Lynx still giving me trouble...

[Nachoman]

Hey guys,

 

Some of you may have read my thread about my lynx not working, it started off by being a bit funny with batteries, working for a short period on an old set of batteries, then slowly having to turn up the brightness to continue play and eventually got too washed out to see and the sound died.

Originally I thought it was just dead batteries but when I switched for a new set, it didn't boot at all, just backlight but it would not adjust with the dial. when I switched back to the old batteries, I got full fine gameplay again, but then fizzled out as before. If I used a combination of batteries, new and old, it would work for longer but with a brighter screen than it should on the lowest brightness but after a time, would do the same as before and fizzle out over a period of 5-10 minutes. Now I cant even seem to get it to boot up now matter what battery combination I try.

 

So... I got advised to do a cap kit, which I have just done, but has made no difference sadly. Can anyone suggest anything to help? I have a diode and MOSFET coming through the post from Cowdog (thanks for that), but now im abit concerned its something more sinister.

 

I don't want to spend more time and money changing parts if its something more terminal like screen or processor, if that's the case I would probably just get another and swap my case over but id rather keep my original board.

 

Thanks in advance for any help

[+af0l]

Is that a mkI or mkII? Anyway, you could feed 5V from a phone charger or similar to the 5V rail and see if the downstep converter (mosfet and zener) is at fault. I have mine working like that. I'm no expert, but if it's working with new bateries and it does not with with new ones, I'd be very careful with 9V inputs. The killer in Lynx is the common rail for 9V and 5V. When downstep fails it can go both ways. You can get something like 2.3V instead of 5V, which won't work, but it won't kill anytning either. The alternative is lethal 9V all around. The chips do not like that...

 

So, feeding 5V to the proper spot (C41 in my case), might give you an idea if there is hope...

 

More here:

http://atariage.com/forums/topic/259440-lynx-kaput-after-recap/?do=findComment&comment=3641084

Edited December 9, 2016 by af0l

[Nachoman]

Thanks for the reply.

 

I think what you have suggest has happened, I had another look at the lynx earlier and noticed when I power it up within seconds Suzy goes red hot, so I guess that's that fried now!?

 

I'm new to the Lynx and wasn't aware they could basically kill themselves like this, normally they have sacrificial components that prevent frying main internals, so I guess its my fault for keeping turning it on trying to isolate the problem.

 

I guess this is what the 5v mod I have read is about.

[+af0l]

Thanks for the reply.

 

I think what you have suggest has happened, I had another look at the lynx earlier and noticed when I power it up within seconds Suzy goes red hot, so I guess that's that fried now!?

 

I'm new to the Lynx and wasn't aware they could basically kill themselves like this, normally they have sacrificial components that prevent frying main internals, so I guess its my fault for keeping turning it on trying to isolate the problem.

 

I guess this is what the 5v mod I have read is about.

 

Well it's bad design, not your fault. The step down, while efficient, it's very dangerous in case anything goes amiss. Hot chips are not a good sign. You might try 5v directly, minding the voltage (doesn't hurt at least). Maybe you're in luck...

 

[cowdog360]

Yeah, but if your Mikey or Suzy is red hot, then they are most likely damaged.. and there is a possibility that other chips are as well. I have done a MIkey/Suzy transplant with success in the past.

[Nachoman]

well...seems after all it was the Zenner Diode, replaced that (thanks Cowdog360) and it worked perfectly. Amazing really, I would have put money on something being fried after Mikey was red hot.

[cowdog360]

So yet another example of: If you have a Lynx II, don't wait any longer. Replace the Zener and MOSFET, as they are the core of the power supply. If you don't you may get lucky like Nachoman.. sometimes you won't. No reason to take a chance when the parts are less than $2 total!