[VECTREX Power Switch Revealed]

Hi, thanks to this post I decided to tackle the job myself.

 

I've made a video on YouTube that clearly explains how to service this switch for others.

 

You can see it here: https://youtu.be/VW8Rlx6f8ps

[Atari ST Floppy Drive Repaired]

My question is, could the caps in question cause the drive to not spin? Or is the drive motor just toast?

 

Possibly motor, but for a couple of quid it's worth trying the caps first IMHO.

[Upgrading 520STF C070789-001 Rev F2 to 1Mb - which components?]

Thanks, I already have the chips, really don't have any intention to use this machine beyond a few games.

[Upgrading 520STF C070789-001 Rev F2 to 1Mb - which components?]

Capacitors: 220nF / 0.22µF

Sockets, DRAM and Resistors: correct

 

Thanks. So are these just normal caps I need then, not these "Decoupling Capacitors" ?

 

Also I note the resistors are aligned alternately, I assume I carry on the same trend?

[Upgrading 520STF C070789-001 Rev F2 to 1Mb - which components?]

Hi,

 

I've bought an Atari 520STF which had a dodgy floppy drive and I've fixed replacing some caps following a thread on this forum.

 

Now I can load the many games that came with it, I notice many of them require 1Mb so it's time to upgrade. I'm not interested in going larger than that and would like to keep the machine original(ish).

 

I'm after advice on what else I need to buy as I'm really very rusty on my electronics.

I opened it up and found the attached photos.

 

Looks simple enough, digging around I decided to order 16 x 256kbit chips TMM41256AP-12 which are Toshiba DRAM of the same spec that's on the board already.

 

Rather than solder direct to the board I'm going to order these IC Sockets from Farnell which should be OK rather than soldering direct to the board for obvious reasons.

 

I understand that those brown capcitors are Decoupling Capacitors of 100nf / 0.1uF ? I've no idea what these are - any pointers?

Any idea if I also need three 68 Ohm resistors for CAS and RAS signals - R71, R72, R73 (so I've read!)

 

If someone could kindly point me to the relative component on Farnell I'd really really appreciate it, many thanks.

[Atari ST Floppy Drive Repaired]

Excellent! Just remember to install sockets, don't be soldering chips directly onto the motherboard!!! And assuming you are adding the additional 512Kb, don't forget the 3 (I think) resistors that are required.

I've just received a couple of 16Mhz 68000 CPUs that I am going to install in my STFM and STe, with switch to toggle 8/16Mhz, but I've got to unsolder the 68000 in the STFM before I start - not looking forward to that lol

Heh, way ahead of you. I was thinking to get these?

http://uk.farnell.com/te-connectivity-amp/1-390261-4/socket-ic-dil-0-3-16way/dp/1101347

 

Good luck with the processor! Sounds like a fun one.

[Atari ST Floppy Drive Repaired]

That's great news!!! It's fantastic when an old FDD can be salvaged =)

Even better when it's fixed for £1.31!

Next stop - 16 x DRAM chips onto the board.

[Atari ST Floppy Drive Repaired]

I recently bought a 520STFM, my first Atari (I've always been an Amiga guy)

Unfortunately the floppy drive would not read disks, it would go throughs the motions, spin up, head move, but just boot to TOS.

I discovered this thread through a Google search and sent the wife out to Maplns for some caps for £1.31. Swapped them both out on this Sony drive and it now works perfectly.

Thanks guys!