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RG-6 is 75 ohm coax so it is OK for receiving but doesn't match most transmitters
that 50 ohm output.

I believe the antenna Rich is talking about uses a 300/75 ohm matching balun included to connect the coax to the antenna.

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Jim N7UAP - Bellingham, WA / InterceptRadio.com

Yes, because of the mismatch you end up having an SWR of 1.5

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Also with the RG-6 with it's higher impedance it has lower loss than it's 50 Ohm counterpart (RG-8X). That is better for 800MHz. For RX only that should work just fine as long as the connectors are all done correctly.


Jim

Bingo. As for connectors you can get compression type BNC connectors at Home Depot for RG6.

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As Rich pointed out, RG-6 or RG-11 is also my preference for coax for receiving antennas. Here's why ~

-- we are normally told to use 50ohm coax for a 50 ohm antenna. That's to provide a good SWR match.

-- But, since we are not transmitting, we don't care about a slight SWR mismatch for connecting a 50-ohm antenna thru a 75-ohm coax. The SWR mismatch for 75-ohm to 50-ohm is about 2.1 to 1, not significant for receiving.

-- Typical prices for RG-6 are about 6 cents per foot. I didn't check prices for the recommended LMR coax so will rely on someone else to educate us. Why so low? RG-6 is used by the satellite and cable TV folks so the lower price compared with other coax prices is significant. It's all about demand driving prices down. As a comparison, I'm shopping for RG-8X for some wire antennas as I'm getting back into HF as a ham radio guy. I haven't exhausted my search (Rich--give me some tips for cheaper price) but the lowest prices I've found so far is 30 cents a foot for lengths at least 100 feet from a place on the web called Wireman. So RG-8X is five ties ore expensive than RG-6.

-- The other thing I like about RG-6 is that my satellite and cable company gave me a bunch of odd lengths and I wound up with close to 200 feet of RG-6 of various lengths for free! Just ask. When I see a Comcast and DirectTV, etc. truck in my area, I stop and ask. Amazing what they've given me.

-- RG-6 RG-11 is a bit of a challenge to get a connector on it so I bought a connector-cable crimper from RadShak for about $20. If RadShak makes you barf, get one on the web.

Wonderful, now that I can handle. I'm not against Radio Shack, at least if it doesn't work I can take it back easily. Admittedly some of their stuff is not the best.

Was looking at possible locations and decided not to use the TV antenna, instead go off the porch roof witch will make a much shorter run.

I thank you all for that helpful information. Now to find the stuff.

I have the big red RadioShack coax crimpers and actually I find them one of the better crimp tools I have used.

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I bought the Antenna Craft ST2 about 2 months ago and so far have been very happy with it. From box to installed on the tower was about 20 mins. It's comes with 50 ft. of RG-6 coax a F-BNC connector and matching balun. You won't need to buy anything else. I have it mounted below a RS ant. and it outperforms the RS in all freq. ranges.

I'll second what others have said about coax, but for general use go with the less expensive coax. Unless you have a very fringe frequency you must hear the extra 2-3 db you gain with $$$ coax isn't going to buy you much. As Dennis suggested, hit up the Comcast, Direct TV, Dish Network guys and they'll often have left over end pieces or lengths of old coax they've removed. It's all thrown away, so we might as well use it!..... :D

How do yo suppose I ended up with literally TONS (honestly, thousands of pounds :mrgreen: ) of surplus electronics appropriate for what we do??? Have a whole bunch of 900 Mhz commercial antennae that I could never hope to use in a lifetime :mrgreen: AND they make pretty decent RX thru 800... At least my spectrum analyzers think so :shock:
PLUS if you take those old Spectras that won't listen to trunking anymore and mod them up, then there's another underutilized ham band(33cm) you could get on, CHEAP! (IF you are licensed, that is-- HINT :mrgreen:

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That is how the people at DARPA think. they take things and use them in unconventional ways, to see what happens.

anyone ever use RG-59U for any scanner antenna setups? I'm not using this now but have a good length of it and was wondering if it's even worth it?

For LMR-400, check eBay.

I have purchased LMR-400 several times off of eBay with very good value.

Takes some looking around, but name brand deals can be had generally has N-Connectors installed.

If you need different connectors or adapters ask the seller. One seller threw in two 90 degree N/BNC adapters value added.

100 feet, brand new, Times Microwave, N conns installed w/BNC/N delivered for $60 is pretty reasonable.

My.02 cents.

Regards,
Mike

Boeing Surplus back in the day, (70s-80s) was a goldmine for the budding Ham radio operator like myself. Copper wire sold for .20 a lb. Aluminum tubing to die for if you hit it just right. .25 a lb. I picked up a load of 18 ft. 1 inch and 1.25 7075 tubing along with 4 lengths of .25 wall aluminum masting. I don't know what it was made of, but that 16 ft piece held up a 4 element 15 mtr yagi and a 3 element 20 mtr. yagi in a 100 ft. tree for many many years.

I hauled that load of tubing home in my Toyota Tercel on a roof rack and sticking out the windows. Ahhhh the good ol days. RIP Boeing Surplus! Yes, there are still lots of good deals out there, many free. I haven't bought coax in many years.

RG-59 works fine, I wouldn't want to go more than 50 ft. though.

Thanks for that information on the AntennaCraft ST 2, just ordered it. Seems it would be cheaper, shipping and all, than going to the local Radio Shack and buying their antenna and cable, even without adding the nearly 10% tax.

You have been most helpful, thanks again~