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Classified: Antique Radio Demonstration Coherer Sold

Date Posted By Category User IP Address
2023-02-12Login requiredAntiquesLogin required
SOLD!$200 + exact shipping.

The folks at QRZ.com and eham forums were of great assistance in figuring out what this was.

It's a demonstration item showing students how a coherer works. Coherers were primitive detectors in the early wireless days.

It was made by Welch Scientific, which also made all sorts of electrical items for high schools and technical colleges. The relay dates to the 1940's so this is around 75 years old.

It contains the relay, a vintage doorbell, and a glass tube containing metal filings. The bell agitates the filing so they don't get clumped and cease functioning as the detector.

**Please note: The glass tube has an internal crack**

Payment any way the buyer wants.

Buyer must be happy or you can return it for a refund.

A-OK local pickup in Grand Rapids

Contact me for additional photos.