The Newbrain Forum

brain7 · 15-08-2017 10:09:42

Hello Newbrain specialists

Can anyone in here help me get my recently acqured Newbrain working?

Recently I acquired a Newbrain AD computer, and my plan was to get it in operation. However I am uncertain if the computer is original, or if it was rebuilt for some special purpose. Please see the attached pictures. It looks like the circuits next to the CPU 406 407 and 408 are different from normal. Also it had the small board in the last picture attached at 406 position. Do you have any experience whit this?

The machine does not boot. The CPU starts, and address and data lines are alive, but it runs inti a deadlock, and only on occasion I get garbage on the monitor.
The display is dead, but if I get lucky with the basic interpreter to load, and cursor in the monitor, I will try to fix this as well

Any help is much appreciated

Best regards brain7

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Last edited by brain7 (15-08-2017 10:13:09)

brain7 · 17-08-2017 00:31:37

Update

I got some assistance from Thomas Gutmeier at 8bit-homecomputermuseum. It seems like i have a 128K vesion of the newbrain. So this is for sure the reason for the ekstra PCB taking care of the page swaping in order to adress the larger RAM. The "Storeboard" with the RAM Circuits are ugraded with larger memory, and a quite some rebuilding took place all over the mainboard.

The great mistake i made was to remove the addittional board without noting Down the connections. Now i have no way back from here.

I am almost sure that the reason for the machine to be dead was only the bad capacitors i replaced, so if i only had replaced the capacitors and not started to remove the adress board, i would have had a working machine. roll

Any information or Pictures of a working 128K machine would be much appreciated.

kluder · 08-09-2017 04:44:25

Hi

I myself have repaired a NewBrain with 128 Kb, and in this connection made a diagram of the print and connection to the main board

Posted as pdf. here
http://www.newbrainemu.eu/components/co … -128Kb.pdf

Hope it can help you
I hope you also get it to life again

greeting
Klaus

use google to translate

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#1 15-08-2017 10:09:42

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#3 08-09-2017 04:44:25

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