Low Band Grounded Loop

The ARRL told me that they do not plan on continuing to update this book with new revisions. If you don’t already have it – you really need to order yours now – because it is already a classic.  More than ever, the combination of Low Band Antenna Experimenting and Maker projects is the cats meow in Ham Radio. I don’t even care so…

Steps to the Son of Mod Bob . . .

I have three aluminum elements up for the Mod Bob and will take down the center element: I already have a coax cable running from the Array Solutions switch you see to the left that goes all the way to that far element. The outside elements have the wire attached and it comes down to the center via a cool resin plastic (DXE) guy…

Benefits of Son of Mod Bob

There are several things that will be big benefits from Son of Mod Bob: I will remove the center element which is way to close to my 40M vertical array. This will eliminate the distorted 40M pattern I will no longer turn on the Trane HVAC when I transmit at full power I get three antennas in one, a half square on 40, Inverted…

Son of Mod Bob!

Son of Mod Bob! Page 14-7 from the ARRL ON4UN Lowband DX-ing book Chapter 14 in the ON4UN Lowband DX-ing book is a gem. John shows how to take a 40M half square and feed it just like the grounded loop – and where it then is a close array on 80M with gain. The dimensions in the book call for 72′ wide and…

The Grounded Loop Antenna (Thanks Jan, OM2XW!)

The feed is a simple L-C circuit, left, and the antenna can be switched between being an Inverted U or Grounded Loop, right Jan, OM2XW, wrote and reminded me of an antenna that is in the ON4UN Lowband Book, and one I have never tried. AA7OK has a VERY nice write up with great references at his web site – http://litlisten.com/aok/ As I understand it –…

Inverted L vs. Inverted U vs. Mod Bob

Inverted U on 160, 80 and 30 and half square on 40M Just for laughs, lets compare three antennas that I could have – against what I have now – the “Mod Bob”. An Inverted L would be MUCH better than the Mod Bob. Its something I need to consider – because I could use the u.RAT to tune it. On 80M, the Mod…

Pacificon 2017

I will be presenting during the Pacificon 2017 Antenna Forum on Friday, October 20, from 3:30 – 4:30, and my topic is “Low Band DXing Antennas”. I will start with a survey of all of the low band antennas that you should consider for DX-ing on the bands 160 – 30M, and I will include transmit as well as special receive antennas. The presentation…

The Best Two Antennas I Have Ever Had

For all low bands, 160-30M, my own designed “Modified Bobtail” is a very clear winner. I’ve blogged extensively about this antenna, and the best antenna tuner for this antenna – and my favorite antenna tuner of all time is the Palstar BT1500A. Every feature, knob and button is useful and perfect for the Mod Bob. The best yagi antenna I have ever had was…

Final Notes on the U.RAT

I installed the URAT out back at the base of the “Mod Bob” antenna. I experimented for a few hours and I was able to get a decent SWR on 160, 80, 40 and 30 by doing this: 160M – bypass the capacitors and use a shunt coil at the antenna feed 80M – use the capacitors with that same shunt coil 40M – same…

U.RAT Version 2.0 and Experiments

The u.RAT that I will set up tomorrow will replace the Palstar BT1500A, but only as a test – to see if two Palstar C600 variable capacitors plus one inductor will work on 160M. I expect it will work on 160 and 30M, but not sure about 80M. I split the control box and the drivers so that the Raspberry Pi Zero is in…