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homebrewPosted - 9 October 2012 13:47  Show Profile  Email Poster  Edit Message  
I love vertical antennas. They normally have round patterns. Usually put up in the open away from buildings and trees. Does it look like the building is blocking any good locals?
With your current set up you can try series and parallel tuning.
I think the biggest bang for your buck after the diode switch would be to add a series antenna tuner and matching transformer. The series tuner I use with my balloon verticals at the local park is a transistor radio ferite antenna coil and a variable capacitor in series with the antenna.


Edited by - homebrew on 10/9/2012 3:29:30 PM

Garry NicholsPosted - 11 October 2012 7:55  Show Profile  Email Poster  Edit Message
Hi zlf;

What a good handle for a crystal set guy! Depending on how you build it and your local listening area stations, quite good results can often be had with single coil single variable sets. The main problem for me, up here in near Syracuse, NY, is that a one coil radio (called "single tuned") is subject of short wave interference which can ride in over top of the AM stations. It is usually not "tuneable". That is, adjusting the variable capacitor makes very little difference in the strength of the SW signal.

It would be good if you could describe your approximate location. We can assess SW problems and your local listening environment a bit for you.

If you are using a telephone "corded receiver", you can do a lot better for only a few bucks. I like the crystal earplugs (also called ceramic earplugs) sold by many places, including Mouser (but don't confuse them with the low impedance dynamic/magnetic types which are less sensitive). But they are sometimes temperamental, so if you decide to go that route I would buy 3 or 4 so you can have the pick of the litter.

I also find that TWO crystal earplugs (or any type of HIGH IMPEDANCE headphone) is noticeably better than one. If you get these, wire them in series for better performance, rather than in parallel. Here is a link to the data sheet for some that Mouser carries. You can get them with 2 different size plugs at the ends or no plug, if you check the listings.

http://www.mouser.com/catalog/specsheets/KT-400300.pdf

We can also point you to a site carrying used refurbished old style magnetic headphones, but the price will be $25 to $50 about.

There is also the option of building some headphones out of a pair of ear protectors and some piezo sounders stuck inside.

What kind of variable capacitor are you tuning with?

What kind of bottle is the coil wound on?

It would help to know the orientation of your antenna (e.g., across the room for 10 feet, up the building for 20 feet, across the roof for 40 feet, etc.) and its total length, approximately.

Are you using a ground? What?

Garry

Edited by - Garry Nichols on 10/11/2012 7:59:31 AM

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