Is this a real patent?

Yes — the original drawing as filed at the U.S. Patent Office, cleaned and printed. Public domain by law.

Printed in Europe on 200 g/m² matte paper. Small sizes ship flat, 50 × 70 ships rolled in a tube. Tracking by email.

What if it arrives damaged?

Send a photo within 7 days and we reprint and reship it free.

US 1,342,885Method of receiving high-frequency oscillations1920

PD-45 · US 1,342,885

Name: Method of receiving high-frequency oscillations Patent Print (1920)
Brand: PATENT DEPT.
SKU: PD-45
Availability: InStock

Armstrong's receiver circuit — the architecture inside nearly every radio built since the 1920s.

Finish

Size

Total29 €

Shipping included (EU)

PD-45 · US 1,342,885 · Filed February 8, 1919 ·

Is this a real patent?: Yes — the original drawing as filed at the U.S. Patent Office, cleaned and printed. Public domain by law.
How is it shipped?: Printed in Europe on 200 g/m² matte paper. Small sizes ship flat, 50 × 70 ships rolled in a tube. Tracking by email.
What if it arrives damaged?: Send a photo within 7 days and we reprint and reship it free.