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Reviews For: Times LMR coax

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

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Review Summary For : Times LMR coax
Reviews: 27MSRP: varies
Description:
Low-loss coaxial cable, hardline, and connectors.
Product is in production
More Info: http://www.timesmicrowave.com/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00274.4
K1FO Rating: 2001-04-30
Very good for ham use Time Owned: more than 12 months.
I have been using LMR-600 as flex cables around the rotor on 144 & 432 MHz for at least 5 years. It's been so long I don't remember as I got the LMR-600 within a few months after it was introduced. In intermittent amateur operation I have had no problems running 1500 watts through it on both 144 & 432 MHz and 200w on 1296 MHz. This includes a lot of CW EME work on 432. Moreover, my entire 432 array rotates in polarity. During EME operation I'm constantly rotating polarity which places a lot of stress on the cables. As I said, 5+ years with no problems. The LMR-600 replaced Andrew FSJ4-50B Superflex. I got rid of the Superflex because I could not keep water out of the Superflex. The large air volume between its dielectric & shield just made it suck water in no matter how I tried to seal the Andrew conectors. LMR may not be suitable for 1500w 24x7 but that's not typical amateur operation. By the way Andrew LDF4-50B has a copper clad aluminum center conductor, so the copper clad center conductor in LMR should not be a problem.
KC4TXR Rating: 2000-12-29
Best Coax Ever Made, Bar None Time Owned: 6 to 12 months.
I've used LMR-400 ultraflex for over a year now. Personally and professionally (at 1.5GHz). It's wonderful! It's super high quality cable. It's extremely durable. It will handle far more power than you will ever throw at it. It really is low loss. Do let some moron install connectors, insist on an IQ that's at least triple digits. If you have a double digit IQ, stick with RG-58.
N3HKN Rating: 2000-12-22
Skin Effect-Heating Time Owned: 0 to 3 months.
The issue seems to be that the copper cladding may overheat if the conductive path of the thin cladding is even partially interrupted by a "nick". This is quite understandable since RF flows only on the surface of a conductor. A nick becomes a point of somewhat higher resistence. One would guess that a nicked center conductor at 100 watts would be alright. However, a ham with the desire and dollars could hit it with over a KW using ATV and cause it to heat the cladding that is dirctly opposite the nick.
Dick N3HKN
WB2WIK Rating: 2000-12-22
LMR400 = problems, sometimes Time Owned: 0 to 3 months.
I had occasion to evaluate LMR400 for commercial applications, where many miles could be used in total, and short lengths would need to conduct more than 1 kWccs in the VHF-FM BCB. Based on a 168-hour long evaluation, we had to reject the cable as unsuitable for high power applications, due to its use of copperclad aluminum. It is nearly impossible to install a connector on this cable without scoring the center conductor, at least a little bit, in the process of stripping away the dielectrics. That scoring, even a few thousandths of an inch deep and not noticeable to the unaided eye, exposes the raw aluminum conductor beneath the copper coating. We wondered what this would do, in terms of reliability, so we tried a quick experiment, which was to fabricate a six-foot (~2m) cable assembly with a Teflon-insulated PL259 type connector on each end, carefully soldered by trained technicians who do this for a living, and then conducting 4.5Arms at 110 MHz through the cable, the equivalent of 1000Wrms delivered to a 50 Ohm resistive termination. The exciter used was a Gates 1kW FM BC exciter and the termination a standard Bird Electronics 50 Ohm "termaline" resistor rated 1.2kWccs to 1 GHz. After less than ten minutes, power to the load began to deteriorate, and after less than 30 minutes, power delivered dropped to zero, as the aluminum conductor of the LMR400 had disintegrated entirely where it was scored. The center pin of the coaxial connector, made of silver clad over nickel-plated brass, also showed signs of the solder melting during the test cycle, an indication of a very high resistance contact between the LMR400 cable conductor and the pin itself. We repeated the test three times using different connectors and various cable lengths, with repeatable results: Cables always disintegrated, with the root cause remaining the exposed aluminum where it was scored during stripping for connector application. This problem would not occur for "receiving" applications, or low-powered transmission; but we had to rate LMR400 "unacceptable" for transmitting at the 1kW level, frequently used by Amateurs as well.
K8QT Rating: 2000-09-05
This is Great Coax..... Time Owned: 6 to 12 months.
This is one High Quality product. It is available in a size to get you "your desired" amount of RF to the antenna. All that is limiting is $$$! It is not so much the coax cost but the cost of the correct designed connectors that stops more operators from using this. For those that do not know with LMR-400 ham operators do use PL-259s on this size to keep the cost down and get a better grade coax for the shack. It is not recommended by professionals and factory technicians but -- we all know about hams and the penny.......so it goes. They do fit on the coax - I am sure the combination and practice will never get endorsed by the company but........!

I personally feed three omni antennas with LMR-400. (6 mtr, 2 mtr & 70cm) Each feed line is a run of 110 feet. It has performed better than my research lead me to believe it would.....you can feel confident in using this product line.

The solid core center works great where you do not have any movement or rotation. If your requirements are for a rotor install look at the Flex series they offer.

Check out the velocity factor! Check out the loss for your desired frequency! The home web page for the company has a calculator for anyone to use...... The service people are great too.....

Give it a try.

It worked very well in this setup.
WB9YCJ Rating: 2000-06-30
LMR 400 Ultra-Flex Time Owned: 0 to 3 months.
For those that need a more flexible "400",
consider their Ultra-Flex 400.
WM5R Rating: 2000-06-30
Good, but stiff coax Time Owned: more than 12 months.
I have used a run of Times Microwave LMR-400 on 222 MHz for over a year. It makes an audible difference over the aging RG-8/U that was briefly in place before it. The difference isn't huge, mind you, but it's there. LMR-400 and LMR-600 seem to be a good compromise between coax of the RG-8/U class and, say, Heliax hardline.

LMR-400 is stiff enough that I wouldn't use it for rotor loops or the like.