An Indoor Reduced Size Rectangular Loop

by Yukon John, KL7JR

Be sure to see updates for March, April, May and September 2011 below.

Ever hear of anyone adding coils to loops?

Sometimes indoor antennas are our only means of staying active with Amateur Radio. From the very first time I used an indoor loop, I liked the performance. Would I like one again?

I am on an end apartment on the top floor of a 14 story apartment building. This concrete building withstood the Alaska Earthquake of 1964, so it no doubt has a lot of rebar in it.

Rebar would cause a lot of interference I thought. Right? There is only one way to find out.

I spliced together some scrap speaker wire (photo 1 below) that I had to fit my living room wall 19 feet long by about 6 feet wide (just staying about a foot above the floor) and thumb tacked the wire to the sheet rock wall.
I did not even solder the splices or feed point connection (photo 2- the flower vase keeps my cat away!) which was one foot up from a lower corner.

I may install a balun later if I get tvi complaints.
Using the loop formula (1005 divided by frequency in MHz) I was just short of three-quarters WL on 20 meters. It would either work or not I thought.

I spent the first weekend testing the antenna which was actually quieter than I thought it would be with noise levels of S1-S2 when VE6FI answered my first call and gave me a 5x8 report. Then I worked VA7TT, JA7FTR, KH6LC, VE3EJ and several others on 20 meters and a few east coast stations on 17 meters as well.

With an ATU the loop works 10-20 meters and perhaps 40 meters as well! By the second weekend of casual DXing (early November 2009) with improving band conditions, I racked up 6 countries and 18 states. If I could hear them I could usually work them and the sent and received reports were the same 75% of the time.

I think I will leave the loop up awhile! The moral of the story:
Indoor antennas do work, and sometimes very well!