Sunday, October 20, 2019

Comparing receive signals with and without 1:1 balun.

20m without balun
On Saturday I picked up my Balun Designs 1:1 balun and on Sunday I was able to do some on-air tests. I wanted to see the difference between using the 1:1 balun and not using it. This post will deal with how my receive signal was affected with and without the Balun installed. I was able to take some screenshots from my Icom 7610 for this comparison. The first band I looked at was 20m, it was getting a bit late in the day so there was not a whole lot of action on the band. Even with the lack of signals, I was able to see an interesting comparison. The span on the 7610 was set to 14.000 to
 14.100 to cover the CW and Digi section of the band. The local time was around 22:37 and without Balun Designs 1:1 balun installed the section of 20m from 14.000 to 14.100 showed somewhat I called washout sections. I did notice around the 14.040 mark there is some RFI on the waterfall. When I moved the VFO over to that section the RFI was very faint.  Also a very faint indication of RFI on the waterfall just past the
20m with balun
14.080 mark.
When the 1:1 balun was introduced the band cleaned up regarding the washed out sections. I was able to see Digi signals, in the posted picture the Digi signals are almost gone from the waterfall. There were some CW signals close to the noise floor that I was able to hear (not shown in the picture). I did notice the RFI what was in the waterfall without the balun installed is gone BUT after the balun was installed at 14.080 there was a stronger RFI signal and I could hear it very well when tuned to it. This RFI was not there all the time I would say it was on and off. Not sure what it is but that is not the purpose of this post.....save that for another post.
20m RFI without balun
With the 1:1 balun installed it seemed to clean up the band and bring out signals that were otherwise washed out.
20m RFI with balun
The next band I did was 30m and the span was 10.100 to 10.150 I found without the 1:1 balun installed the 30m band was washed out with just a hint of Digi signals between 10.130-10.140. Once the balun was installed the band cleaned up and there was no longer a washout effect. The Digi signals were much more significant and I also was able to see some CW signals on the waterfall. I did notice just
30m without balun.
to the right of the Digi signals something on the waterfall. I was not really hearing any RFI when I tuned it in maybe it was packet I am not sure?
Because it was later in the evening 40m seemed to really shine when I preformed the comparison with and without the balun installed. The span of 40m was 7.000 to 7.100. Without the balun, there was some CW signals as well as some Digi signals that I noticed. I was pleased with what I saw until I placed the balun in the picture. This cleared up the band and I was able to see more CW signals and the Digi section was much more pronounced. I also noticed according to the S-meter with the balun was around S-4 and without just over S-5.

I am very pleased how the balun has improved the receiving end of things.
30m with balun

30m digital signal with something to the right?
40m without balun
40m with balun

4 comments:

PE4BAS, Bas said...

Wow, a lot of difference. You probabely didn't expect this yourself. I think a balun or RF choke is definitely something to have when using a endfed. I've been checking PSKreporter for your signal this weekend but no luck yet...73, Bas

VE9KK said...

Good morning Bas, yes I was very shocked at the results and for the blog posting I had taken 25 shots of the screen from the 3 bands. I had to sit down over some tea last evening and sort through the ones that suited the post and what I was speaking about in the post.
I have used PSKreporter in the past to check my signal and it shows most of the time nothing. On the other hand I have checked Reverse Beacon Network and had been given many reports to the U.S and some to Europe. I just had never had much success with PSKreporter for some reason. I would get the same results back in Toronto as well.
For digi I use Ham spots and my signal is spot all over the U.S. and all over Europe as well.
73,
Mike
VE9KK

PE4BAS, Bas said...

Hello Mike, for digimode I use both hamspots and PSKreporter. PSKreporter indeed doesn't spot everything. Hasn't the IC-7610 the ability to take a screenshot from the screen. The IC-7300 has. Just press the power button shortly. Probabely the same with your radio. That way you don't need to take photographs. 73, Bas

VE9KK said...

Good morning Bas, yes this is very true......the 7610 does have the same ability to take the screen shot pic's. I always for some reason like to learn the hard way! Who knows how many times I read that too but it just never clicked into it.
73 and thanks for the info Bas,
Mike
VE9KK