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Reviews For: Radio Shack TV Twin Lead

Category: Feedlines (coax, ladder-line, etc.)

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Review Summary For : Radio Shack TV Twin Lead
Reviews: 23MSRP: 3.99
Description:
300 ohm TV Twin Lead
Product is in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00234
K1ROD Rating: 2002-03-14
Good stuff Time Owned: more than 12 months.
For the price, this is really good stuff. I have been running it up to an unsupported center insulator on a homemade G5RV. I put it up about a year ago thinking it would last about a month. It's still there, swinging in the breeze. I also thought I would see some very interesting fireworks when I lit up the 30L-1 amplifier. 800 Watts later, no problem. I also thought the Phoenix Sun would eat it alive but still....no problems. For the money, you cant beat it.
N6CBS Rating: 2002-01-14
Held up to sun and pollution for 5 years Time Owned: more than 12 months.
I Love Radio Shack 300 ohm twin lead. I used it to feed a 4 element folded-dipole Yagi on 2 Meters and for my 15 M folded-dipole. Both antennas have been up on my Los Angeles roof for about 5 years so far. I did not experience any cracking to the black plastic cover due to Los Angeles UV radiation or air pollution.

Twin lead is the best kept secret in Amaetur radio. Electrically, it has lower electrical loss than any coax you can purchase, it is light weight and painfully inexpensive. You don't have to spend gobs of money with heavy, large diameter coax cable to get low electrical loss. Ideally, the 300 ohm twin lead has been a favorite transmission line for UHF Television, but you can use it in the HF bands. I have used it on the 40M and 15M bands because of it's low loss and light weight.

The 300 ohm twin matches nicely to any half wavelength folded dipole antennas which have a resistive impediance of about 257 ohms. Ref. See Kraus, "Antennas".

For high power, make sure solder connections are smooth. I ran 500 Watts SSB on the 15M folded dipole and burned the solder connections. After replacing the burned twin-lead, resoldering, I took extra care to make the solder joints clean and smooth.

I used a 4 to 1 ferrite balan at the output of my antenna tuner to feed my transmitter to the 300 ohm twin lead. If you do your math the VSWR match is about 1.5 to 1 min. I use the antenna tuner to touch up the match to an easy 1.0 to 1.

The 2M band balan is easy. A coaxial balan, I used 0.250 in semi-rigid coax for the coaxial part. Look in any antenna handbook for a coaxial balan designs. I did not use an antenna tuner at the output of my tranceiver. I could live with the 1.5 to 1 VSWR match.

Try the Radio Shack, or any other 300 ohm line. I would avoid the really inexpensive stuff because of the UV and air pollution exposure will make your transmission line crack and deteriorate in a short amount of time.

KO4NR Rating: 2001-08-29
Biggest Conductors out there I've seen!! Time Owned: more than 12 months.
Finally found 300 ohm TV Twin lead with conductors large enough that you can work with them without breaking them. This twin lead is easy to work with and is tough. I was very surprised at the quality of it. Make really good feed line for my antennas.

Be carful when stripping off the insulation!!
73,
Bill Smith KO4NR