Hackers' Pub

Syntax	Description	Examples
`"` keyword `"`	Finds the string within quotes, including spaces. Case-insensitive. (Escape quotes inside with `\"`)	`"Hackers' Pub"`
`from:` handle	Finds content written by the specified user.	`from:hongminhee` `from:hongminhee@hollo.social`
`lang:` ISO 639-1	Finds content written in the specified language.	`lang:en`
`#` tag	Finds content with the specified tag. Case-insensitive.	`#HackersPub`
condition condition	Finds content that satisfies both conditions on either side of the space (logical AND).	`"Hackers' Pub" lang:en`
condition `OR` condition	Finds content that satisfies at least one of the conditions on either side of the OR operator (logical OR).	`#HackersPub OR "Hackers' Pub" lang:en`
`(` condition `)`	Combines the operators within the parentheses first.	`(#HackersPub OR "Hackers' Pub" OR "Hackers Pub") lang:en`

Dan Ports @dan@discuss.systems

8/31/2025, 3:17:26 AM

Public

This is what pull requests used to look like.

(The last sentence is particularly remarkable!)

APOLLO SPACECRAFT SOFTWARE CONFIGURATION CONTROL BOARD PROGRAM CHANGE REQUEST
Number: 848

1.1 Originator: D. Eyles, Date: 7/22/69, Organization: MIT/IL
1.2 Approval: George W. Cherry, Date: 7/23/69
1.3 Effectivity: Luminary 1B
1.4 Title of Change: Prevent RR ECDUs from Stealing LGC Memory Cycles
1.5 Reason(s) for Change: See attached Data Amplification Sheet.
1.6 Description of Change: See attached Data Amplification Sheet.

3.0 MIT VISIBILITY IMPACT EVALUATION:
3.1 Schedule Impact: 0
3.2 Storage Impact: ~8 words
3.3 MIT Coordinator: George W. Cherry
3.4 Remarks: Approved by T. Price and T. Gibson on 7-22-69

(and many blank fields)

APOLLO SPACECRAFT SOFTWARE CONFIGURATION CONTROL BOARD
DATA AMPLIFICATION SHEET

PROGRAM CHANGE REQUEST #848 8
PREPARED BY: D. EYLES
DATE: 7/22/69
ORGANIZATION: MIT/IL

CONTINUATION SECTION (REFER TO BLOCK NUMBER AND TITLE
ON PROGRAM CHANGE REQUEST FORM)
1.5 Reason(s) for Change
Because when the Rendezvous Radar Select Switch is not in the LGC position, the RR resolvers are being excited by an 800 cps signal which is not necessarily in phase with the 800 cps reference of the RR CDUs, these CDUs are likely to go to their maximum rate mode (6400 pps each). This behavior snatches a total of 12800 memory cycles every second, or 15% of LGC time, and can result in 1201 and 1202 software restarts.

1.6 Description of Change
Monitor the RR Power On/ Auto bit (bit 2 of Channel 33) and set the Zero RR CDU
bit (bit 1 of Channel 12) when this bit shows that either the RR circuit breakers are
pulled or the RR switch is in AUTO TRACK or SLEW.

REMARKS
It was the misbehavior in question that jeopardized the lunar landing of July 20, 1969.

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