Monthly Archives: April 2016

Recieving WSPR

Our local radio club, C.H.A.R.R.O., held its second monthly seminar today at the CAF museum at the Brownsville Airport. We had two great presentations today. Dick, WB5B, gave us some info on WSPR and on how it can be used to monitor propagation using weak signals. Clifford, N5CEY, showed us how to make stealth VHF & UHF slot antennas using old satellite dishes. He gave three of them away as door prizes! Nice.

The WSPR presentation got me interested in setting up at least receive only while I am away for the next couple of weeks on business. I setup my SDRplay through HDSDR to route the receiver output through a virtual audio cable to the WSPR application. I didn’t know if any of this was working as I got no signals on 30m. I switched to 20m and I have started decoding signals. I’ll keep this running and check wsprnet while I am away and see how its doing.

Worked the local VHF Digital Net

W8WKE runs a Wednesday night digital net at 6pm on our local repeater system. I had been wanting to try it for sometime but did not have an interface for my VHF rig. Clifford, N5CEY, hooked me up with one of his Easy Digi USB interfaces for my Yaesu FT-2900R rig. I set up Fldigi on my radio laptop and set it all up to the rig. The net uses MT63-2000L protocol. When the net started I was able to start decoding the transmission without any issues. Unfortunately, I could not transmit. The Interface handles the PTT with the rig and appears to the PC as a serial COM port. I had both DTR and RTS enabled but nothing worked. Then I noticed a small enable check box above the COM setting. I enabled it and the transmit started working without a hitch. I have played with HF modes on DM780 so I need to now learn Fldigi. When I get back from my next business trip I plan to hook up the VHF antenna to the IC-7100 and try and work it from there with HRD. Working this net was a lot of fun and I am looking forward to trying it again.

Great DX SSB contact with IC-7100

I have not been on the radio much since I setup the new IC-7100. There is still a bunch of stuff I need to setup on it (DStar, VHF/UHF etc). One thing this new rig has had numerous negative comments on is a rather anemic SSB power output. My new rig has the latest firmware from ICOM that supposedly corrects the issue.I have not seen many comments from IC-7100 owners about the effectiveness of the fix. This morning I had a combination of conditions that lead me to believe that the rig is A-OK.

Tuning around today on 20m I came across a weak SSB signal from a station in Indonesia. This is a desirable contact for me as I do not have that country in the log for DXCC. Propagation has not been good. with a solar flux index of 86 and a sunspot number of 65 and K=2. Here is the prediction map for the time of the contact:

2016-04-27_12-08-24

The map shows that a path was open to that region from South Texas.

I was having trouble copying the station but did make a call a couple of times to no effect. I switched to the FT-450 and had a similar result. I noticed that the 7100 did slightly better on receive and the DSP controls are a lot easier to access. I switched back to the 7100 and found the receive was slightly better to my ear. I called again after hearing his QRZ and was able to hear him copy my signal with a 57 report. We had a brief exchange and completed the QSO. Given the combination of band conditions, and switching between rigs I believe the rig is working SSB reliably. I know this is somewhat anecdotal but lacking a peak reading meter this is the best proof I have.

Great ManPack Reference

W7KI has a great site on building a ManPack for portable operations. Lots of good advice on the build. I would like to build one of these up soon for my FT-817ND.

Broadband-HamNET

I just got back from a business trip and decided to spend this afternoon dusting off some old Linksys routers to setup Broadband-HamNET firmware on them. I had to make a quick run to Home Depot for a couple of Ethernet patch cables but lucky I had everything else on-hand. I followed the instructions at broadband-hamnet.org and the setup was quick and uneventful. The routers I am using are Linksys WRT54GS version 1. I had played around sometime back with DD-WRT and found that this firmware was still on them. The new firmware installed without a problem. Once installed you just have to setup your call sign and new password. Just be sure to disable your current LAN when doing the setup so your PC doesn’t get confused. I did this on both routers and had them each connected to separate computers. At this point I can’t do much else but I was able to ping across the wireless link.

What I have now is basically a short range two node wireless network. Each node finds any others in range automatically and creates a mesh network. Imagine the first two computers on the internet…that is essentially what I have here now. A wireless network with no content. So to make this interesting I am going to install VMware Player which will allow me to run virtual machines. I will then install Linux as one of the virtual machines which I will configure to provide some familiar internet services such as web pages, FTP, IRC etc. This will allow all mesh nodes to access these services over the wireless link.

Longer range (no pun intended) plans are to get these mounted outside and try some distance link tests. Interesting way to get involved with the microwave portion of the ham bands.

 

Never to Early to Start Preparing for Field Day

The title says it all.

I had a great first Field Day last year running as a single op battery power station and made close to 50 contacts on 5W SSB from my dad’s house in Mercedes. I plan to work the same mode as well as add some digital PSK31 to the mix. The main thing is to make sure I can run a laptop on solar power during the contest. The stress tests I am running should all help me decide what I can do for Field Day this year.

Plans for Solar Powered Station Stress Test

I have just acquired an LDG Z-11proII autotuner. This is a low power autotuner made for portable use. I am planning a full power stress test of my solar powered portable station with this. My plan is to deploy the 30 foot vertical end fed wire antenna using the portable fiberglass mast and use the FT-817ND with the 45W amplifier to run at full portable power. I will also run a laptop by powering through its 12V travel adapter. My goal here is to see what my worst case power consumption would be using this configuration. Hopefully I can also try some digital with the FT-817ND for the first time as well. This should be good practice for Field Day coming up in June.

And Now for Something Completely Different…

I have discovered the ham activities with High Speed Multimedia (HSMM) and am very interested in playing with this. I have ordered the new ARRL book on the subject and meanwhile have been scouring the internet for more info.It turns out that I have two of the Linksys routers needed for this gathering dust in my “obsolete” box. In my case these are Linksys WRT54GS v1 routers.I also have an old wireless access point that I can bring into service. My thinking is to try and get a couple of nodes working here at the QTH to test the system out. Stock antennas should be good to about a 300ft range. If I can get this all to work then I can look at getting a longer range, portable system in place and seeing if I can find another local ham who would be interested in playing with this technology. I like the idea of working in the microwave range as there are a lot of fun antenna projects that can be brought to bear.This may also have some application in EMCOMM which would be interesting to explore as well.

So many new things to try in this hobby!

Update on Toroid Coupling

I spent some time yesterday working with the toroid coupling. This time I used #18 insulated wire on the FT140-43 toroid. It still worked out to 4 turns being the best match on 20m. The SWR worked out to 1.02 on this band. I was getting SWR of 1.2 on both 17m and 20m. The smaller gauge wire is much easier to deal with. Also found that I can move the toroid to just against my vertical PVC support and hold it in place with the Velcro tying the feedline to the PVC. May be a solution for field work after all but I’d need to test this on the 12m and 10m bands as well. During testing I managed two 5W SSB contacts from inside the shack with good signals reports. One was in Georgia and the other in Cuba.

Testing Toroid Magnetic Loop Coupling

I am planning on feeding the 40m NVIS Magnetic loop antenna with a Toroid configured as a transformer. I ordered and received some FT140-43 and FT240-43 toroids off of eBay this week and decided to try and match my existing loop as a test. The trick is to determine the proper number of wire turns to get a good match. For me this was trial and error. I started with about 8 turns of #14 insulated solid wire on the small FT140-43 core. I’d run a sweep with the antenna analyzer and remove turns until the SWR dropped to close to 1:1. For this configuration it worked out to 4 turns. Here is what is looks like as I tested it:

Photo Apr 09, 5 11 15 PMPhoto Apr 09, 5 47 30 PM

Here are the SWR plots. First up is the Faraday coax loop I have been using on 20m:

loop20mfaraday Custom

Here is the plot with the toroid also on 20m:

loop20mtoroidsolid4 Custom

Very Reasonable agreement.

Here are the SWR plots for 17 & 15m:

loop17mtoroidsolid Customloop15mtoroidsolid Custom

The good news is this works!

Given the current design of my portable mag loop I may continue to use the coax coupling loop. I would have to change the way the loop is held up to accommodate the toroid. This will not be a problem with the 40m loop as I will feed it on the bottom as the capacitor section will be on the top. I’ll likely also change to an easier to work with wire gauge to get the windings tighter on the core. That #14 wire is pretty stiff and hard to work with. I tried some stranded speaker wire and it is hard to get it to stay put. Once I get some better wire I’ll try the larger core and see if there are any differences. Meanwhile, I have gathered up the rest of the parts for the 40m loop and hope to start building it yet this weekend.