Tag Archives: VLF

Hamcrafters VLF Converter to be produced in Fall 2018

Many thanks to SWLing Post contributor, Ron, who notes that Hamcrafters appears to be planning a replacement for the Palomar VLF converter.

Here’s the product description:

The Hamcrafters VLF Converter is based on the original Palomar design and converts 10 KHz – 500 KHz to 4.010 to 4.5 MHz. This allows use of your HF Receiver or Transceiver and all its filters, noise blankers, DSP, and memories while tuning the VLF band. Modern HF radios have poor sensitivity in the VLF range (by design). Using this converter with a simple wire antenna will allow receiving of navigational beacons, time signals, and other VLF signals.

The Palomar is well-known among longwave DXers but hasn’t been in production for some time. Indeed, Ron adds, “The last two original Palomars went for $343 and $260 on eBay. Is there a demand? You bet!”

Thanks for the tip, Ron.

Click here to check out the Hamcrafters VLF Converter product page.

Thai cave rescue employed ham-designed 87 kHz transceiver

(Source: Hackaday via bernieS)

Unless you live in a cave, you’ve probably heard a little about the thirteen people — mostly children — trapped in the Tham Luang Nang Non cave in Thailand. What you may have missed, though, is the hacker/ham radio connection. The British Cave Rescue Council (BCRC) was asked for their expert help. [Rick Stanton], [John Volanthen] and [Rob Harper] answered the call. They were equipped with HeyPhones. The HeyPhone is a 17-year-old design from [John Hey, G3TDZ]. Sadly, [G3TDZ] is now a silent key (ham radio parlance for deceased) so he didn’t get to see his design play a role in this high-profile rescue, although it has apparently been a part of many others in the past.

The HeyPhone is actually considered obsolete but is still in service with some teams. The radio uses USB (upper sideband, not universal serial bus) at 87 kHz. The low frequency can penetrate deep into the ground using either induction loop antennas like the older Molephone, or — more commonly — with electrodes injecting RF energy directly into the ground.

You can find a very detailed article about the radio from 2001 if you want more details. The system is somewhat dated, but apparently works well and that’s what counts.[…]

Click here to read the full article at Hackaday.

Grimeton Radio / SAQ Transmission on July 1st, 2018

Many thanks to SWLing Post contributor, Evandro Stanger, who writes:

Good news. Grimeton Radio will be on air again on July, 1. See the link below:

(Source: The Alexander Association)

Grimeton Radio / SAQ Transmission on July 1st, 2018.

The annual transmission on “Alexanderson Day” with the Alexanderson alternator on VLF 17.2 kHz with the call SAQ will take place Sunday, July 1st, 2018.

This year, three transmissions are scheduled as follows:

1. Startup of tuning at 10:15 (08:15 UTC) with a transmission of a message at 10:45 (08:45 UTC).
2. Startup of tuning at 12:15 (10:15 UTC) with a transmission of a message at 12:45 (10:45 UTC)
3. Startup of tuning at 14:15 (12:15 UTC) with a transmission of a message at 14:45 (12:45 UTC)

All three transmission events will be broadcasted live on our YouTube Channel.

Amateur Radio Station with the call “SK6SAQ” will be QRV on the following frequencies:
– 7.035 kHz CW or
– 14.035 kHz CW or
– 3.755 kHz SSB

Two stations will be on the air most of the time.

QSL-reports to SAQ and SK6SAQ are kindly received via:
– E-mail to: info@alexander.n.se
– or via: SM bureau
– or direct by mail to:

Alexander – Grimeton Veteranradios Vaenner
Radiostationen
Grimeton 72
SE-432 98 GRIMETON
S W E D E N

The station will be open to visitors between 10.00 am to 4.00 pm.

WELCOME!

World Heritage Grimeton Radio station and The Alexander Association

For further details, se grimeton.org or alexander.n.se

Excellent news!  Thanks for the tip, Evandro!

Ron discovers a new VLF converter

Many thanks to SWLing Post contributor, Ron, who writes:

A firm in the UK is now offering new VLF converters in built, ready to go form or in kit form.

Coverage is 10-500 khz full LW band or 0.1-100 kHz ELF band.

Your choice of stock or SO239, BNC or RCA connectors for antenna input and converter output.

Powered by a nine volt battery.

In addition a special 630m version is available tuned for max performance on 475 kHz in the middle of the 630m band.

Click here to view on eBay.

Thanks for the tip, Ron! Based on the photos, the construction looks to be of very good quality. There are so few VLF converters on the market–please share your review when you’ve had a chance to evaluate it!