Basic Radio Project

[baffled by electrons]

Was hoping someone out here could help me with a radio project. I know almost nothing in the electronics field, but I am helping an inquiring young mind about science & radio waves. I bought a radio project from the store, you know the kind with the aluminum foil variable capacitor. I'm looking to step it up a bit! I was hoping to find a project that used a real air variable capacitor. Would like to learn a little about radio astronomy by listening to the sun. I can't seem to find anything online that I can even comprehend. Any help is greatly appreciated. Thank you.

 

[Hero999]

Air spaced capacitors are expensive because they're seldom used these days.

 

[KMoffett]

When you find a project, and need a source for air variable capacitors look at Ocean State Electronics **broken link removed**.

Ken

 

[Hero999]

It's good to see they're still made when you consider that plastic capacitors can be bought for a tiny fraction of the price.

 

[ericgibbs]

Was hoping someone out here could help me with a radio project. I know almost nothing in the electronics field, but I am helping an inquiring young mind about science & radio waves. I bought a radio project from the store, you know the kind with the aluminum foil variable capacitor. I'm looking to step it up a bit! I was hoping to find a project that used a real air variable capacitor. Would like to learn a little about radio astronomy by listening to the sun. I can't seem to find anything online that I can even comprehend. Any help is greatly appreciated. Thank you.

hi,
Try your hand at this, looks easy enough.

Build Your Own Air Variable Capacitors!

EDIT: or buy.

**broken link removed**

http://www.midnightscience.com/catalog5.html

**broken link removed**

 

[baffled by electrons]

Thank you all for your help! I have seen "Build your own air variable capacitors" and thought about giving it a try.

If my research is correct our sun's frequency is 406.10 - 410.00 MHz. If that is correct how big of a capacitor would I need? Does a coil size and/or antenna matter?

Also I have the feeling by doing a little more reading on this site that I may have posted this to the wrong area. If so I apologize and ask where should I have posted this? And can I move this post to that area?

Thank you all again.

 

[Nigel Goodwin]

Thank you all for your help! I have seen "Build your own air variable capacitors" and thought about giving it a try.

If my research is correct our sun's frequency is 406.10 - 410.00 MHz. If that is correct how big of a capacitor would I need? Does a coil size and/or antenna matter?

That's UHF - and pretty well beyond air-spaced variable capacitors - it's more usual to use varicap diodes at those frequencies.

Aerials and coils are (as always) crucial, but even more so at these frequencies - half an inch of straight wire is a fairly common 'coil' at these frequencies, and construction is critical.

Also I have the feeling by doing a little more reading on this site that I may have posted this to the wrong area. If so I apologize and ask where should I have posted this? And can I move this post to that area?

It's fine here.

 

[JimB]

If my research is correct our sun's frequency is 406.10 - 410.00 MHz.

Where did you get that information? There will certainly be sun noise in that frequency range as well as just about everywhere else.
The sun generates very wideband noise from shortwave through to microwave frequencies.

If that is correct how big of a capacitor would I need? Does a coil size and/or antenna matter?

It is quite easy to hear sun noise, but you will need a receiving system which is several orders of magnitude more sophisticated than a coil and home made capacitor.

I suggest that you have a look here:
The Radio Sun
I googled "sun frequencies" and this was the first hit, it seems to have a lot of information.

JimB