[TenTec] Paragon is it dead?

[Mike Bryce]

FYI….

The last Paragon I worked on had about the same issues. I traced the problem to two common CD4000 series ICs in the rear left corner of the mother board. It’s been so long that I don’t remember the number of the chips. They are common off the shelf parts.

That cured the goofy logic board problem.

MIke, WB8VGE


Mike Bryce
prosolar at sssnet.com



> On Sep 14, 2016, at 12:42 PM, Louis Ciotti <lciotti1 at gmail.com> wrote:
> 
> Fresh battery is in place.
> 
> I really thing it is either a dead CPU or the EEPROM got scrambled.  I
> found a source for a low cost CPU so I ordered it.
> 
> When looking at the signals with the O'scope, the IRQ line does not look
> right:
> 
> https://goo.gl/photos/6ohJcT8Lu4qrSsVp9
> 
> All the other logic line look nice with out the finky ripple on the lines.
> If I remove the CPU this line goes to nice smooth a logic high, which is
> what ll the digital line with a logic high on it look like.
> 
> If I swap the CPU and that does not cure it, I am going to say the EEPROM
> is dead.
> 
> I wonder if TenTec would have the source code for the 6805 assembly code,
> or the EPROM image stored somehwere and I can re-burn since it looks like I
> can still get the eprom as well, I just would need to get a burner.
> 
>