Worklog PiiStationU Portable

[MRKane]

I don't know if my own thread is the correct place to ask this, but does anyone know what the dimensions for the PS2 barrel jack male & female are? I'm working on a power solution and are tossing up between finding a solution here, or cutting up the PS2 PSU and just dropping a new connection on the end so I can make use of things like switching barrels

 

[MRKane]

Ok so it turns out that the PS2 female power connection IS switching! That just really changed and simplified my power solution!

 

[gaetano]

I have a question, how did you do to maintain the motherboard cooled?

 

[MasterNate]

The heatsink and fan keep it cool. It just takes trial and error to see how small you can trim the heatsink and how small you can make the fan.

 

[MRKane]

I brought that fan, and to be honest had no other use for it so started cutting bits off until it fit and hoped it'd work. As fate would have it that appeared to be enough. I've done an hours burn-off and a couple hours worth of play. Blind luck I suppose.

 

[Dave Mackintosh]

I've looked into the Switch fan. They're hard to find (in the UK), expensive and about the same thickness as the blower that comes with the slims. Air movement wise in not sure how much better than stock one they are but they're not likely to be equal to stock solutions.

I'm experimenting with a couple heat pipe + blower solutions that take up very little space. Keeping my slim around the 40-43 mark which is very healthy so far.

 

[MRKane]

Small update and the inclusion of the worlds most awesome low-battery indicator light.

HELLO DAVE

Yeah, it's only a few zeners and a LED that I ground the end off of to make it fit, but it really is ominous.

Seriously though - fixing this 3D printer has chewed up a lot of my time but I'm finally printing out the bits I need to complete this project. Not sure if I'll get it done before I go to Europe however.
Interestingly if I jury rig my power setup into a simple DCDC 4A converter board, for testing the indicator light, the unit was happily running at 5.6V, but with batteries it dies at about 6V - I am open to suggestions as to what's happening here, and also if there's any way we can cheat that 6V cutoff for the unit.

 

[fibbef]

At first I thought you were talking about the home button being lit up.

HELLO DAVE

BUT THEN I SAW IT

And it’s not like I need another reason to rewatch 2001.

Pretty good choice for filling the vacancy where the tablet’s camera was. BUT this could have been the world’s first portable to incorporate the EyeToy.

 

[MRKane]

Right - heading off to Europe in about six hours but that doesn't mean the modding should stop! I've been working on the battery pack, which is using 4x18650 batteries. I wanted to make a more complete solution here so purchased some battery charging circuits. They seem to run fine off of the PS2 PSU so I can charge and play at the same time. The big catch has been that they actually seem to discharge the batteries when left. I've tried installing a switch to isolate them on two lines but there's still a tiny drain (somehow - I've no idea how that is happening).
Product: https://www.aliexpress.com/item/2S-Li-ion-18650-Lithium-Battery-Charger-Protection-Board-7-4V-Overcurrent-Overcharge-Overdischarge-Protection-4A/32754718846.html?src=google&albslr=224361831&isdl=y&aff_short_key=UneMJZVf&source={ifdyn:dyn}{ifpla:pla}{ifdbmBM&albch=DID}&src=google&albch=shopping&acnt=494-037-6276&isdl=y&albcp=913263744&albag=48828809226&slnk=&trgt=388120373908&plac=&crea=en32754718846&netw=g&device=c&mtctp=&gclid=CjwKCAjws6jVBRBZEiwAkIfZ2mfwDSU_5uB4-3QvObDzPgu7t_1JzNNwylqvJfDpFdzYe2ORuALAcBoCIDUQAvD_BwE

What I'd like to know is: What's everyones preferred method for this sort of thing? I'd be dead keen to put an order through and adjust things to suit here if it's going to make my life easier. For powering the charger I've got the PS2 PSU which has power to spare. The case is 3D printed and fits on the back of the unit - I'll grab some photos before I leave least anyone wishes to see it

EDIT: It seems that the two batteries discharge at a rate of 0.04V per day with the positive and negative terminals of both batteries disconnected, but if I disconnect the middle point terminal from the charging board they don't seem to discharge. I'll give it another night to confirm. Weird.

 

[Dave Mackintosh]

I imagine that the ICs that control logic between charge and play switching remain relatively idle but still active while powered by battery so the drain is probably an ill programmed "should I switch?" "no" "should I switch?" "no" loop.

 

[MRKane]

I figured it had to be doing something funny like that, and it turns out it's REALLY funny. This'll be my last post in a while as I'll be travelling around Europe so won't be near the workbench, but here's what I've observed:

-Charging PCB has three terminals (front, middle, end)
-Disconnecting all but the middle still drains battery, and front and end show a potential across them (WTF? How?!)
-Disconnecting only the middle seems to deactivate the entire PCB and over 12 hours there was no observable drain

I'd love it if there was one I could just leave connected, but for the better part...I think it's getting a switch because it's too cramped to fit a relay lol

 

[Stitches]

I figured it had to be doing something funny like that, and it turns out it's REALLY funny. This'll be my last post in a while as I'll be travelling around Europe so won't be near the workbench, but here's what I've observed:

-Charging PCB has three terminals (front, middle, end)
-Disconnecting all but the middle still drains battery, and front and end show a potential across them (WTF? How?!)
-Disconnecting only the middle seems to deactivate the entire PCB and over 12 hours there was no observable drain

I'd love it if there was one I could just leave connected, but for the better part...I think it's getting a switch because it's too cramped to fit a relay lol

IIRC, the cheap method of cell balancing that some of these boards use is to slowly drain the cells until they both hit an arbitrary point like 4v, then as long as the cells are close in voltage it shouldn't do it again. It's really sketch.

 

[MRKane]

So the project is now complete (photos to follow, probably in the "projects complete" section) but she's a little on the heavy side packing 4x18650 batteries. Part of this was because I thought it'd draw a current of somewhere in the territory of 5amp thanks to the specifications on the HDMI screen I purchased.

However that's not the case, but having purchased all the bits I decided to go through with it anyway. A notebook calculation from a half-hour burn-off suggests I'd get about three hours of play out of four batteries. The question I've got it: What is everyones experience on this sort of thing? Would I be better having two batteries, less weight, a minimised setup (as it's got a funny thing sticking out the back of it...but I don't know if I'll be able to fix that! lol) instead of having four batteries. Where does the personal preference lie?

 

[ohkin86]

Hello,Is it done?
can you upload some latest photos of your psu portable?

 

[MRKane]

I have been very lazy getting this up (mostly due to real life turning into a routine of working and sleeping, and finally getting the PS2 to N64 adaptor project working as I intended) and am not totally sure that I'm finished with this yet but it's kinda in the "close enough" situation. For that reason I'm not sure if it'll be going up on the "projects complete" thread as the battery pack at the back irks me.

Final interesting details:
-4x18650 batteries, with a dual internal charger setup and a couple of relays to isolate things correctly during charging (I'm wondering about going to 2x18650 batteries) while I've not managed to run the batteries down I'm estimating I'll get about 3 or more hours of playtime out of it
-HDMI screen
-No headphone out
-All WII buttons linked up to different internal functions - TV button turns screen on/off, power toggles control analogue, home button is PS2 reset/on, and the rest are as you'd expect
-I didn't use the trimming guide by GMan as when I did the internals it hadn't come out yet, but I could save a little space internally if I did decide to do so. Given that it works, and it works well, however, I don't see myself doing this
-It's actually a real pleasure to play and gets a fair bit of use while my partner is using the TV or I've got a spare moment

Here's 25,000 words per second, on a phone camera, with one hand:

P.S. Not for sale. I posted a few pictures on my Facebook and had an offer before the battery holder on the back had finished drying.

EDIT: So I'm still not happy with the battery pack, and after playing around with placeholders for the bits and pieces I was thinking of buying I came up with a better conformation for the arrangement of this. It'll be odd, but probably more space conservative. I did get the chance to measure the draw on the unit, and it's come in at 2.75A which surprised me given that the datasheet for the screen said it'd draw 3A @ 5V (thus why all the batteries).

 

[MRKane]

Ok, never one to leave well-enough alone, I'm still not happy with that battery pack. I need to "build it better" and that'll involve a better charging circuit. I've decided to go with this one, and here's the question: can this charge batteries with an 8.5V power supply or does it have to be 9V? See 8.5V would make my life much simpler, and it's going to get experimented on when it arrives but it's just nice to know

https://www.ebay.com/itm/3117219872...il&pgrp=main:email&e=op&mchn=em&s=ci&mail=sys


The other thing was always that USB stick, and for the life of me I just couldn't seem to get a USB to SD adapter which worked after I'd pulled it apart and trimmed it. So I got a bee in my bonnet and purchased a selection, and what do you know the cheapest one worked. That neatens up the running profile:

 

[Dave Mackintosh]

Love the SD card slot. Had planned that for mine too, which adapter did you go for? The only one that works for me is a cheap Chinese one that came with one of my 3d printers lol

 

[MRKane]

The adapter I found successful was a dirt-cheap on that I picked up off of a local buy and sell site - and I'd dismantled several but this one was the only one that didn't get destroyed in the process. It's actually the very one that's in my video above (I'd just got it when I made the video).

 

[uesporto]

what's the max voltage that a stock regulator of a 7xxxx series could handle?

 

[MRKane]

what's the max voltage that a stock regulator of a 7xxxx series could handle?

You know I was actually wondering that myself. From a battery angle it'd be really handy if the unit would run off of 9v without issues even, but truth be told I didn't have the opportunity to test it because my little variable transformer decided to die on me.

I'd imagine that some of the components could be inclined to give out more quickly, but I really don't know if anyone has investigated the max the unit can run off - only the minimum.