Meanwell PT-65B

September 17, 2009

The new PSU has turned up. Need to look at getting connectors sorted out….

New Power connectors (KK series in the 3.96mm pitch) have now turned up from RS, just waiting on the Crimps (now here).

  • 6 way locking housing stock no. 173-3105
  • 3 way locking housing stock no. 173-3076
  • Crimp terminals – 22-28 Awg Stock no. 245-4718

More? GS Replacement PSU

September 16, 2009

As you can tell I have just started “blogging” today. The main reason i put this together was to have a place people might be able to get information on projects I am working on and if it helps them then it was worth it. It also gives me a record and something more to do that is Apple IIGS related yippie 🙂

My latest project is to replace the insides of ageing GS PSUs with a modern equivalent. Why you might ask? Well it all goes back to having things original. My main GS happily works with a Mini ATX and external power pack. Its great as all the heat generated by the PSU is not internal to the GS. This is perfect for day to day use…well once a week use :P.

I have a couple of older GS machines (and also my newly acquired ROM03…but it has a 110v psu another reason for this project) that have PSUs that struggle when under i wanted to use them as my guinea pig.

After some posting on the comp.sys.apple2 i was pointed into the direction of a Meanwell PT-65B open frame switching PSU (It has been used to replace a Vulcan PSU with some minor modification to component placement). Though this should fit inside an existing PSU casing it only outputs +5/+12/-12 the -5 is missing and you need to use a negative regulator to produce a -5 for the GS.

The GS connector has :-

  • Pin 7 -5 Volts 0.25 Amps
  • Pin 6 -12 Volts 0.25 Amps
  • Pin 5 +12 Volts 1.0 Amps
  • Pin 4 +5 Volts 4.0 Amps
  • Pin 3 Not Used
  • Pin 2 GND
  • Pin 1 GND

I am hoping to have this completed over the next month or so but suspect there will be some challanges around actual placement and fixing inside the old PSU case etc and also that i will need help from friends who are more clued up around electronics as well as the Apple II community 🙂

Today I ordered my PT-65B and also picked up the following from Maplins

  • Negative L7905CV Regulator to provide -5V from -12v
  • Radial-lead style tantalum Capacitor 35v 2.2uF to be used with the Regulator
  • TO220 Insulator and Bush so i can isolate the Regulator from the PSU case which i will attach it too.


September 16, 2009

One thing i fondly remember was opening my GS (ROM01 model in coloured packaging) in late 1989 and the excitement of getting my first computer. Over the years i have collected a number of used GSs all of various ages, models and shades of yellow. I have a couple which are not too badly discoloured, but i really liked the original platinum colour of the GS and have wanted to get one in original colour.

A boxed unused ROM03 GS was listed on ebay recently and i was lucky enought to win it :). I was actually surprised i won it as its the first one i have seen on ebay since i have started looking and was expecting it to go for lots more. The box isn’t great (though its complete and still sturdy) and inside its missing the mouse (shame) and one of the system disks, but apart from that the manuals are sealed with a Tour disk, and System tools disk as well as new keyboard and ADB cable all bagged up.

The GS is as new and there is not a mark on it, with totally original colour and shiny and new inside as well as outside. It was like christmas :-). I did power it up and all self tests worked.:-)

New Transwarp GS

September 16, 2009

Over the years i have replaced bits in my main GS (yes i have many lol) to bring it up to date…well as best you can a 20+ year old computer. I have replaced the PSU with modern mini ATX (using LittlePower GS) and used CFFA cards to use a CF as an HDD. I still enjoy the feeling of something original and one item i have been looking for over the last 15 years is a boxed Transwarp GS card (as well as a new GS in a box…more of that in a bit)

I was lucky enough recently to get the opportunity to buy a brand new unopened one :). It wasn’t cheap and I have yet to open it as I have also acquired a used Transwarp GS card which i am currently using. I don’t plan to keep it sealed and will be opening it shortly once other retro projects get completed.

First Post…

September 16, 2009

I didn’t have a IIGS for very long when i was younger, and sold it around 1992 and used the money to buy my first PC. Since about late 90’s have been collecting IIGS computers and tinkering with them ever since. Nothing major i am not a electronics engineer or programmer just a user :). I have enjoyed building up the system i used to have and collecting the rarer items as they come available. I am fascinated by the machine, probably because it was an underdog at the time and the end of the Apple II line, whatever the reason its a great retro hobby to have :).

After many years of being a PC person (in fact my work is all Windows lol) I am now an owner of a modern MacBook Pro….only taken me 20years+ to forgive Apple for killing of the Apple II 😉