Wednesday, August 3, 2022

POTA activation with TR-35 and 9V battery

Years ago - pre-POTA and pre-lithium - some intrepid QRPer (a W3-lander) decided to see how many states he could work with a single 9V alkaline battery during Sweepstakes. I don't remember his results but his radio was a new-at-the time Norcal 40A.

These days, any weekend POTA activation can serve as a test platform for this and other absurdities.

I decided to see if a 9V alkaline battery could power my TR-35 long enough to make the 10 contacts required for a valid POTA activation. The TR-35 draws 90-100 mA on receive. Transmit current (with 9V DC in) is 700mA and that results in an RF output of about 1 watt on 20m and 2.5 watts on 40m.

Monday, August 1, 2022

Video: sBitx showing integrated FT8 operation

Ashhar VU2ESE demonstrates the built-in FT8 functionality of the new sBitx. I'm not really much of an FT8 operator but I do appreciate the innovation involved here.

From Ashhar:

The "Development Edition" is a bit of a misnomer. It doesn't mean that there are big bugs. Rather, this version is all large PCB and configured with all the tools needed for builders and software hacks to poke and see and code. 

Unlike the closed software (like the Xeigui SDRs), the bugs will be welcome and fixed pronto. The update is trivially easy. You just have to put the radio online (wifi or ethernet) and type "git pull" to pull the latest version from the repository. No need to learn to program.

An sBitx is now on its way to my humble shack.



Thursday, July 28, 2022

A groundbreaking new radio from VU2ESE

I've been following the progress of a very interesting new radio being developed by Ashhar Farhan VU2ESE.

His newest creation, the sBitx, is the first radio to integrate digital modes like FT8 into the radio as part of its native functionality, along with SSB and CW. I believe we will see this digi-mode integration become more and more common in the future, eventually being fully embraced by the Big Manufacturers.

As of yesterday, the sBitx is available as a boards-only kit ($270) or as a fully tested ($499) 10-80m transceiver. And it's not QRP - the sBitx has an output of 40 watts on 80m, decreasing to six watts on 10 meters.

A Raspberry Pi 4 operates the radio and encodes/decodes FT8, PSK31 and RTTY, displaying the text on the built-in 7-inch screen. FT8 operation is selectable as either manual or semi-automatic and stations are worked (or CQ's called) with commands issued via the touch screen or a USB mouse plugged into the radio.

Saturday, July 16, 2022

Status so far, from Ecuador

After spending 6 days in Quito, we arrived at our Cuenca QTH four days ago. We are staying at an Airbnb just outside the historic district of this amazing city, and you know what that means - QRN.

The Airbnb is a fully furnished two-bedroom apartment, in a 3-story building, in a residential area and we're on the top floor with a large balcony that looks to the northeast. Fortunately, there is also a gap to the northeast in the mountains that surround us. Propagation on 15m has been fantastic and I'm getting into W1, 2, 3 and Europe, no problemo, on 15m.

Sunday, July 10, 2022

POTA Fail: I took a taxi to Cotopaxi

It coulda been awesome.

Everything was planned and all the parts had been tested on numerous stateside POTA ops. My driver, Santiago, was totally into it and eager to see Morse Code in action with his car as my "estación".

Batteries were charged, for both camera and IC-705. Lammas grazed in the fields along the highway to the park.

But the weather was against us. Solid fog and light rain limited the visibility to a few hundred meters, if that. Cotopaxi could not be seen at all and park officials were not allowing anyone to proceed beyond the parking area.

Hikers, bicyclists and would-be climbers with crampons and ropes were sitting, waiting.....

But I had a back-up plan since photography was out - I'd just activate from the parking lot. Done it before in FL and TX.

Santiago helped me by maneuvering his taxi into an area surrounded by grass so I could lay out a radial without fear of someone driving (and parking) on it. He attached the mag-mount to his taxi, I connected the radio bits and pieces.