Monday, March 22, 2010

QRP & a NAP - Baby Carriage Portable

This weekend, the sun finally poked out so baby Isabella and I were out for a walk. As babies do, she took a nap (we were at a noisy ball field, so a long walk around the back end of park was a lot quieter for both of us.) Also on the back of the All Terrain Baby Carriage was my FT-817 and a MFJ-1899T with a counterpoise.

The MFJ-1899T, is is a fascinating mini-antenna for on-the-spot HF'ing. It is made by Waters and Stanton of the UK and imported to the US by MFJ Enterprises, I got mine at HRO.

This multiband rig is similar to a miniature Outbacker, with band taps along its lower helical winding section, a jumper lead for selecting bands (wander wand), and a top mounted pull-up whip. The base is fitted with a BNC connector to mate with the FT-817’s front socket.

The MFJ-1899T “Walkabout” antenna covers 80 through 2 meters in a single “break apart and carry anywhere” package. Fully extended, it measures 63 inches in height. Retracted and separated, the helical base section is 12 inches long and the pull-up whip is 7 inches long. Adding a BNC-to-PL-259 plus a right angle PL-259 adapter and connecting it to the stronger SO-239 socket of the FT-817 relieves strain. That same idea also works for adapting the MFJ “Walkabout” to other transceivers (FT-857). But dial it down the output below the antenna’s limit of 25 watts.

It is the counterpoise, that is the key to making this little antenna perform. -- The instruction sheet suggests it need not be 1/4 wave long. In fact, the info sheet suggests using the formula 180/F(in MHz) = Length (in feet) of the counterpoise. I use a 16ft section for 40m & 20m and seems to work well enough, I used stainless steel cable covered in Teflon available at HOME DEPOT.

Isabella, slept for a little over an hour and half. When she awoke, we walked back to where the rest of the family was enjoying the ball games. She was rested and I was very happy to have worked a few stations on 20m QRP.

NOTE: I also listened for k4ESA on 10m, but did not hear anybody local, just lots and lots of South American stations calling, 10m is working well in the afternoon.

Monday, February 22, 2010

New Amateur Radio Digital Mode - ROS

ROS is a brand-new Amateur Radio digital spread spectrum mode with the first HF contact taking place this week. -- The first contact with ROS took place on February 18, 2010, at 20:56 UTC from Vitoria in Spain to the University of Twente in the Netherlands covering a distance of 1265 Km on 7.065 MHz.

Although it's only 4 days since the first HF contact with the new Amateur Radio data mode ROS, it's proving popular with plenty of activity on 14.101 MHz.

ROS is a digital spread spectrum mode but with a narrow total occupied bandwidth of about 2.2 kHz (similar to SSB Voice). The software has two Symbol Rates: 16 and 1 baud (the latter aimed at weak signals down to incredible -35 dbs of S/N) and can automatically synchronize any Symbol Rate.

Initial reports in Europe (See Caution Below for US based HAMs) talk of it being able to copy signals so weak that they don't show up on the Waterfall and there are early indications that it is several dB better than Olivia. However, HF with its Fading, Doppler, Multi-Path and Interference is a hazardous environment for digital signals and only time will tell how well it performs against the other modes.

 ... see my previous report on very robust signals -- -- (as you recall, WSPR will currently do -29db)

The HF frequencies currently used for ROS are USB 3.600, 7.053, 14.101, 28.300 MHz

To use ROS you just need your HF radio, a PC and a basic PC sound card interface, similar to PSK31 or WSPR.

The software for ROS is free and you can download it along with the User Guide and Introduction to ROS Spread Spectrum at

A Word of Caution -- Here in the United States there the FCC specifies which modes Amateurs can use and where on the bands. Some USA Amateurs are concerned that FCC regulations appears to prohibit the use of Spread Spectrum below 420 MHz and ROS is a Spread Spectrum mode. It is a very narrow Spread Spectrum same as voice, but the devil is in the details. -- To be fair to the FCC they did try back in 1977 to change from a mode based band plan to one based on bandwidth. At the time the ARRL opposed the change and was successful in defeating it, as a result the development of digital modes was crippled for decades to follow.  In recent years the ARRL has been trying to get the FCC to re-introduce band planning by bandwidth and hopefully they will be successful.

So for now, this ham is in ROS/SWL only.

Re: Some of this information came to me via the south gate club.

Monday, February 8, 2010

[LxPeditionsAtlanta] 2nd Annual Mid Winter 10 Meter Lunchtime LxPedition is February 11th at High Noon

OK Gents;

The snow and rain are gone, the ground hog has done its jig, and the Saints have won the superbowl. -- Mean while in the world of ham radio the 10 M band is opening some, time to dust off the LX 10M gear and have some fun at lunch.

This Year's 2nd Annual Mid Winter 10 Meter Lunchtime LxPedition is February 11th at High Noon. -- 28.430 main calling frequency, so it in Tech friendly part of the band, 12-1:00 pm. Turn on your rig and call. -- See who you can contact.

Mark you calendars and join us. If we are lucky the band will open and lots of fun will be had. After the event, please post to the group in an email where you were, what your gear was, who you heard and who you had a contact with.

Non LxPedition members can email me direct for more info, and remember, once you participate in an event you can join the Yahoo group to keep current on up coming events.

Monitor 145.410 as the the talk-in Frequency.

Pictures are from Previous Events

Friday, January 29, 2010

An Evening with Martin F. Jue, founder of MFJ Enterprises

The Georgia Tech Amateur Radio Club and the Atlanta Radio Club are pleased to announce a community event that should be of interest to all hams:

An Evening with Martin F. Jue, founder of MFJ Enterprises

Thursday, February 25, 2010 at 7:00 p.m.

Georgia Tech
Van Leer ECE Building
777 Atlantic Drive, Atlanta

Everyone is invited. Come one, come all. Bring your friends.

There will be a Q&A session with Martin after his talk. Here's your chance to get your MFJ company or product questions answered by the ultimate MFJ insider, the MFJ of MFJ, if you will.

Admission is FREE and a FREE door prize drawing will be held for some cool prizes, including MFJ-259B antenna analyzers.

Refreshments will be served. // Talk-in will be available on the GTARC (W4AQL) and ARC (W4DOC) repeaters. // There may also be a few surprises. // Additional details, such as the event program, will be available in a few weeks.

Did you know that... The Georgia Tech Amateur Radio Club is celebrating its 100th birthday this year, which makes it the oldest radio club in the state of Georgia. The Atlanta Radio Club is a close second.