I’m kind of big on schematic diagrams, but I wasn’t always so. Below is the schematic diagram I developed for the little radio. I now had a crystal radio put together as it should be and it worked – sort of. The slug is held inside the tube by wax and if you are careful and apply slow, even pressure, the slug will move to where you want it. By moving the slug, I was able to match the dial to about where I knew my local stations were and was able to hear the Mexican station near the top of the dial.

To match the dial with the AM band, I took a thin wooden stick and gently pushed on the ferrite slug in the coil form until it was nearly centered between the two sets of coils. At the very top of the AM dial (around 1600) I know there is a very strong Mexican station, but I couldn’t go high enough to tune it in. When I finished soldering everything in correctly, I connected the little set to my antenna & ground and soon I could clearly hear my local AM stations, but I noticed that the tuning dial seemed to be way off. The antenna coil is to the left of center.Ī powdered iron (ferrite) slug is inside the tube between the two coils. The antenna and the station tuning coils are wound on the phenolic tube. How to format g drive for mac into exfat drive.īack side showing the radio’s components. This replica of the original double-tuned Heathkit CR-1 crystal radio closely follows the specifications of the authentic radio of the 1950’s by the Heath Company: This clone first was thoroughly analyzed, researched, and then masterfully built by radio guru Scott Balderson in his home shop. It was a double tuned crystal radio from the 1950’s with a series tuned primary that had a 365 pf variable capacitor and selectable additional capacitance on the center selector switch. This page gives the circuit and pictoral description of the famous Heathkit CR-1 crystal radio. I have made a working prototype of a small and cheap crystal radio based on the Heathkit CR1 A crystal radio project for advanced students and hobbyists If you like reading about building home made radios up from scratch, perhaps you would like My Magnum Opus homebrewed ham radio project.

High performance Heathkit CR1 crystal radio. Heathkit crystal receiver schematic model cr-l. 5mmf:1 200 si c3 ic4, switch 365 3501 350 mmf mmf mmf li antenna gnd. Headset crystal diode cri 100 transformer iiiil2 i det c2 iiiil. A very selective and high performance crystal radio

Heathkit cr-1 crystal radio manual