Spacelog Apollo 8

You're unreadable, but request that you end your purge.

Roger. We ended our purge.

Apollo 8, Houston. Over.

Go ahead, Houston.

Roger, Jim. I've got a short procedure I would like to read up to you on your DSKY, and I'd like to explain what it is. Your W-matrix shared some memory locations with P01; therefore, the W-matrix that you have right now is not a good one, and we would not want you to continue your P23 sightings with that matrix. So the procedure I'm going to give you is going to cause the matrix to reinitialize itself prior to your next P23, when you go into P23. And this will put you back with the value of the W-matrix which you loaded after TEI, you remember, that 3303 thing. And if this has any further effects on the flight plan, we're in the process of sorting that out, and if need be, we'll send you up a revised sighting schedule later, both with the COMM and loss of COMM case. Over.

Okay. Stand by, and I'll get something to copy with.

Okay.

Okay. Go ahead.

Okay. Insert without releasing the flashing VERB 37 the following: VERB 25 NOUN 07 ENTER, 77 ENTER, 40 ENTER, ENTER, VERB 37 ENTER, 00 ENTER. Over.

Understand. We insert VERB 37 without releasing, is that correct?

Roger. You should have flashing 37 on your DSKY now, and without releasing that flashing 37, go ahead with the VERB 25, et cetera.

Roger. Okay. I see what you mean. Okay. We'll insert VERB 25, NOUN 07 ENTER, 77 ENTER, 40 ENTER, ENTER, reinsert VERB 37 ENTER, 00 ENTER.

That's all correct. Say, if you've got any questions about that, we would be happy to answer them.

Roger. Are we cleared to do that now?

That's affirmative, Jim.

Roger.

Hey, Mike, this is Frank.

Go ahead, Frank.

Is there any danger that this might have screwed up any other part of memory that would be involved with entry or anything like that?

Frank, all indications are that there is absolutely no problem with anything in the computer memory other than the W-matrix. However, we are continuing to look at it, and if there is any doubt in our mind, we will ask you to dump the memory locations for us later. Over.

Apollo 8, Houston.

Go ahead, Houston.

Roger, Jim. We thought you might be interested in knowing, based on 2-1/2 hours worth of track after your last midcourse, and looking ahead, we're predicting the midcourse correction at 122 hours will be less than 1 foot per second. And keep it on going to entry interface minus 2 hours, we're predicting 2 foot per second midcourse at that time. Now those numbers will be refined; we'll get about another 8 hours of track on you before we amend them. Over.

Sounds like we're on pretty good trajectory.

Can't hardly beat it.

No, I'm right here. We're going to start doing cislunar NAV right now, and Bill's up in the left-hand seat.

Roger. Understand; you're going to do some P23's now. We thought you were going to take a rest and do them later.

No, Frank is asleep now. We'll get these out of the way. So I'm coming over to do a trunnion alignment at this time, and then we'll go into the P23.

Okay, Jim. There's one thing before you get started on the P23. What we told you before, we still think is absolutely correct. The only thing in the computer memory that is changed by that P02 is the W-matrix. However, as an additional precaution, we'd like to dump the computer memory and go through it and check it bit by bit and make sure everything is exactly copacetic. Over.

Okay. Do you want to do that now?

Affirmative. We're getting Goldstone configured for it; it'll be just a minute. And while we're doing that, I can read you this procedure if you're ready to copy.

Okay. Stand by one, and I'll be ready to copy pretty soon.

Thank you.

Go ahead.

Okay. We'd like a VERB 01 NOUN 01 ENTER, 333 ENTER, and then we'd like for you to read us register 1. Register 1 we expect will be a 10 000, and if register 1 is equal to that, then what that means is that the computer will dump its erasable memory twice. That's 10 000 numbers, twice number for the erasable memory dump. If it's not reading 10 000, then we'll ask you to make it read 10 000 by going VERB 21 NOUN 01 ENTER, 333 ENTER, 10 000 ENTER. After you've done that, the dump VERB is VERB 74 ENTER, and that will automatically dump the total erasable memory twice, and return you to the proper configuration.

Okay. The procedure will be VERB 01 NOUN 01 ENTER, 333 ENTER, and read out register 1. Then 10 000—the memory—the computer will then dump the memory twice as properly configured. If not, we have to load in 10 000, and we do that by going VERB 21 NOUN 01 ENTER, 333 ENTER, 10 000 ENTER, and VERB 74 ENTER. Now if register 1 does read 10 000, then we'll still have to do the VERB 74 ENTER, is that correct?

That's affirmative. That VERB 74 ENTER is what starts the dump. Then we just prior to that want to make sure we got 10 000; we made sure. And just hang loose one on Goldstone down here; we're getting it configured.

Roger. You need the high gain, Mike?

Apollo 8, Houston. Goldstone is all ready, and you can go ahead with that procedure, Jim.