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Re: Oatmeal Box Radio

Stacking transformers

From: W4HAY Frank
Date: 9/6/99
Time: 2:38:03 PM
Remote Name: 206.228.243.5

Comments

Jim, I've had good luck doing this BUT each transformer has losses, I think around 10% for each transformer. Carrying this to the X-treme, I'm building a modulator for an old Ameco ham transmitter by putting the output transformers from an old Heath VT stereo back-to-back.

From: Lawrence Pizzella
Date: 3/20/99
Time: 1:55:27 AM
Remote Name: 207.92.174.247

Comments

Are you talking about the tinsel cloth covered earphone wires? I have good luck sticking a piece of #16 solid copper or brass wire amongst the tinsel, then wrapping it all with very fine wire like #30 or 32, or finer. A strand from a multistrand wire works good. Then after all is wrapped tightly, solder so that it flows well. Cover with some heatshrink and you have a nice neat and reliable connection. For the last word on this, or if you want to put new tips on the wire, look at

http://members.aol.com/scottswim/index.html

Scott is the expert here, and will help. If you want a new cord or just new tips, talk to him.

I have not had too good of luck with my 20 meter Dipole for Xtal sets. Forget it if you are using a balun. Try using the shield only to the antenna (ungrounded)that might help.

The Oatbox radio shown on this site works good if the antenna is long (lots of signal and capacitance) but might not tune the low freqencies with a short (low capacitance) antenna. Try throwing a variable cap, across the coil. Take a look at Owens variation on the Oatbox radio he calls the Peanut Special, for how to do this. look on

http://www.thebest.net/wuggy/ for more info

Owen has lots of tips on how to get this radio working. Let us know of your success. 73, Larry