Some of the electrical parts, notably the “Fixed Crystal Detector” and the mica condenser were products of Electrical Research Laboratories (ERLa) of Chicago, Illinois. RadioMuseum.org assigns the condenser a 1923 production date. ERLa made radio parts, kits, and complete radios.
References and Resources:
RadioMuseum.org has a page describing the ERLa fixed crystal detector
https://www.radiomuseum.org/r/erla_fixed_crystal_detector.html
Reference page for ERLa created by Harvard Museums of Science & Culture
http://waywiser.fas.harvard.edu/people/3129/electrical-research-laboratories-inc