Continuing from my last post (and thanks to u/Ancient-Ad-7453), I have uploaded a picture + video of the behaviour before adding cables.

https://preview.redd.it/rdbyuitk7g9h1.jpg?width=1200&format=pjpg&auto=webp&s=e50dbec1bcd0603a552ae15279b8ff13c7d506ea

register behavior with no cables typing

I have connected 4 red wires from the first ls173 (pins 11, 12, 13, 14) to VCC. The Enable and load were connected to VCC to start.

• with Load set low, corresponding LEDS for pins 3, 4, 5, 6 on first LS173 connected to pins 2, 3, 4, 5 on LS245 are constantly on while LEDs on pins 5 and 6 vary on and off

first ls173 outputs

first ls173 vcc connections

I tried using the 4 red wires on the second ls173, connecting pins 11, 12, 13, 14 to VCC, starting with enable and load set to VCC.

• With load set low, corresponding LEDS for pins 3, 4, 5, 6 on the second ls 173 (connected to pins 6, 7, 8, 9 on ls245) are constantly on, while LEDs on pins 3, 4 vary between on and off.

second ls173 outputs

second ls173 vcc connections

Major thanks to u/HydroPage for the link on series resistors, I have made some adjustments and recorded new observations. The register seems to take on data now, however it seems like there are still a few issues.

(Realizing as I post, I made a slight mistake in arrangement so the first LED from the top is pin 4, pin 3 is the second LED, then pin 5 = 3rd LED, pin 6 = 4th LED. I will refit these wires in the next attempt. Ive made sure the descriptions below take this into account)

https://preview.redd.it/8fvi2r5rwn8h1.jpg?width=955&format=pjpg&auto=webp&s=b67fe1bdae48a50ceffd6418fc06fd09135ceb9e

• At first I tried 1k resistors in series with LEDs, assuming they would be safer to start with, expecting the LEDS to be dimmer too. Only pins 4 on the first LS173 (closest to the LS245) and LEDS on pins 4&5 for the second LS173 light up.

https://reddit.com/link/1ubuft1/video/svcrec7iwn8h1/player

• I replaced the 1k resistors with 220 ohms with Load set high (VCC), all LEDs were on except on pins 4&5 on the first LS173.

220 ohms with load set high

• I set load to low, LEDs on pins 3&4 for the first LS173 flash and pins 5&6 on second LS173 flash. Flashing has no pattern and after a while, all register LEDs go out.

220 ohms with Load set low

This is a new account I made just for electronics projects, so apologies if formatting is off. I’m trying to diagnose an issue with the register module in Ben Eater’s 8‑bit computer build, but I’m getting some really strange behaviour and I’m not sure what it indicates. I’ve attached pictures and a step‑by‑step description of what I tested and what I observed. At no point were any of the chips hot/ overheating. Below are some of my notes, I apologise if its unintelligible and will record videos for the next update. Any advice is appreciated.

Clock module (works)

• Powered VCC 5v, blue light output is fine
• GND cable connects clock to register

Connecting VCC line of Clock to Register

The GND cable connects the clock module to the register, HOWEVER
to test if there was any power being received by the register, I DID NOT connect the Clock from pin 7 of the LS173s to the Clock at this stage.

Observed Behaviour:

• All clock lights go off immediately
• Register lights pin 4 and pin 6 on both LS173s light up
• Sometimes just pin 6 of LS173 closest to LS245, and pins 4 and 6 on LS173 furthest away light up
• When turning the power supply off and then on again, clock output and yellow lights (astable, monostable and bistable) all light up as normal.

Connecting VCC line of Clock to Register, chips labelled

different angle, quality of the first picture was not great

Connecting Clock line (Blue) from Clock to Register (pins 7 on LS173s)

I kept GND connected and removed the VCC line which connects clock to the register.

Observed Behaviour:

• Clock circuit stays flashing at normal rate
• Register red LEDs; pin 6 on first LS173 (closest to the LS245N) and pins 4, 5 and 6 on the second LS173 are flashing
• If astable circuit has been selected, red LEDs flash at the same rate as the clock output
• If monstable circuit has been selected and monostable pulse ticks are manually input, pins 6 on the first LS173 (closest to LS245), and pins 4 (and sometimes pin 6) on second LS173 light up. Red LED on pin 4 for the 1st LS173 stopped lighting up.

Astable circuit has been selected, red LEDs flash at the same rate as the clock output

Clock connected to register, VCC line not connected between clock and register

Monostable inputs lead to only pin 4 of the second LS173 lighting up

Monostable inputs lead to pins 4 and 6 of the second LS173 lighting up

astable pulse rate on the LEDs

After this, I took the clock line out, restarted the power supply and saw pin 6 on the first LS173 no longer lit up, but LEDs on second LS173 pins 4, 5 and 6 were on.

Clock, GND and VCC connected

Clock output light all immediately turn off as soon as VCC connects clock circuit to register, however the first LS173 pin 4 and pin 6 LEDS are on, second LS173 pin 4 LED is on for the register.

Starting again after connecting VCC, Clock output was flashing as normal but with first LS173 Pin 6 LED constantly lit, second LS173 pin 4 and pin 6 LEDs constantly on. I connected the clock line after, pin 6 LED of second LS173 flickered, then the first LS173 pin 6 and LEDS on pins 4 and 6 on second LS173 remain on.

I moved load (pin 6) to GND. The LEDs lit up in random order is the clock flashing, then clock goes out. Pin 3 LED on first LS173 and pin 6 LED on second LS173 remain on.. Turned off the power I saw pin 5 on the first LS173 flicker.

Reconnecting the clock line after turning power supply on again and then connected VCC from clock to register, pins 4 and 6 on the first LS173 and pins 3, 4 and 6 on the second LS173 are flashing but on the "offbeat" -- when clock output (selected astable) current is not lit on. Load line set to low / GND does nothing.

astable selected, output is on. LEDS on register are off

Astable/ output is off, register LEDS pin 4 + 6 (first LS173) and LEDS on pins 3,4 and 6 on second LS173 are on (\"offbeat\")