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Re: PCB Build - Progress - Post your Pics here :-)

Posted: Fri Sep 14, 2018 10:32 pm
by PhilC
Cool, will wire up the 12v and put the ram in tomorrow.

Hopefully this has given the rest of you some confidence to take the next steps, :D

Re: PCB Build - Progress - Post your Pics here :-)

Posted: Fri Sep 14, 2018 10:36 pm
by exxos
Forgottenmyname wrote: Fri Sep 14, 2018 10:32 pm wire up the 12v .
? Wire 12V to what ? Nothing actually uses 12V on the board other than the 12V pull up on the RGB port. (not sure if that's needed for scart switching)

Re: PCB Build - Progress - Post your Pics here :-)

Posted: Fri Sep 14, 2018 11:23 pm
by troed
exxos wrote: Fri Sep 14, 2018 10:36 pm ? Wire 12V to what ? Nothing actually uses 12V on the board other than the 12V pull up on the RGB port. (not sure if that's needed for scart switching)
The ubeswitch uses the 12V pin on the monitor out.

Re: PCB Build - Progress - Post your Pics here :-)

Posted: Sat Sep 15, 2018 12:55 pm
by frank.lukas
exxos wrote: Fri Sep 14, 2018 10:36 pm ? Wire 12V to what ? Nothing actually uses 12V on the board other than the 12V pull up on the RGB port. (not sure if that's needed for scart switching)
The +12V over a 1.2K Resistor are using for scart autoswitching.

Re: PCB Build - Progress - Post your Pics here :-)

Posted: Sat Sep 15, 2018 1:19 pm
by exxos
I wonder if 5v would work for scary...

Re: PCB Build - Progress - Post your Pics here :-)

Posted: Sat Sep 15, 2018 1:36 pm
by frank.lukas
When you have a TV with Scart try it. Connect a Atari ST/STE to your TV and with the +12V the TV switch automatic when you power the ST/STE on to the right Scart Input.

Re: PCB Build - Progress - Post your Pics here :-)

Posted: Sat Sep 15, 2018 1:56 pm
by Icky
Looking at SCART Wikipedia page if I am not mistaken Pin 8 the switch pin can have different voltages which also selects different aspect ratios.

https://en.wikipedia.org/wiki/SCART

Re: PCB Build - Progress - Post your Pics here :-)

Posted: Sat Sep 15, 2018 3:05 pm
by PhilC
I don't have access to a start tv at the moment, I'm using an NEC multisync VGA but do have a scart to HDMI adaptor, which I can use my HDMI to DVI lead I guess?

Will probably put the ram board in and then see what the current load it, if thats still OK, will likely plug my recapped PSU in and see what happens, ie 5v and 12v.

I'll report back with that later on, will get the scope out just in case.

Re: PCB Build - Progress - Post your Pics here :-)

Posted: Sat Sep 15, 2018 8:33 pm
by PhilC
Today so far.

Plugged my 4mb mmu type upgrade made by Exxos into the board with my bench power supply supplying just 5v and gnd.

Current draw is presently a stable 930ma and the only chips to even get slightly warm are the two ram chips on the mmu adaptor, maybe around 40C.

Still no display but I think that's down to the ubeswitch?

Will try the recapped power supply next.

Re: PCB Build - Progress - Post your Pics here :-)

Posted: Sat Sep 15, 2018 9:06 pm
by PhilC
So, with the psu in place, no output to either my scart to hdmi or to the ubeswitch output. Will grab the scope and see what I can find.