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Do you listen to local ham radio repeaters?


OwlG
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Thanks alot man im new to all this stuff was finding it hard to find good info on what im looking for that site has everything thanks again :)

sorry if these are the stupidest questions ever but should i be on NFM or AM when listening to these and what width should the filter be

and also sorry again but what kinda antenna should i have for these i have a marine antenna its pretty small

Edited by james92
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  • 4 weeks later...

Hey James sorry for the late reply. Use NFM and start with a wide filter. If your marine antenna is in the 162 MHz range it will work fine. Most repeaters are on towers or tall buildings so they usually have a pretty good signal.

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Thank's :) I'm very curious about getting on the 6 meter's band but I'm a complete super noob I would love to listen to the ISS what do you think would be the easiest way for me to get on there? I tried making a 6 meters band delta loop but I don't think I done it right I find it a bit confusing ha I have a few different old tv antenna's some are big bunny ear's and some are powered circular kinda antenna's their all pretty old do you know what they could would tune in to well?

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  • 3 weeks later...

Nope don't have a license or the equipment to transmit just have small dongle for receiving.

My question was worded badly what is the easiest 6 meter's band antenna to make at home?

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That's easy, a 1/2 wave dipole. You will need 10 feet of wire, three insulators, a bunch of 75 ohm coax with the appropriate connector for your dongle on one end (TV coax will work fine but avoid using the really stiff stuff) some wire cutters and a soldering iron and solder. The formula for making a dipole is simple; the 1/2 wavelength in feet is equal to 468 divided by the frequency of interest in MHz. so 6 meters is 50 MHz and 468 divided by 50 equals 9.36 which is 9' 4 3/8". Dipoles are typically center fed through a balun (or transformer) for transmission but we don't care about matching that impedance so a simple insulator in the middle to split the length into 2 equal length pieces, each being a quarter wavelength or 4' 8 3/16" but leave about three inches of extra length. Connect the center of the coax to one leg and the coax braid to the other and secure those joints mechanically with one of the insulators to hold them apart and from being ripped apart and viola! Attach a remaining insulator to each end to make the measurement at each end become the desired length and then string that puppy up as high as the coax will let you while still connected to the dongle and orient the elements broadside to the listening direction of interest. Coincidentally, to make a 1/4 wave vertical antenna the same formula is true but braid needs radials to make the ground plane. With the center element connected to the center conductor of the coax pointing straight up 4' 8 3/16" with 4 or more radials of the same length plus 10% pointing in a North South East West configuration with the horizon, then the antenna is Omnidirectional. The collinear antenna Darren made will provide more gain but will get huge at 6 meter frequencies. It's design uses the same formula and you get the idea. A two section collinear is 9 feet tall and so on. And then there are monsters like this one...

http://www.m2inc.com/index.php?ax=amateur&pg=116

Not cheap but GAD ZOOKS it's huge! 70' boom and 83 lbs. :ohmy: - KD6W

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Thanks I'm going to get some of the parts tomorrow watched a few more video's on making them and kinda starting to understand this a bit better now.

Which type of coax would be the best to get for this and would there be any alternative to the insulators could I make one instead because I'm pretty sure I won't find them around here

That boom is deadly what happen's if it get's hit by lighting will that not fry everything connected to it

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Use stranded copper wire for the elements. Any durable plastic thick enough to take strain will make a good insulator. I have used chunks of white PVC pipe and acrylic squares to strips of phenolic board material. When ever I see a porcelain insulator at the flea market, I pick them up and then promptly loose them on my bench. The coax you choose will likely be for economic reasons. Using RG6 coax will serve the purpose for reception applications. You aren't transmitting so any coax will work but I should caution you the light duty stuff will not work as well at the higher frequencies. All coax has a frequency chart like page 6.6 in this link... http://www.belden.com/resourcecenter/tools/cablefinder/upload/06-3_15.pdf

The chances of getting struck is dependent on where the tower is located geographically and how far above the antenna is to everything else around it. My antennas don't exceed the height of the natural tree canopy around me but I don't have a monster like that one either (though I wish I did!). The DC resistance of the antenna is near or at ground potential to the tower it's mounted to. So, if the antenna takes a hit, the path of least resistance will shunt the blast, usually down the tower. If some of the charge goes down the coax and no way to dissipate the charge into a protection ground, any equipment connected to it will carry the path to ground and likely let a bunch of magic smoke out in the process. - KD6W

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