dmuntz's latest activity

The 4000 SX might have a different motherboard, so I'm not certain. The 4000 and 4000 LX use a non-rechargeable 3.6V lithium battery...

First pic is overall view, next 3 are closeups of wires, 5th is a pic of the simm solder points that look like they were modified by...

This is kind of unlikely, but on mine something must have been a bit off at the factory because there is one column of pins across the...

Make any progress on this? I've been working on a 4000 and a pair of 4000LXs on and off for a year or so. Got one of the LXs working...

Hi all, I've recently opened all of my Vectrexen, and found a ridiculous number of variations of ways the "PWB 35001A" logic PCB was...

Well... I lifted 6809 pins 33 and 36, and connected each via 3.3k resistors to +5V rail. Video is screwy (possibly unrelated...

This is interesting. Lifting pin 33 of the 6809 allows /RESET to hit +4V (consequently lifting pin 36 allows it to hit +3.3V, as 33 and...

Yeah, I tried pulling the 6522 and the AY3-8192 to no effect. Removing the 6809 is the only thing that lets /RESET go high. Also tried...

One other thing I had done after I wrote the original post was I lifted 6809 pin 37, and ~RESET was still driven low.

Hi Dave, Looks like about 160ms from 5V turn on to pin 37 hitting TTL 1. With the 22k resistor,160ms seems reasonable (RC = 484ms)--at...

Problem: ~RESET (6809 pin 37) is always low. All the chips in this system work fine in another system. R208, C228, C229, D201, and R201...