Sinclair ZX80 / ZX81 / Z88 Forums

I have some N4007 - should I use those instead?

This is messy, but it's "open" so you can see what I've done. - probably something stupid, knowing me.

msknight wrote: ↑Sun Feb 25, 2024 4:49 pm I have some N4007 - should I use those instead?

No. They are designed for low frequency use.

Mark

msknight wrote: ↑Sun Feb 25, 2024 5:01 pm This is messy, but it's "open" so you can see what I've done. - probably something stupid, knowing me.

I think I will need to open those pics on a PC rather than my 'phone while crawling around in the loft

Mark

1024MAK wrote: ↑Sun Feb 25, 2024 5:26 pm I think I will need to open those pics on a PC rather than my 'phone while crawling around in the loft

Don't hit your head on any beams!

Just for good measure... measure... geddit? ... this is what's being fed up the /RD line.

Well, after my repeated botched attempts, I managed to short the ground to the 9v and caused some trouble. After reverting the RAM pack and re-bridging the cut connectors... fortunately, the RAM pack is working.... somehow.

I'm doing nothing more until I receive more solid advice, because it's clear that I am at risk of doing some serious damage.

You should use Schottky diodes to pull TTL signals to low!

The diodes and the resistor can be soldered directly to the pins of the connector:

https://forum.tlienhard.com/phpBB3/down ... hp?id=8612

(Perfectly viewable on a 22" monitor)

I have...
1N5822
1N5408
...both are quite chunky.

I also have 1N4007 but Mark has already said those are for low frequency applications.

What do you recommend me getting?

I also have - BZX85C5V1