Repaired typewriter now working; ran 1132 diagnostics to finish off that controller logic testing

CLEANED THE CONTACTS, REASSEMBLED THE SWITCH AND PUT BACK IN TYPEWRITER

The contact oxide coating was thick but I got it cleared off, allowing a low resistance connection in the normally closed position of the CB5 switch. The CB2 and CB7 switches were already conducting with low resistance, thus the CB Response signal will be properly generated now.

RAN 1132 DIAGNOSTICS, TYPEWRITER WORKED PROPERLY

The console printer is no longer permanently busy, allowing the diagnostic monitor to write the status messages as it ran. With this resolved, I then put the printer through its paces to verify that all parts of the printer controller logic are working in the 1130. 

The diagnostic features a number of tests, among them:

1. Wait through 200 cycles with no printed characters, reading the emitted character as the print wheels turn. This verifies that the 48 character codes are read correctly in the proper sequence that matches the physical print wheels. 
2. Sets bit 15 of the word at x0027 (end of the printer scan buffer in memory) to 0, then verifies that the printer detects a scan error.
3. Issues line space commands both with and without the printer on to verify operation
4. Prints a ripple pattern so that each character moves a column rightward per line
5. Prints all the characters of the print wheel, one character per line
6. Spaces 16 times and records which channels are punched on the carriage control tape at that line. It then does skips to specific channels and verifies that it reached the correct point.

Test 6 could not work properly with no carriage control tape installed, as is currently the case. A tape must be punched with no more than 16 total holes. The absence of a tape appears to have 8 holes punched on every line, so we will violate the test by the third time it spaces. 

If I can find any carriage control tapes, even blanks, I can set up a tape for use with the test. So far I have not located them in my workshop. 

RESULTS OF DIAGNOSTIC TESTING

The 1132 printer passed with flying colors. My ribbon is dry, thus the print is light, but you can see that the diagnostics ran well. I stopped the various tests in order to preserve my stock of printer paper. 

In addition to the ripple print and line per character printing above, it printed comments for the spacing tests, such as space 2 with the next printed line starting two down. It verified the emitters, proper code emissions for the characters on the print wheel, and the ability of the printer to detect a Scan Check. 

Some console printer output during the diagnostic run