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Old 15th Jan 2019, 4:19 pm   #24
ionburn
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Join Date: Dec 2014
Location: Lincoln, Lincolnshire, UK.
Posts: 583
Default Re: "The Works" Crystal Radio

Quote:
Originally Posted by bikerhifinut View Post
A quick google suggests the ST4148 is a zener diode but I think it's as everyone says a 1n4148 100V 1A rectifier. The datasheet says 1V Vf. I think the ST prefix probably indicates the manufacturer?

I'm going to have a look in town on wednesday while we are in and I might buy one out of curiosity. If nothing else I think it could be possible to mod it with a variable capacitor and I might see if there are any strongish signals here in the frozen wilds.
A.
I am not sure about all this buying, but everyone has been warned lol. It's nice to have a kit, but I get far better results with my 84mm ex Superdrug moisturiser jar with multi-tapped 24SWG coil, good old fashioned tuning capacitor, Germanium diode, (probably) 2k ancient headphone plus 1nF capacitor with the same aerial / earth. I was surprised to receive a German speaking station yesterday, but probably just a one off. Cost is perhaps double although sourcing would be trickier.

I plotted a curve for my ST4148. It spot reads about 0.6mA forward at 0.6V (starts conducting around 0.4V).
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