Q: If RF is a high frequency AC signal, why are there plus and minus signs on a balun?

A: Keep in mind that we are usually connecting a ‘BALanced’ antenna to the ‘UN-balanced’ coaxial cable, hence the term BALUN. So, for most regular applications on a single antenna that is ground independent, such as a beam, dipole and many other wire antennas, the balun polarity doesn’t matter. However, polarity markings on baluns become very important for matching phase on multiple antennas in a phased array, such as stacked Yagis. Also, on most 1:1 baluns, the minus side is connected to the coax shield. So, for an antenna that is ground dependent, such as a vertical, Inverted-L or long wire that uses a ground radial system, the positive terminal must be connected to the radiating element and the negative terminal must be connected to the radial system.


ICOM IC-7300 HF Plus 50 MHz Transceivers IC-7300

My new ICOM IC-7300 transceiver has been loads of fun, but the scope was not
displaying the frequency correctly for signals I was copying. I was listening to a
local AM signal on 570 kHz and had to offset the frequency display by 1 or 2 kHz
to have it sound intelligible. Also, the CW signals I had copied on 40 and 20 meters
did not line up exactly.

I installed the latest firmware version (1.14). You can do this by following the
instructions in chapter 15 of the full manual. The update solved the CW issue and
the signals on the scope were exactly where I expected them to show up. To my
horror, there was no improvement with the AM stations. This was very
discouraging and I was just about ready to send my 7300 back to ICOM!

At about the same time, it occurred to me that maybe there was a setting that
may have gotten changed inadvertently. The manual says this could be caused by
“static electricity or other factors” (probably me). I decided to do a reset which
was fairly simple:

1. Tap the “menu” button
2. Tap the “set” button.
3. Tap the “others” button
4. Tap reset.
5. Tap the “All reset” button and follow the on-screen instructions.

“All reset” clears all data and returns all settings to their factory defaults. If you
have settings or memories you want to save, you could try a “partial reset” first
and try the “all reset” if that doesn’t work. I went to the “all reset.” You can also
save your settings to an SD card prior to the reset (recommended).

The reset solved the problem with the scope and copy of AM signals. I know of
other people who had this problem, so I hope this can be of help to you.
73 and enjoy your IC-7300!

Author: Dave Fairbanks, N8NB, DX Engineering


We received a question from a Ham in Oklahoma about mounting a Cushcraft R8. Although our answer was aimed at the Cushcraft R8, the information can be used for other vertical antennas that are mounted above ground.

Cushcraft recommends that the R8 antenna be mounted at least 10 feet above ground level.

The mast you should use depends on your soil conditions. Here in NorthEast Ohio, I suggest using a post hole digger to make a hole about 12″ in diameter  and about 3 feet deep, and use a 1.5″ water pipe (which is just under 2″ OD) about 5 feet long with threads on one end. Put some gravel in the bottom of the hole for drainage, brace the mounting
pipe with the threaded portion up, and use quick-crete (you pour the dry stuff in the hole, then add water and stir with a stick). It sets up in about 20 minutes – so make sure that mounting pipe is straight up and down so the antenna won’t be leaning. This is pretty much the system I used for my 43-foot ground mount vertical. Using the threads, I could then mount another water pipe to it using a threaded coupler, and then mount the antenna on the extended pipe.

Would I use guy ropes? – YES. And in Oklahoma , a Big YES – you guys get a lot of wind! Any vertical antenna should be guyed. You can use a very light weight rope and make the guy ropes somewhat snug – not real tight. Take a look at the DX Engineering guy rope kits – they may be what you are looking for. I used a four-point guy rope scheme on my 43 foot vertical iwth no problems after 8 years of Ohio wind storms.

DX Engineering OMNI-TILT™ Vertical Antenna Tilt Bases DXE-OMNITILT-2PAnother great option that allows easy up/down for tuning, maintenance ,or in case of severe weather, is to use a tilt base. We suggest the OMNI-TILT Base. There are many tips in the manual about installing and using a Tilt Base, which can be found here. You may decide this is another option to use for the mounting pipe going to the antenna.

– Tom Parkinson, KB8UUZ


If no one is on the repeater and you would like to start up a conversation, simply call the station you wish to talk to. Say “KD8XXX, this is KE8XXX calling.”

Or, if you want to put out a general call to anyone, simply key up and say your call sign.

Don’t be a “kerchunker” on the repeater. A “kerchunker” is someone who keys up the repeater just to hear the repeater courtesy tone.

Don’t call CQ to initiate a conversation on a repeater. Just listen to make certain the repeater is not in use. Then key your microphone, and say your call sign: “KE8XXX” then “listening.” If someone happens to be listening and they want to talk to you, they will respond.

Happy hamming!


ERICO CADWELD ONE SHOT Wire to Ground Rod Clamps GT1-161L

ERICO CADWELD ONE SHOT Wire to Ground Rod Clamps GT1-161L

A “Cadweld One Shot” is ideal for making permanent, reliable connections to your ground rods. It’s a very cool process that is easy to do and will impress even the staunchest members of your radio club!

Using a “One Shot” will provide a very high quality exothermic connection for all of your outdoor ground rod applications. “One Shots” make quick work of ensuring your ground system is the best it can be.

The “One Shot” is a convenient, single-use ceramic mold and welding material connection package. They produce a non-removable, permanent, exothermic connection to a ground rod that will not loosen, corrode or increase in resistance for the life of the installation. They are not clamps, but replace a clamp with a welded connection that thermally fuses the wire to the ground rod. Get you some of THAT!

“One Shots include convenient, single-use (one shot – get it?) ceramic molds that eliminate the need for any type of clamps and/or frames that can loosen or degrade over time. These exothermic connections are ideal for copper-bonded steel, galvanized or stainless steel ground rods.


With all the attention paid to radios and antennas, overall audio quality is often an overlooked (yet vitally important) aspect of Amateur Radio.

bhi audio products harness cutting-edge digital signal processing (DSP) technology to enhance the audio quality of incoming radio signals. By removing the noise, the improved audio makes it much easier to discern distant and weak contacts.

bhi makes three types of Noise Cancellation Products, as we’ll detail below.

bhi audio DSP Speakers and Units DESKTOP

bhi DESKTOP 10-Watt DSP Noise Cancelling Base Station Speaker

The bhi DSPKR and DESKTOP are amplified DSP noise cancelling speakers. These all-in-one packages combine a speaker, 10 watt amplifier, and bhi’s DSP technology to create plug-in-play solutions. Both speakers have manual controls to allow the operator to tailor the sound quality to their liking. The DSPKR is ideal in mobile and portable rigs, while the DESKTOP works perfectly at home in a base station.

For Amateur Radio operators who already have a high-quality external speaker, bhi offers its In-Line DSP units. These standalone boxes install in the audio chain between the radio and the speaker, enhancing the audio from the transceiver before it’s sent to the speaker. The units are housed in attractive, compact cases, and boast intuitive front panel controls for fine-tuning the audio quality. DSP units with dual inputs/outputs are available for radios with stereo capability.

Many popular radio models can also be upgraded with bhi’s DSP PCB modules. The modules install directly into the radio’s audio circuit, and tuck discreetly into the chassis. bhi PCB modules require soldering and installation, which should be performed by a technician who is comfortable working around precision telecommunications equipment.

A wide range of bhi audio accessories like switches, power supplies and extension speakers are available to complement its Noise Cancellation Products.

See bhi Noise Cancelling Products at DXEngineering.com.


Morse Code

CW stands for Continuous Wave. In CW communications, a continuous carrier is transmitted as long as the key contacts are closed. By making and breaking the contacts into specific patterns, characters and entire messages may be sent.

During the earliest days of telegraph, Morse code was the only method for nearly-instant distant communications. Morse code (named for Samuel F. B. Morse) was generated in the clicks made by a sounding bar being attracted to an electromagnet. There was no tone or sound signal present other than a clicking noise. These clicks, and the spaces between them, comprised the code.

The CW tone heard on Amateur Radios today has evolved from the early code first used in 1844. So why, with all the other communication modes available, is CW still used? It’s a multifaceted answer!

For some, CW is just plain fun. The joy of interpreting the sound of Morse code and the challenge of increasing one’s proficiency is very alluring. For DX hunters, code is a robust and reliable form of communication. CW may be understood when voice transmissions fail. This makes it ideal for weak signal DX work. QRP operators capitalize on the ability of CW to “get through.” Other CW users like the historical nature of using a communication method whose development began over 170 years ago. There are many more reasons, we’re sure!

Although many newer devices, like the Unified Microsystems XT-4 Memory Keyer  and the MFJ 464 CW Keyer/Reader Unit, and computer interfaces, like the RigExpert TI-8 Digital Mode and Radio Control Interface, may be used to send and/or receive Morse, many still prefer to do it the old fashioned way- with a standard telegraph key. Using your “fist” and your own ears to generate and decode CW is a source of pride and accomplishment.

Regardless of its age, Morse code (CW) has shown a propensity for longevity and, most likely, will still be in use another 170 years from now!