QRP Club

QRP Station => Builder's Corner => Topic started by: vu2nan on August 19, 2019, 16:26:18 UTC

Title: A Chance Crystal Radio Project
Post by: vu2nan on August 19, 2019, 16:26:18 UTC
A vintage unmarked inductor/transformer had been lying neglected in my junkbox for decades and I had to resurrect it.

Resistance checks showed that 2 windings, with a tap each, are terminated in its 6 pins. One measured 70 Ω with a 5 Ω tap and the other less than 1 Ω. A threaded core, with a movement of 5 mm is situated at the top of the unit.

The 70 Ω winding appeared to be suitable for a crystal radio. It was wired up as per the schematic shown below.

More details at

https://nandustips.blogspot.com/2019/06/a-chance-crystal-radio-project.html

73,

Nandu.
Title: Re: A Chance Crystal Radio Project
Post by: PA1CJT on November 06, 2019, 10:28:08 UTC
Hello Nandu,

how simple it can be! Like going back to my childhood building with a minimum of components a simple receiver. People will be surprised hearing a radio station with a unpowered 'thing' with a connected wire and headphone....

73
Kees
Title: Re: A Chance Crystal Radio Project
Post by: vu2nan on November 07, 2019, 03:43:28 UTC
Hi OM Kees,

I guess we have a lot in common, sharing the same ideas and sentiments!

Many thanks.

73,

Nandu.