The April 20th 1970 newspaper article did not show an image of the apartment wall, it only mentioned the "Satan Saves Zodiac" writing, and descrbed the drawing on the wall as "a weird cross like design with an arc, similar to the Zodiac's circled cross insignia". It made no mention of an Egyptian Ankh. The image at the top of this article was taken from the San Francisco Chronicle newspaper article released on April 21st 1970.
In the Zodiac Killer's short code, he added the Celtic Cross, three circled eights (which represents the name Jesus in Christian numerology) and the Christian anchor (a symbol of hope in future existence for many Christians). All the symbols have a religious connotation. The image on the right is a Christian anchor. The word "anchor" has the same phonetic root as the Egyptian "Ankh". However, the interesting aspect of the Christian anchor, is that its imagery comprises that of the crude anchor Zodiac placed in his 13 character code and the drawing of the Egyptian Ankh placed on the apartment wall of Robert Michael Salem. A drawing he should have had no knowledge of on April 20th 1970, because that image wasn't released until April 21st 1970. Not only do we have the 888 of Jesus Christ and "Satan Saves" connection, but we have the Christian anchor being a combination of Zodiac's crude "code anchor" and the yet to be released image of the Ankh, discovered the night before. Was this another coincidence, or was the Zodiac Killer responsible for the murder at 745 Stevenson Street?
FOLLOW UP ARTICLE: ROBERT SALEM-A ZODIAC MURDER?