400 cartridge door power switch mod?

[SS]

Does anyone know of a way to add a simple mod to the 400 power door so that the system WILL NOT shut off when the cartridge door is open?  And, perhaps more importantly, is there any good reason as to why I should not do this?  In the past, I have used a small stick to prop against the open door and hold down the button but this necessitates always leaving the cartridge door open while running a game or program.  I am asking because I am thinking about getting an A8PicoCart to use with my RAM modded 400 but I would like to be able to have access to the cartridge's reset switch while the machine is running.  Thanks.  

[+Stephen]

On all of my 400/800 machines, I solder in a tiny jumper across the bottom of the power PCB which makes the switch act always closed.  This can easily be removed with zero damage to the machine.  The only problem is, it requires a full disassembly of the machine.

[+x=usr(1536)]

33 minutes ago, Stephen said:

On all of my 400/800 machines, I solder in a tiny jumper across the bottom of the power PCB which makes the switch act always closed.  This can easily be removed with zero damage to the machine.  The only problem is, it requires a full disassembly of the machine.

 

...And if you've never disassembled a 400 before, please watch a few videos before doing it.  There are some catches in disassembly that while not a huge deal in and of themselves, can result in case damage due to 40-plus-year-old plastics being involved.  As an example, it's entirely possible to end up with no way to put the keyboard back in its original location if certain small plastic tabs are damaged.

 

 

[SS]

3 hours ago, Stephen said:

On all of my 400/800 machines, I solder in a tiny jumper across the bottom of the power PCB which makes the switch act always closed.

I don't relish the idea of opening up that 400 case again!  It was quite a struggle to get it back together the last time, largely because of that wound-up RF cord.  Do you know of any diagrams that detail exactly what contacts that I should solder my jumper to?  If I *am* going to go to the bother of opening everything up again, I should probably give thought to finally putting in that "Super Color CPU Card" that I have been sitting on too.  Thanks for the insights.  

[+x=usr(1536)]

1 hour ago, SS said:

I don't relish the idea of opening up that 400 case again!  It was quite a struggle to get it back together the last time, largely because of that wound-up RF cord.  Do you know of any diagrams that detail exactly what contacts that I should solder my jumper to?  If I *am* going to go to the bother of opening everything up again, I should probably give thought to finally putting in that "Super Color CPU Card" that I have been sitting on too.  Thanks for the insights.  

 

If you open it up to install the SCCC, the RF cable can be completely removed 

 

Mine has the monitor cable running out of the back of the case where the channel selection switch is located.  Didn't even remove the switch - with the switch set towards the outside of the case, there was plenty of room to run the cable supplied with the SCCC and still reassemble everything.

[Peri Noid]

5 hours ago, SS said:

is there any good reason as to why I should not do this? 

If you know what you're doing then not. Otherwise, it may be dangerous to remove or insert a cart while a computer is on. Not in general - but sometimes. And probably that's why there was an integrated power switch to act when the door was open, in a 400 and in an 800.

[_The Doctor__]

No, the cartridge door was a safety interlock and an ease of use feature to completely start the machine from a fresh state on cartridge insertion and removal.

Machine won't power up with the case off due to safety interlock.

No RF emitted when door is open as power is off.

You can still hot plug like on an XL/XE just a little tougher to rock a cart in, some dummy carts had a switch to turn on and off cart power, and protection bypass carts etc. were all used without issue, while most folks using them had just bypassed/jumped the interlock to use them.

Edited March 18 by _The Doctor__

[scotty]

I did this as a 12 year old kid.  Just put a paper clip or something small in the latch mechanism.  takes 2 second, very simple very easy, and is not permanent.