Michele, thank you your note above led me to find a couple of places I haven't used before. While I have dna information about my father's father, His name, age in 1906-7, town of residence or birth, and date/place of death have been nowhere visible to me. But there's a web site where written records where these MIGHT be found (see the url below) because information about Jews' existence was legislated as necessary in pre-Holocaust years.
Inside Familysearch: https://familysearch.org/wiki/en/German_Jewish_Records#Baden.2C_Wuerttemberg.2C_and_Hohenzollern (Baden seems to be the right area & era (but is it? the town of my father's birth is Frankfurt, but his conception could very well be Karlsruhe; and furthermore : Leo Baeck Institute
"The Leo Baeck Institute in New York has a collection of 50,000 German Jewish records, primarily from Baden, Berlin, Schleswig-Holstein, Westpreußen, and Württemberg. These include circumcision, marriage, death, and memorial records. The following work describes the collection:
Grubel, Fred, et al. Catalog of the Archival Collections [of the Leo Baeck Institute]. Tübingen, Germany: J. C. B. Mohr, 1990. (FHL book 974.71 A3gf.)
Much good information can be found at: www.lbi.org , web site of the Leo Baeck Institute."
Wikitree's JEWISH ROOTS and GERMAN ROOTS projects may be interested too.