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Russ Woodman, K5TUX, co-hosts the Linux in the Ham Shack podcast which is available for download in both MP3 and OGG audio format. Contact him at [email protected].

The weather here has sure cooled down and had 20cm of snow on Saturday this will at least make the ground white. At the old place there is a pile of snow but here in the city not so much.....speaking of not so much that has been the progress with my antenna situation in the condo. I have not really had all that much time to try anymore idea out. My next plan of attack  will be to place the Alexloop on the balcony in the horizontal position (in the cover of darkness of coarse) and see how that does for both receiving and transmitting. I have now narrowed my antenna selection down to two antennas, the MFJ 1788 loop or the MFJ 1780 fan box loop. I contacted MFJ and asked their opinion and was told the 1788 was a better construction and the 1780 was more portable but both are good antennas! Well that really didn't  help much. I called the local ham dealer and they do not stock the fan box loop and the 1788 has been on back order since October!!
I am tending to lean towards the fan box loop as it looks nothing like an antenna as the last thing I want are the condo cops coming after me. This unit is not really made for rain and is "portable" meaning I will have to take it in and out when using it. As for the 1788 it sure is more money but it covers more bands and is built better and I am a firm believer in you get what you pay for! So my delema is which antenna to go for.......
The 1780 fan box
1. It is cheaper but that may not be a good thing
2. It looks nothing like an antenna.
3. Very portable so small footprint.
BUT
1. Only covers from 14-30 meters
2. Not good in bad weather due to housing construction.
3. Has to be taken in and out.

The 1788
1. Covers from 15-40 meters
2. Solid construction
3. Able to be left outdoors year around.
BUT
1. The cost is more.
2. It looks like an antenna
3. May be hard to hide and hiding it may affect it's preformance.

Some exciting news regarding my signal getting out in this concrete jungle!
I was able to get the loop out and in the horizontal position and it worked great! The receive was very good and I was able to finally get spotted on the RBN. This are only U.S spots but with 5 watts and up to this point batting ZERO in the spot dept I am thrilled to see that my signal is getting out. Now I just have to fine tune things. At this point I have not tried WSPR but now that the horizontal position seems to work that is my next step to see how I do using WSPR.
 
Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

Paul Stam, PC4T, is a regular contributor to AmateurRadio.com and writes from the Netherlands. Contact him at [email protected].

No, I’m not expecting any new radio related ironmongery or a new rig. Especially as this week seems to have cost me a small fortune ( I had to buy a new car but that’s another story). Bust Christmas can give you a little bit extra, time that is.

I’ve only planned on doing 2 things, one is to activate the clubs callsign MX0WRC on Sunday, something that hasn’t been head on the air for a while. After refurbishing the shack the temporary antenna came down in the strong winds we regularly get so a Delta Loop will be helping us out. The plan is to show a few of the more novice operator how to use the clubs kit in the warmth. So if you hear a feint CQ from far off Cumbria then please call back. You may make a novice’s day.

The other little job will be to give away a few points in the RSGB VHF Christmas Cumulative contest. I’ve long lamented about the poor VHF signals that make it into St Bees but with a fair breeze I should work a few stations further afield than GD land (about 40 miles across the Irish sea). I’ll probably do it from the house so the QSO’s will be less than 10 but hey its only a bit of fun.

So If I don’t hear you or work you on Sunday then I hope to try again between 26th December and the 29th December for some armchair operating. Tea and biscuits at the ready!

Alex Hill, G7KSE, is a regular contributor to AmateurRadio.com and writes from Cumbria, UK. Contact him at [email protected].

The Model One has been a huge success. But in many ways it is a daring retro design judging from all the features that are missing in this radio. I am thinking of features such as a customizable equalizer, a digital display, and memory presets. It just has a plain old analog tuning dial for FM and AM.

The radio could as far as I can tell just as well have been made in the 70’s except for some of the IC’s which are used. Actually it is easy to see the similarity with the even older KLH Model 18 from the 60’s, and yes – Henry Kloss played a role in both radio designs. But that makes for easy repairs, such as a seemingly common fault in the FM tuning capacitor, which over time may develop contact problems.

The radio is in many respects exceptionally well made. The tuning dial has a quality vernier drive. The audio section is well built with a powerful amplifier, a strong magnet for the loudspeaker, and a bass port design for the wooden cabinet. All are factors which contribute to its reputation for good audio. If one can trust measurements on the web, it has been equalized for enhanced bass and treble with the mid’s some 6 dB down. These are well-known tricks for getting a warm and crisp sound with universal appeal. Internally the tuner section, which is built around the TEA5711T chip, is well shielded for frequency stability as seen in image 2.

One weakness which manifested itself after only 3-4 years in this particular radio is that it became hard to tune, scratchy, and unstable on FM due to intermittent contacts in the tuning capacitor. According to the TEA5711T datasheet it is a varicon which for AM has 140/82 pF, for FM 2 x 20 pF, and for trimmers 4 x 8 pF. This particular unit had a Mitsumi varicon. Some say, when this fault occurs, that the varicon must be replaced and others say it can be cleaned. Who do you think I sided with?

Disassembling the radio is quite straightforward if you are used to this kind of work. The tuner is enclosed in shielding on both sides of the PCB. The shields can carefully be desoldered as shown in image 3. That exposes the varicon, and its plastic casing can be lifted as shown in the last image.

I sprayed it with contact spray and the radio came back to life. The only problem was that the tuning on FM had shifted so that a station on 100 MHz now appeared on 107 MHz. A little detective work around the circuit showed which trimmer that was for the FM oscillator and which one that was for the FM RF circuit (marked O and R in image 2). Since the oscillator trimmer was set for its maximum capacitance with the plates covering each other, it was easy to reduce the value and get the FM dial back to normal again, and then to peak the RF trimmer.

It got me wondering though to see that it had been necessary in the first place to have the oscillator trimmer set at its maximum value. It was just as if the tuning capacitor never had had its full value, even in the factory, and that it finally got it after my cleaning.

Sverre Holm, LA3ZA, is a regular contributor to AmateurRadio.com and writes from Norway. Contact him at [email protected].

As we move past the peak of this current solar cycle it seems that we are enjoying some of the best conditions on the high bands in several years. However, there does seem to be a sense of urgency to enjoy 10 meter DX since these conditions will likely last a few weeks rather than a year or two as in past cycles. I remember when I received my Novice license in 1989 that 10 meters was so busy you could hardly find a spot to call CQ in the Novice band, 28.300 - 28.500.

Since the flux has been in the 160 -170 range lately, last week's 10 meter contest was full of activity. It was a great opportunity for me to increase my QRP DXCC count which was at 160 entities worked going into the weekend. The bottom line, with the exception of V55V on SSB, I was able to work everyone I chased. It was harder work that I thought it would be, which is a testament to how busy the band was.

So with the band hopping, I fired up the KX3 and went hunting. I was able to work TK5EP, 4O3A, OX3XR on CW and ZS1TMJ on SSB. It was Saturday morning when I made these QSO's, so it was still early in the contest, I'm sure on Sunday, these stations would have been a little easier to work. I picked up four new counters on 10m and threw in FG5FR on 15m to get my QRP DXCC to 165. It was a fun weekend and it's good to hear some much activity on 10m.

So, go have a look at 10 meters, better yet, call CQ. You mght be surprised who comes back.
Mike Crownover, AD5A, is a regular contributor to AmateurRadio.com and writes from Texas, USA. Contact him at [email protected].

AmateurLogic.TV Episode 61 is now available for download.

It’s the AmateurLogic Christmas Spectacular. Join the crew and special guest for a festive holiday event.

Peter hacks his Degen SW Receiver. Tommy puts the Arduino on TV. George trudges on in his effort to use the Raspberry Pi as an Echolink node. And a hilarious look at the 2013 ALTV Holiday Gift Guide.

A 1:13:08 AmateurLogic celebration of the season and other good stuff.

Download

View in web browser: YouTube

George Thomas, W5JDX, is co-host of AmateurLogic.TV, an original amateur radio video program hosted by George Thomas (W5JDX), Tommy Martin (N5ZNO), Peter Berrett (VK3PB), and Emile Diodene (KE5QKR). Contact him at [email protected].