Friday, February 1, 2019

QRPLabs clock built; U3S rebuilt

A lovely pair
As a geographical bachelor for the past week, I've had time to tinker and melt a bit of solder.

My 6-band Ultimate 3S has been a solid performer but I never was happy with my level of construction - the interior was an entanglement of wiring, using whatever I had on hand at the time for the interconnections.

Yesterday, I stripped it down to brass tacks and re-did the whole shebang, using ribbon cables for the interior wiring.

I also added the updated firmware, going from V10 to V12. This adds a few capabilities to the U3S that don't apply to my use of it at the moment but may if/when I build the 10W amp kit designed for this kit.

Not likely, given last night's performance on 40m WSPR with 100 mW:

While I had the workbench populated with all the necessities I also assembled the clock kit from QRPLabs.

This is a GPS-controlled clock with a variety of options for configuring the display. I simply wanted a simultaneous display of local time and UTC, mainly for logging purposes.

I also wanted the GPS receiver to be inside the case so that the whole thing was self-contained (my U3S is also GPS-controlled but that receiver is separate from the main unit). Of course the small patch antenna couldn't be inside the metal case so I drilled a small hole in the top of the case for connection of a short piece of coax, then epoxied the antenna in place.

The internal GPS receiver has no problem locking onto satellites within about 2 minutes of a cold start.


  1. I have both the 6-band U3S and the clock kit, along with a GPS board, waiting on my workbench, still in their parts bags. The cabinets, which are supposed to ship from China, were rejected at the port of entry due to bad export papers, were returned to China, and are being re-shipped. The PCB boards and parts, which came from Istanbul, were here in less than a couple of weeks. The cabinets are now in their 3rd month. I mean to ask QRPlabs if they are aware of what is going on with the shipments from China. Seems unusual. I wonder if it has anything to do with the recent tariff wars?


    -- Dave, N8SBE

    1. My electronic parts from Turkey arrived in exactly 21 days; the cases from China took two months - normal for surface mail from there. I ended up operating the U3S (in single band config) without the case for several weeks as a WSPR transmitter on 40 meters. I'm sure you'll like these kits once you get them built. The U3S in particular is quite versatile.

      73 - John AE5X