Fort Worth Nature Centre and Refuge

While in Fort Worth for the FTWSO concert series I looked for a place to go exploring on the Sunday Morning. Searching the internet I came across the Fort Worth Nature Center and refuge http://www.fwnaturecenter.org/ which had some creatures, scenic drives and trails. It is off the Jacksboro highway, NW of downtown Fort Worth.

Having paid my $5 admission i made straight for the Visitor centre. I did two walks centred there Caprock at 0.5 miles and Limestone Ledge at 0.2 miles. They also have two owls in the refuge, both hit by cars, a greater horned owl and a barred owl

I then drove to the boardwalk which is supposed to be a walk over the marshes over Lake Worth. Unfortunately it being August in Texas it was completely dry with no water in sight

The car park (EM12GU) was quite empty so a wire was thrown into a tree and the KX3 activated. A couple of stations were worked in the KS QSO party on 20m 1548 NoU/ALL 1549 W0U/SHA but the bands were quite dead and it was way too hot to operate from a car for any length of time.

The final visit was to the road named "Buffalo drive". Unlike earlier, when driving to the visitor center on this visit there were plenty of brown buffalos and also the rarer white ones

 By now it was noon and time to head for lunch and then to Bass hall

Fort Worth Symphony "From Russia with Love" concerts

While listening to the local classic FM station on 101.1MHz  on the way to work last Monday I heard adverts for a three concert series this weekend entitled "From Russia with Love" by the Fort Worth Symphony Orchestra. They normally do a series of three concerts on a theme as an intro to the concert season; this year the three were dedicated to the memory of Van Cliburn who died earlier this year

A total of Six pieces all by Russian composers with three piano pieces played by Cliburn 2013 medalists and three russian Symphonies; not to be missed, so tickets were purchased. $18 each for the 3 concerts in the centre of the lower mezamine

I drove the 47 miles to Fort Worth direct from work on friday evening and even had enough time for banana spring rolls desert in PF Chang 3 blocks from the concert hall in the usual pre-concert ritual.

Friday night started with a eulogy to Van cliburn which was inaudible due to the bad PA audio (still) in the Bass Hall  The first half  had Beatrice Rana, the 2013 Silver medalist (wearing a silver sparkly dress as a reminder?) playing Tchaikovsky’s Piano Concerto No. 1. . The first movement was a bit slow and she was overpowered by the orchestra at times but very enjoyable. Her encore was the Schumann-Liszt composition, Widmung. The second half was the FTWSO playing Tchaikovsky’s Symphony No. 4. Fort worth star telegram review. One other feature  of the Bass hall is a Starbucks across the road in the Barnes and Noble bookshop which serves coffee until midnight, you dont get that after theatre in Malvern!

Saturday night had Italian pianist Alessandro Deljavan a 2013 semi finalist (rumoured not to have progressed further because of facial/body contortions while playing!) playing Rachmaninoff’s Piano Concerto No. 2  in the first half which was a very different interpretation than normally heard . . His encore was the Chopin’s B minor Etude which was stunning. The second half was the FTWSO playing Tchaikovsky’s Symphony No. 5 underwhelmingly.  Fort worth star telegram review.

Sunday afternoon  had Sean Chen, the 2013 Third place playing Rachmaninoff’s Piano Concerto No. 3. in the first half (same piece he played in the Cliburn final 11 weeks previously).  His encore was a mystery until afterwards due to the awful pa system in the Bass Hall (just as bad as during the Cliburn competition)."Chen turned to two violinists and two cellists in the symphony and asked each of them to play a note of their choice. He then returned to his piano bench and did about three minutes of improvisation on those four notes."  A first for Bass hall!. The second half the FTWSO playing Tchaikovsky’s Symphony No. 6 (Pathetique) which was well played but the most memorable part was the raspy sounds produced by the horns   Fort worth star telegram review.

The east angel on the front of the Bass Hall.  They were hewn from solid marble in California then shipped to Texas. The head fell off the first one to arrive and had to be remade from scratch and reshipped

53 mile drive back to the apartment; an enjoyable weekend!

RPI R820T RTL2832 SDR Server

As a way of keeping an eye on conditions i have taken to installing the rtlsdr dongle out on the balcony hooked up to a 50MHz dipole and using the Dell laptop as a display sitting on a chair. The weather in Dallas has returned to Summer normal about a week ago after having a week of mainly rain so 100degrees F plus is now the normal. Too hot to sit out on the balcony and look at the bands, There had to be a better solution

Searching the Internet I came across a page by EB1HBK "Receptor SDR remoto con Raspberry Pi"
on how to set up a raspberry pi as an RTLSDR remote server. The pages are in Spanish but despite having had my Spanish corrupted by Mexican Spanish I managed to work it all out and get it up and running

The RPI sits out on the balcony with RTL-SDR and power supplied through the USB hub from a 5V 4A PSU acting as a server. It is connected  via an ethernet cable to the router. The server can be started remotely using SSH through the Putty programme

The laptop in the airconditioned apartment runs sdrsharp. In SDR Sharp the device is set to "RTL-SDR TCP" with the IP of the RPI (192.168.1.64) and the default port of 1234

Infrared decoder Project

As is quite common nowdays , our TV does not have speakers, the received audio has to be sent to an external audio Amplifier. When playing back video files on the PC it also needs to send audio to the same amplifier resulting in the need to rearrange cables behind the TV when wanting to swap over. There had to be a solution

I took a look on ebay.com whereas HDMI switch boxes were available boxes to switch Left and Right Audio on Phono jacks were rare and expensive

I wondered if I could use the TV remote and build a decoder to switch between the 2 sources. As I had a couple of Arduino Unos, bought when on offer at radioshack, they seemed an ideal candidate

Searching the internet I came across some web pages at adafruit.com that would be useful. A walk to radioshack (I am now only 300 yards from one now) procured the necessary IR detector.It was hooked up to the arduino and the software loaded from http://learn.adafruit.com/ir-sensor/reading-ir-commands. I pointed the IR remote that came with my RTL2832 TV dongle at the decoder and saw the pulse codes. The software allows the pulse codes to be recorded.  and placed in the file you can use as a reference to switch arduino outputs. I choose the red button to choose TV as source and Green button for Computer.

Next a 6V DPDT relay was found in the junk box and mounted on an arduino protoshield board. The relay was switched with a 2N7000 FET from the arduino output. Two LEDs were added in software and hardware to show the audio source. The whole assembly was mounted in a Diecast box with a hole filed out in the front panel to allow the IR detector to be mounted.

The arrangement worked fine but I kept losing the RTL2832 controller, which was small. I decided to use two of the spare buttons on the existing IR controller, Not hard, all I had to do was record the pattern and put it in the lookup file

A useful afternoons work!

KX3 Noise reduction modification

Elecraft finally published details of the mod to reduce the noise heard in the receiver when turning the tuning knob, especially on 6m The document is at. http://www.elecraft.com/manual/KX3%20Tuning%20Noise%20Mod%20rev%20B3.pdf
Tonight I did the modification that basically cut 3 pins off the KXFL3 module and took 10 minutes to complete. The fix was very good and I now hear no noise on 6m or 10m, even in a low noise location

Single tube super-regen kit radio

Having Bolted together numerous Elecraft products I decided i wanted to build a radio with a soldering iron. While I debated about getting a K2, I looked for some cheaper options, preferably olde worlde!

On ebay I came across a single tube regen kit at http://www.xtalman.com/kits.html. It is also sold on ebay. Everything is supplied except the batteries for $65

The kit took around 6 days to complete. The coil former is a paper tube that needs 3 coats of varnish which took 3 days. When this is dry the windings are put on the coil former and the coil given 2 coats of varnish. The circuit is built on a wooden baseboard which also needed two coats of varnish. The following shows the major components mounted on the board

It did not take long to assemble as it is all direct point to point wiring. The receiver is battery powered. The heater supply is two D cells for 3V at ~30mA . The Anode supply is Five 9V batteries bolted together for 45V

I hooked it up to a 60' wire and the ground was the mains ground. In daylight i could hear 3 local stations. In the evening I could hear 11 stations in 3 countries. Using a regenerative receiver takes some getting used to, but the technique soon came back!

R820T RTL2832 SDR Dongle under Android

Surfing the web I came across an article on the Ham Radio Science page http://www.hamradioscience.com/android-meets-the-rtl2832u/  with an app to use the SDR dongle I had previously used under windows and Ubuntu on my Nexus 7 Tablet under Android. The app is called SDR Touch, the authors web site is at http://sdr.martinmarinov.info/ . All I needed was  the appropriate OTG micro USB cable.

Firstly I downloaded and installed the demo version of the software and driver from the web site. I found my OTG cable that I bought after the Nexus 7 but never used. I plugged the dongle into the micro usb port via the cable and launched the App. It failed to find the receiver. I then noticed that the blue light had not illuminated on the receiver. Very Strange!

A trip was made to the local emporium (Frys) and a $5 OTG cable was purchased. Interestingly the sales lady asked what tablet was for. When I said the Nexus she said it would work, if I had a Galaxy it would not. Obviously all OTG cables are not created equal!

Now when I plugged the receiver in it lit up, the Tablet found it and I had a spectrum display. Tuning to the local classics station it demodulated nicely.

 The demo version has restricted features (no direct frequency entry, only 30secs of spectrum display, no waterfall display and  no presets) but I was so impressed with what I had seen so far that I went to the app store and paid my $9.99 to upgrade from the Demo to the Full Version of the software. This was easily installed and the following shows spectrum, waterfall and presets:-

I did run the driver app on its own and it did show communication with the correct tuner chip

Very useful discovery.

Printing money legally

While staying in a hotel in Plano a few weeks ago, I was browsing the tourist leaflets in the lobby and was surprised to come across one for  the US Bureau of printing and engraving in Blue Mound, just North of Fort Worth. Until that point I thought all money was printed in Washington DC. The interesting point was that they did tours. http://www.moneyfactory.gov/tours/fortworthtxtours.html (whoever named the web site had a sense of humour!)

So Friday morning after the morning rush hour finished I drove over there. It took just over an hour, the biggest problem being the roadworks on I820 on the north side of Fort Worth

There is a separate entrance for the tour with security checks (no cameras, computers, phones, backpacks, Mace, explosives or any other electronic sevices). You then board a bus which takes you to the main building. There is a museum on the ground floor which was fascinating. For instance I discovered why the south got known as Dixieland. The Citizens Bank of Louisiana, a predecessor of J.P. Morgan Chase and Co., issued its own notes before the Civil War with the word "Dix", ten in French, on one side of the note. The region got know as the "land of Dix" which got shortened to Dixieland

On the first floor is a film theatre where there is a film showing you the printing process. There is also the entrance to the walkways so you can go on an audio book guided tour and see the printing machines in action. (until last October a guide did the tour but that stopped with Federal budget cuts!). Due to printing notes involving 3 printing presses and drying time being a couple of days it takes around 2 weeks from the paper input to the printed notes being given to the Feds. I also discovered there is a Damaged currency unit that redeems partially destroyed or badly damaged currency 

Radio Goodies Arrive

The USPS had a busy day delivering today!

The new side panels for the KX3 arrived and took only 5 minutes to fit (including finding the correct screwdriver). The perspex cover is on backorder but the side panels are already protecting the knobs

The "knurled whip" sleeves arrived from Budipole and now the whip on my active antenna doesnt wave around. I might be persuaded to make another PAC-12 Antenna now as it will be more robust.

The DFS30 multiplier to be used as part of the new W5HN 6m arrived from G4HUP in England in an impressive 4 days (faster than I get mail from Austin 200 miles south!)

Finally an MFJ 6m folded dipole arrived so I can test out the 6m beacon and keep an eye on the band!

Hamcom 2013

June brings the annual Hamcom hamfest to Dallas, which as always clashed with the ARRL June VHF contest.

As in the last three years I volunteered to help man the Elecraft Booth, but this year there was a change as Eric WA6HHQ and wife would not be attending, but I would get to work with Lisa, who I had spoken to a lot while placing orders over the phone, Dave  and Bob K6XX who I had spoken to but never met.

The trade show exhibitors this year started earlier at 0800 and officially closed at 1800, making a long day. Lots of questions, the most popular being "When can i get the KXPA100 100W PA for the KX3" , which was on display. The other new Elecraft item for me was the K3/0 mini, which is a remote front panel for remoting the K3 in a just sufficient box; you wont need to carry a full size k3 box in future. Bob was remoting his HF station in California using one, which worked as well as the Plano conference centre's wired internet would allow (horrible latency/reliability). The ISDR app for the Ipad to produce a panadaptor display (demonstrated by Eric at last years Hamcom) for the KX3 also generated a lot of interest, but a lot wanted an Android app!

I did see a useful  aftermarket product for the KX3 which was an extended pair of sidepanels and a perspex cover to protect the front panel knobs on the KX3. http://gemsproducts.com/covers.html So useful i ordered a set Sunday morning

The outside flea market wasnt too exciting, but i did get a GPS board with CDMA modem assembly for $1. The Inside Fleamarket produced a couple of the HP 12V 47A PSU (like i used to power my 100W 3400MHz PA) for $20 each and a Flexible solar panel. I also discovered that Buddipole now have a "knurled whip sleeve" to put over the telescopic whips with the 1/4-20 thread (as I use on my PAC-12 HF antenna) to stop the whip assembly wobbling in its ferrule, so I ordered a few

I did get to meet John Langridge. KB5NJD who also operates on LF as WG2XIQ, a station i hear often on 474.2kHz. Unfortunately I could not get to his talk, but I did persuade him to email me his Powerpoint which made for interesting reading.