Author Archives: Thomas

Bill tweaks his AM loop antenna for optimal mediumwave performance

Many thanks to SWLing Post contributor, Bill Hemphill (WD9EQD), who writes with the following update to his previous post:

As you may remember, back in May, I picked up a beautiful home-made loop antenna. It was 25 inches on a side with 23 turns of wire. My initial testing showed that it would tune from 280 kHz to 880 kHz. While I was familiar with loop antennas, I had never tried using one.

My initial tests were disappointing. So I spent some time on the internet reviewing AM loop antenna designs. I came across a reference to an AM Loop Antenna Calculator by Bruce Carter:

http://www.earmark.net/gesr/loop/umr_emc_calc.htm

I first measured the tuning capacitor and found that it tuned from 25 to 400 pF. Entering the data into the calculator:

This matches closely to what I was experiencing.

I then proceeded to calculate various Number of Turns to see the effect on tuning range. My goal was to tune the entire AM broadcast band.

I settled on ten turns which gives the following from the calculator:

Perfect. I removed 13 turns (which left ten turns) and then added a two turn secondary loop which would be connected to the radio. The results were fantastic.

I have created three short videos showing the difference between using the Tecsun S-8800 without the loop on a weak station and then using it with the loop.

[Note: If you’re viewing this post via our email newsletter you might need to view this post via a web browser to see the following embedded videos.]

Without the loop

With Loop

As you can hear, a very noticeable difference.

[After making these videos] I tested the of reception of 1510 kHz on the Panasonic RF-2200:

The results are amazing.

I have logged three stations on one frequency. Just peak the one station, then tune the loop and peak the second, then turn the loop some more and peak a third station.

I’m having a lot of fun with the loop. When it gets a little cooler, I plan to take it to the park where there is zero noise and really put it through its paces.

Excellent job, Bill! You’ve proven that doing a little research and making small adjustments to an antenna design can yield impressive results! Thank you for sharing!

CountyComm GP5-SSB limited production overrun sale

Paul seeks help identifying BRT English service program theme

AFRTS: Thousands of hours of Roger Carroll shows now online

White House petition to maintain NIST funding of WWV time stations

20 Replies

Many thanks to SWLing Post contributor, Tom Kelly, who shares the following:

I recently read your article concerning the proposed shutdown of the NIST stations WWV/WWVH.

To that end, I have gone ahead and created a Whitehouse petition to see if this decision can be reversed:

https://petitions.whitehouse.gov/petition/maintain-funding-nist-stations-wwv-wwvh

Would there be any way you could perhaps post the link to this so that fellow members of the SWLing Post could sign it? I believe the more folks we have sign the better chance we have of maintaining the radio stations we have all come to rely upon.

Thanks, Tom, for launching this petition–I had planned to do so this morning and am thankful you beat me to it.

SWLing Post readers: please take a moment to sign this petition. It requires only a few seconds to complete and you need only to submit your name and email address. This is an official petition instrument of the White House and, as such, can actually lead to a response and potential review. Please spread the word throughout your radio communities!

Click here to sign.

Please spread the word!

Richard’s 25 MHz WWV QSL

3 Replies

Many thanks to SWLing Post contributor, Richard Schreiber (KE7KRF), who writes:

The NIST article about WWVH was very interesting and informative.

It reminded me that lately WWV’s broadcast on 25 MHz has been received from time to time here in southern Arizona. I emailed a report and recording to NIST in late June and received a QSL (images above).

I don’t know the status of the 25 MHz frequency. In 2017 NIST was soliciting reports but I haven’t found any current details on the web.

Thanks for sharing this, Richard. I’m under the impression that the 25 MHz frequency is still in use, though I may be wrong. This is also a great reminder–many don’t realize–that WWV does issue QSL cards!

Of course, as we’ve mentioned in a previous post, if the FY2019 presidential budget proposal is accepted/approved, WWV will be no more.

August 2018 Rockwork Ocean Cliff DXpedition most distant AM-DX

2 Replies

Many thanks to SWLing Post contributor, Gary DeBock, who shares this note from the recent Rockwork Ocean Cliff DXpedition:

The most distant AM-DX received during the August 2018 Rockwork Ocean Cliff DXpedition was 558-6WA in Wagin, Western Australia, received during the last session (9 out of 9) at 1252 on August 9th. At 9,154 miles (14,732 km), the ABC “Nightlife” program content was matched to the related ABC website Podcast. The co-channel music is from 558-Radio Fiji One This was received on an XHDATA D-808 portable boosted by a 17″ FSL antenna: