Monthly Archives: December 2014

Some new DX!

Finally worked Japan yesterday on 10m PSK31. I almost made a Phone contact as well but the station faded out before I could break the pile-up. Today managed to snag a new PSK31 station in the South Cook Islands as well. I saw him on the waterfall yesterday but could not work him although he had a strong signal. I took a chance today at about the same time and he popped up again. Glad to make these contacts as Asia and Oceania were sorely missing from my QSO list.

A little diversion

I have been working quite a bit on learning and improving my HF operating skills as well as building some antennas for portable use. I am still working on the buddistick but have not been able to get it outside for testing. It is a bit to windy outside today to set it up as I have not worked out the guy wire scheme yet. I decided to try and finish a little project I had started a while back to put together a scanner for the public service band frequencies here in Brownsville. I have two USB dongles with the 820T tuner chip in them and wanted to set them up to run Unitrunker software. I had tried this once before with no success.

My original plan was to do a three way split from the discone antenna outside to allow me to use one line for the panadapter dongle and the other two for Unitrunker. The wiring for this was a little messy so I decided to try and build a 1/4 wave vertical for 865Mhz. This turned out to be easy as the elements are about 3-1/4″ long. I soldered heavy gauge wire to a chassis mount SO-259 connector, one at each mounting hole for the radials and One to the center terminal. The radials are bend down by about 45 degrees to raise the feed point impedance. I am using 75 Ohm coax for a feedline with a SO-259 to F-connector adapter. Only issue building this is it takes some time to heat up the connector flange to get a nice solder joint.

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I tested this little antenna using SDR# and it was picking up the signals quite well. I was surprised to even get a strong signal at 162.55 MHz weather radio frequency. I may have to try this out on the air bands as well just for grins. I had much better luck setting up Unitrunker this time. I think I was using the wrong control frequency before. 858.075 MHz did the trick this time. I am going to try a different configuration that uses a SDR# plug-in and see if it provides any better functionality. I think it will allow me to download the available talkgroups from radioreference.com so I can tell who is speaking.

First impressions of the “MINI60” Antenna Analyzer

I mentioned in a previous post that I had ordered a “MINI60” antenna analyzer on Ebay. Well it finally arrived today and not a moment to soon as I started building a homebrew Buddistick. There are quite a few negatives floating around the internet but I took a chance anyway. These units are Chinese made clones of the Sark100 originally designed and built by EA4FB. The unit arrived wrapped in bubble wrap in a small box with nothing else. These are notorious for not having a manual or documentation. It looks pretty sturdy as it uses a metal case. It is about the size of a pack of cigarettes and has a SO-239 connector on the end. I have plugged the unit into a USB charger and it indicates it is charging. I’ll let it charge overnight and see if the light turns green.

I did connect it to a laptop and it found the drivers with no issues on my Windows 7 machine. It appears as COM4 on my machine. There is a command line program originally for the Sark100 that seems to work well in scanning across a range of frequencies and dumping the data to a comma delimited file. The Z-Plots program can then be used to plotĀ  a variety of variables such as SWR, Zo, Rs, Xs etc. I did a quick test with an oscilloscope to very the output frequency as this was one of the issues discussed on the internet. The waveform checked out ok at 14.1 Mhz, I measured the end fed antenna and got back reasonable looking results. I’ll be posting more on this device in the next few days.

The Wait is over…

Finally received the Yaesu FT-817ND and the Z817 autotuner. Really small rig! I am really impressed with the size and weight. I installed a high capacity NiMH battery pack and am starting to condition it per W4RT’s instructions. No contacts yet with it but did start working on the antennas now that I am on Christmas/New Years vacation. My goal is to pack the whole system in a portable case for field work.

Waiting….

Parts for my vacation projects are starting to trickle in. Santa is scheduled on Friday with the FT-817ND and I have pretty much decided to work with an end-fed antenna and build a buddistick to try out first. I have also been watching carefully for the Mini60 antenna analyzer. Downloaded some files that should help with its use. Really looking forward to a playing with a portable QRP station soon.

Setting up a portable station for Christmas

Treating myself to an early Christmas this year by buying some equipment to play around with. I have a Yaesu FT-817ND QRP rig on the way and a bunch of parts to make antennas with. I am looking to setup a portable QRP station that I can use on camping trips and field day. Will likely be taking the shack into the backyard in the coming weeks (if the weather permits).

The antennas I am looking to build are another end-fed antenna with a 9:1 unun as well as a buddipole and buddistick. These are fairly easy to make based on some plans I found on the internet. I ordered some connectors off the internet and will make a Radio Shack / Home Depot run this weekend for the other parts. I’ll test these out with the radio when it comes in and see which one performs the best and is also portable.

I am also planning to build some small verticals for reception on 855Mhz and see if I can get a trunking scanner working with the RTL-SDR dongles.

I have also taken a chance with a low cost, Chinese antenna analyzer based on the Sark100 design. This one is labeled as “Mini60” on Ebay. If all goes well it should help tune the homebrew antennas. I’ll post a detailed review once I get it in.

All this should keep me out of trouble over a long Christmas / New Years holiday!

Upgraded to Extra

Forgot to mention earlier that I took my Extra class license test on November 22nd and passed it! The FCC database was updated about a week later with my upgrade.

AFCI and HF signals

About the time I set up my station, I updated and repaired some electrical issues around the house. Part of this was for the radio setup. I added some ground rods and bonded them to the main house ground rod. I have one rod outside my station and the other is over by the where the antenna is installed.

Inside the house, I had to replace a GFCI breaker that was faulty on my load center. This breaker controlled by outside outlets as well as the bathroom outlets. While I was at it I had the electrician add a second one to cover some outlets near the kitchen sink. All was well for a while.

I started noticing that the GFCI would trip on both new breakers. I suspected the radio but didn’t see a correlation until I started using PSK31 on 20m. I started digging around some more and found that what was installed were Eaton AFCI breakers. These are well know to be susceptible to be tripped by HF signals in the 20m to 12m range. So using 10m everything was ok. When I tried 20m PSK31 transmission the breakers tripped almost immediately. Go figure….

So my plan now is to have the electrician come back in and replace the AFCI breakers with standard ones. Then I have to replace about five standard outlets with Leviton GFCI types. That should so the trick.

Working with HF Digital

I finally configured HRD for PSK31 and have now been making most of my contacts in this mode. Amazing how you can make DX contacts with 30W! Saw some Contestia signals on the waterfall today but didn’t try and make any contacts.