board.

Your mention of the caps makes me think I need to check my boards out to see if their caps need replacing or are bulging.

I have one 2Mb ram board as well and it looks like yours with TH. The bulge was self-inflicted because I tried using the heat gun from the other side and the cap couldn't handle the heat... :D :shock: I don't know why I tried that. It pretty logical when you think about it. So yours are probably fine.

PhilC wrote: 18 Jul 2020 09:12 @DoG where did you get the frak from, just wondering if they had any more.

I'll PM you.

I finally found and programmed my TF534 I built over a year ago and never tried out. All seems to work fine but installing Xilinx ISE 14.7 was a pain in the butt. Even had to go into bios and set stuff up. Will hopefully try run the board later.

Did some pcb to tackle the fixes as in the 'Mandatory list". Point 3 and 4/DMA and 1772 pull ups. The DMA is often socketed from factory so that was easy to attach. I had to desolder the 7406 and put in a socket to fit my little board in between.



I swear I fixed pin 8 leg on the 7406 after the photo was taken as well as clean up the solder.

Did a little Mouse/Joy auto switcher. I tested it with two mice attached. Click on fire/left mouse button and only that unit works.

Nicely done @DoG