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eHam Forums / Antennas and Towers and more / RE: MA40 tower bolts
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on: May 04, 2013, 05:48:27 AM
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Hi Greg,
I have the 15 page PDF engineering package which I'll be happy to e-mail to you if you contact me directly. You didn't mention if you are using the MAB-40 tilt base. I think the bolts are the same regardless. The specs call out four 3/4" diameter ASTM A36 headed anchor bolts of 27" overall length. The full document shows the design of the rebar cage, etc.. The rebar cage is surprisingly complex.
73, Mike K2MK
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eHam Forums / Antennas and Towers and more / RE: SteppIR BigIR Installation Early Results - Any Advice?
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on: April 28, 2013, 06:36:05 AM
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I've had a BigIR with 80 meter coil for about 6 years. As K3VAT indicated you have to use create/modify as the factory settings are seldom reliable for a vertical antenna. Your ground conditions and nearby objects strongly affect the element length.
Next, it is very important that the frequency on the controller match your transmit frequency. Do not get in the habit of moving the controller frequency to improve SWR. This is especially true on 80 meters where the coil will change its tap position at several different frequencies. The best arrangement is to utilize transceiver tracking so that the SteppIR controller follows your transmit frequency.
Lastly, with the 80 meter coil SteppIR recommends that you use 3/4 wave mode. It's only active on 15 through 6 meters but it will usually improve your SWR on those bands.
73, Mike K2MK
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eHam Forums / DXing / RE: DXers K3
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on: March 20, 2013, 04:06:54 AM
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Hi Trevor,
The K3 is a great RTTY rig. You will be able to sell your PRO2. Some people use external digital interfaces for RTTY but it is NOT required with the K3. The K3 can interface directly with your PC sound card with just 2 audio cables to produce AFSK RTTY.
73, Mike K2MK
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eHam Forums / Antennas and Towers and more / RE: minimum between hex beam and flat roof
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on: March 17, 2013, 06:17:11 AM
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The first location for my Traffie hex beam was close to the house. About 1/3 of the antenna was over the roof. The SWR would rise over 2:1 as the driven element was oriented over the roof. During that time I had the mast extended to 30 feet, 25 feet and 20 feet. The SWR irregularity was worse the lower the elevation. At 20 feet the antenna just cleared the sloped roof by a few inches. Maybe things would have been different if the roof was flat.
73, Mike K2MK
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eHam Forums / Antennas and Towers and more / RE: Hex Beam Mounting Question
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on: February 19, 2013, 04:19:25 AM
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You may see some SWR variations as you rotate the hex beam. My original mounting location had it mast mounted from the ground but partially overhanging the roof. In other words, about 1/3 of the antenna was over the roof and 2/3 was in the clear. As the driven element was rotated over the roof the SWR would rise beyond 2:1 on some bands. I don't know if it didn't like being close to the roof or if it was caused by the fact that only part of the antenna was over the roof. I haven't read about similar effects when the antenna is mounted on the peak of the roof. Of course that is not an option for you. Will it work. Absolutely. Is it worth the effort. Absolutely. If you paint, go for a flat paint. Less reflections. I've painted various items with Krylon Camouflage paint. They call it ultra-flat. It's carried at my local Home Depot but not Lowes. http://www.krylon.com/products/camouflage_paint_with_fusion_technology/73, Mike K2MK
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eHam Forums / Amplifiers / RE: new 220vac line for final
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on: February 13, 2013, 04:10:30 AM
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If you have 200 amp service then unless you have a really big house there are probably lots of spare slots. If you get an electrician to come out for a free estimate he'll explain it all to you. Even if you have no spare slots he'll fix you up. The cost is going to be mostly labor anyway so you really don't have to sweat the fine details of how he does it.
There are two things you do want to remember, however. First, go with a 20 amp circuit. That will provide you with all you need for just about any legal limit amplifier. The next is that you need to get a sensible receptacle installed in your shack. If you just tell an electrician that you need a 240 volt receptacle you might end up with a big clunky electric dryer type of wall receptacle. You don't want this. You want the simplest 20 amp receptacle. This is designated as a Nema 6-20R. The 6-20R accepts either a 15 or 20 amp plug (6-15P or 6-20P respectively). Google images of the Nema numbers to see examples.
73, Mike K2MK
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eHam Forums / Antennas and Towers and more / RE: 160M Dipole 20 Feet Above ground
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on: February 03, 2013, 07:22:21 AM
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WD4ELG:
Good questions. Working any DX is not easy for me. I usually have to wait until there are very few callers. From New Jersey I can work the Caribbean and South America whenever I can hear them. So from 0000z to about 1100z but it's always easier after 0400z.
I can typically hear Europe after my sunset but I am not able to work them until about 0500z. So yes it is their sunrise.
73, Mike K2MK
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eHam Forums / DXing / RE: Where to get IRCs
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on: February 03, 2013, 06:38:07 AM
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You can buy IRCs from some of the larger volume QSL managers that handle DXpeditions. They typically have an excess and are happy to sell them. Don't buy more than you need as they expire quickly. Send out a few e-mail inquiries.
An IRC will be redeemable for postage stamps in any country that has not discontinued their use. So yes it is legal. It's best to follow the advice provided on the ham's QRZ page. Some only want green stamps and some only want IRCs.
73, Mike K2MK
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eHam Forums / Antennas and Towers and more / RE: 160M Dipole 20 Feet Above ground
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on: February 03, 2013, 06:22:33 AM
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Hi Bob,
My 160 meter full length dipole has an average height of about 10 feet. The center is about 12 feet high. I only use it for 160 meter contests and the results continue to astonish me. Running 200 watts I achieved WAS in two winter contest seasons. Now running a KW I've managed to work and confirm 57 DXCC entities.
In the CQWW 160 meter contest a couple of weeks ago I had 479 contacts which included 46 states and about 30 DX contacts. All search and pounce.
I'm feeding it with around 300 feet of RG8 coax and the 2:1 SWR bandwidth is over 1MHz. The antenna is also pretty quiet. Forget the modeling and just do it.
73, Mike K2MK
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eHam Forums / Antennas and Towers and more / RE: Traffie hex beam - why so pricey?
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on: January 30, 2013, 08:30:52 AM
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Kravitz Kravitz Kravitz Kravitz Kravitz Kravitz Kravitz 600.00 you could have saved Kravitz, think about it ? That 600.00 could have bought you a little amp, or at least paid for a lot of Bagels Oh yes, I got your message loud and clear. Thanks for the enlightenment. K2MK
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eHam Forums / Antennas and Towers and more / RE: Traffie hex beam - why so pricey?
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on: January 30, 2013, 05:22:47 AM
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Hi Lane, Competition is a great thing. We all benefit from the fact that there are several very high quality hex beams available for sale. The Traffie 5 band hex beam is extremely robust. It is also smaller in diameter and a bit lower in weight. If any of these three things is important to you then you might be willing to pay the higher price. I have mine on a Rohn H30 mast and when I first installed it I had deviated from Rohn's published guy recommendations. As a result, during a wind storm, the mast buckled at about the 12 foot level and the top 18 feet of mast with my Traffie beam at the top smacked into the ground. Rohn mast, total loss. Traffie hex beam not a scratch. It's back up on a new properly guyed H30 mast. By the way, KA7NIQ does not own a hex beam and is a Traffie basher and has done so on several different threads. I suggest that you read the reviews for all of the available hex beams and listen to the voices of experience. Then join the Yahoo hex beam group and make your decision. http://groups.yahoo.com/group/hex-beam/73, Mike K2MK
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