2 Dead Lynx II: any ideas?

[galax]

I picked up my first Lynx and about 30 games at the weekend. It's a Lynx II in great condition, and with it came two other brand new and boxed but non-working Lynx IIs. They were dead on arrival when they were new, so even if I can't get them working they might be useful for spare parts.

 

Dead Lynx A completely unresponsive: I tried with both fresh batteries and a Lynx PSU and there is no response when I press the 'on' button. I tried connecting the negative battery terminal to the negative (ground?) pin of the speaker jack (which I saw in a YouTube video) - when I did this the screen backlight comes on but there is still no response.

 

Problem Lynx B works perfectly except for the screen display being fixed solid black. The backlight switches on and off, sound plays, buttons respond etc., but the 'brightness' setting does nothing. Again I tried both batteries and a PSU.

 

I tried switching over the motherboards of these two machines, to see if Lynx B's problem is just with its screen, but there was still just a solid black image. I was wondering if I could swap a McWill screen into this machine, but I'm not sure if this problem would persist with that screen too- is there any way I can test whether that would work?

 

Is there any other A/B testing I can do between these two machines to help identify the problem components? Are there any other standard things I can test for? Thanks in advance!

[McWill]

I picked up my first Lynx and about 30 games at the weekend. It's a Lynx II in great condition, and with it came two other brand new and boxed but non-working Lynx IIs. They were dead on arrival when they were new, so even if I can't get them working they might be useful for spare parts.

 

Dead Lynx A completely unresponsive: I tried with both fresh batteries and a Lynx PSU and there is no response when I press the 'on' button. I tried connecting the negative battery terminal to the negative (ground?) pin of the speaker jack (which I saw in a YouTube video) - when I did this the screen backlight comes on but there is still no response.

 

Problem Lynx B works perfectly except for the screen display being fixed solid black. The backlight switches on and off, sound plays, buttons respond etc., but the 'brightness' setting does nothing. Again I tried both batteries and a PSU.

 

I tried switching over the motherboards of these two machines, to see if Lynx B's problem is just with its screen, but there was still just a solid black image. I was wondering if I could swap a McWill screen into this machine, but I'm not sure if this problem would persist with that screen too- is there any way I can test whether that would work?

 

Is there any other A/B testing I can do between these two machines to help identify the problem components? Are there any other standard things I can test for? Thanks in advance!

First you should test the voltage on each LYNX with original PSU. The power +5Volt should be about 4.9 Volt. If it is much more (7 Volt or more) the 2 ASICs definitely are defective. I guess the problem on LYNX B will be solved with my LCD replacement. But also the SUZY IC could be defective.