shop-built triode?

Cruft Laboratory, Harvard University

Object number: VT0204

Cruft Laboratory, Harvard University

Object number: VT0197

Cruft Laboratory, Harvard University

Date: 1921

Object number: VT1021

Cruft Laboratory, Harvard University

Date: 1921

Object number: VT1020

Cruft Laboratory, Harvard University

Object number: VT1549

Cruft Laboratory, Harvard University

Object number: VT0515

Cruft Laboratory, Harvard University

Object number: VT0516

Cruft Laboratory, Harvard University

Object number: VT1311

Cruft Laboratory, Harvard University

Object number: VT0220

Cruft Laboratory, Harvard University

Object number: VT1298

Cruft Laboratory, Harvard University

Object number: VT1605

Cruft Laboratory, Harvard University

Date: 1938

Object number: VT0224