RFI Snapshots

Grow lights on 80

Grow lights on 80

A set of pages showing snapshots from various SDR radios of what different types of RFI look like has been added to the site.  Just click here to go to the RFI Snapshots set of pages.

The images are broken out in categories for each type of RFI.  You click the category, and that takes you to a number of different images of RFI, as captured via SDR.

If you have an SDR, or Spectrum Analyser capture of any sort of RFI, and you KNOW without a doubt what that source is please email it to me, I will add it to the growing number of snapshots that exist now.

Categories: Info, RFI Mitigation, RFI Signatures | Leave a comment

Notes on tuning a Hustler 6BTV

80 Meters, no choke, 8 radials.

80 Meters, no choke, 8 radials.


I thought I would share a few of my notes on tuning up a 6BTV antenna, and constructing a radial field.  I have been using a GAP Challenger DX, (review here), for the past fifteen years, unbeknownst to me, and over that time, water had been slowly seeping into the tuning harness of the antenna.

The harness finally gave up the ghost one day, presenting a dead short to my Solid State ALS-1306 amp, (review here), as I increased power.  At about 800 watts CW, the harness shorted out, killing the ALS-1306, and necessitating the amp make a trip back to ALS-1306 heaven, (Ameritron), to have a replacement RF output device installed.

Replacing the Challenger was one of the options on the table, but I did not want to do a new install of a Challenger– I remember the last install.  The entire phasing harness installation process is not fun, nor is it easy, so– given there were a few things about the Challenger I was not happy with anyway, I began looking for a different antenna.

Read more »

Categories: 6BTV, Antenna Reviews, Construction, Info | 8 Comments

Using a SDR as a RFI site survey tool


Twenty Four hours of RFI on 80 Meters

Twenty Four hours of RFI on 80 Meters

This is Part One of a multi part article dealing with setting up a SDR as a RFI site survey tool to assist in RFI detection, location, and mitigation.  Further, part one will set the stage for how captures of the RFI were accomplished, and visualized.  Part one will also  touch upon some of what can be seen and learned from this data.  Methods I used to locate RFI can be found here.  Also some RFI sources signatures have been captured here.

Part two will deal with optimizing the display in order to show different types of RFI, while making the survey tool portable,  Part three will deal with actual location methods, using that portable SDR tool.

Read more »

Categories: Cleanup, Construction, Digital, Info, Quantification, RFI Mitigation, SDR as Site Survey tool, Tools | 13 Comments

Review of the Palstar AT2KD Tuner

AT2KD Tuner, front view

Palstar AT2KD Tuner

This review of the Palstar AT2KD tuner will start off with a few comments about tuners in general, and will not get too technical.  There are many other places to find technical reviews of this device…  eHam ratings indicate that it is a 4.8 out of 5, which is a pretty darn good rating, and some pretty good technical reviews there as well.

Over time I have had both auto tuners, and manual tuners.  I have used differential tuners, and standard tuners…  I always return to manual tuners, using roller inductors, and large caps every time…  An auto tuner is simpler to operate, but the power levels just are not there yet for me on anything I can afford, nor have I been able to get an autotuner, (of the ones I have used), to tune to an exact 1:1, every time, on every band.  It is always something like 1.x:1, I have seen as high as 1.7:1, which can cause issues with the new solid state amps, such as the ALS-1306, which I own.  See the section under “Conclusions”, for more on that subject. Read more »

Categories: Accessories reviews, Info, Palstar AT2KD, Reviews | 2 Comments

Adding an external keypad to the K3

Genovation KeypadThis article on adding an external keypad to the K3 was created to make it simpler for the next poor sod down the road to add a Genovation CP48USBHID, 48 key keypad, or the Genovation CP24USBHID, 24 key device to their K3/P3 devices.  I initially learned about the Genovation keypads on the Elecraft mail list.  It sounded to me like several people were talking as if they had them working, so I asked how to set one up, and got nothing back…  I asked again a few weeks later, only this time on both the Elecraft, and the Yahoo mail lists.  I received several replies, all saying they would like to have one of these working as well.  I did get one lone reply from a person who said, “yes, but I did it a year ago, and have now forgotten how”.  From that I concluded I was on my own in getting these two devices connected.  Given I agreed with the general premise that having a keypad available to send macros to the radio would be good, I decided to move forward with this project and see how far I might get.  I contacted the Elecraft support team first, and got, “only the listed keyboards will work”, response.  However, in the discussion, I got what would later turn out to be a vital piece of information in making the connection between these two devices work. Read more »

Categories: Elecraft K3, Info, K3: External Keypad, Reviews, Setups, Software information, Station | 32 Comments

I have RFI, now what– Locating it

FFT of RFI showing 10 hours of noiseAs the name suggests, this article, “I have RFI, now what– Locating it”, will show how I located several RFI sources in my area.  This is part three of a three part series–  Part one covered what tools I needed to locate RFI, while Part two covered internal removal of RFI sources within the shack, and finally, Part three covers how I located a number of RFI sources external to the shack, and how I got them corrected.

Over the past few years, I have been plagued with RFI on 40 and 80 Meters.  Most of it has been Horticultural lighting, (read that as Grow Lights), and most of it has been pretty easily located.  In fact most have been found in under 15 minutes!  For the most part the folks I have contacted have all been decent types, and have all to a fault, done what it takes to either remove the RFI, or stop generating it.  For that I am thankful to them, it saves me the time in getting the Federal Communications Commission, and the ARRL involved.  It also saves the person generating the RFI, the problem of federal involvement.

I suspect a lot of this “good luck” has been because I never threaten, or wave the Federal Communications Commission at anyone.  I simply tell them, in writing, what I will do to get the RFI to stop, by giving them a handout our club created, which approaches the entire issue in a kind, friendly manner.  The goal is to solve the RFI problem at the lowest possible level, not just go straight to the Federal Communications Commission, but to give the person a chance to solve the issue locally, so I don’t have to involve the Federal Communications Commission. Read more »

Categories: ARRL, Direction Finding, DX, I have RFI: Series, Info, Legal Actions, MFJ: MFJ-856, Quantification, Reviews, RFI Mitigation, Setups, Software information, Station, W8VVV: S-meter Lite | 2 Comments

Review of Ameritron’s ALS-1306 Amplifier

Ameritron ALS-1306 Front view

ALS-1306 (Front)

This review of Ameritron’s ALS-1306 was prompted by my selling my older ALS-82 in order to get a no tune amp.  This will not be a technical review, as there are many of those around, and the amp is based on the older designed ALS-1300, with some protection added.

I decided that I wanted an auto tuning amplifier, as opposed to the manual tune, AL-82 I was using.  So I sold the old AL-82, (see my review here), and purchased an Ameritron ALS-1306.   Read more »

Categories: Accessories reviews, Ameritron: ALS-1306, Info, Radios reviews, Reviews, Service reviews, Setups, Station | 44 Comments

Review of “DX World”


DX World Logo

DX World Logo



Several months ago I did a review of “The Daily DX“, and now it is time to do a review of “DX World“.  One is for pay, and one, (DX World), is free.  Yes, free, “DX World” is totally free to the user.  I did not want to do a review without having actually used DX World for a bit, so I started using DX World on a daily basis the day I did the review of Daily DX.

Read more »

Categories: DX, DX World, Info, Propagation, Reviews, Service reviews | 2 Comments