Awful quality RG174 going around - be careful! - Page 1
Forum section: electronics / testgear

author: tkamiya
author_rank: Super Contributor
timestamp: September 13, 2018, 04:09:15 pm
content: I've been looking for a good RG174 - with BRAIDED shield layer with fairly dense (80+?) coverage. In other words, nothing special.I've ordered two RG174 on Ebay. What's pictured here is what I received both times. Please notice, the shield is not braided and coverage is like 50%. Another commonality is outer jacket is shiny and realy really STIFF. In comparison, Belden makes one that's tinned, braided, and nice and flexible.What I have here won't be good on RF other than, maybe, for HF use. I'm going to toss it in garbage if seller doesn't want to take it back. I'm SO disappointed!I posted here on TEST EQUIPMENT forum to get a widest possible audience. If that's not appropriate, please move it or delete it. (Hi, Mod!)

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 13, 2018, 04:38:40 pm
content: Quote from: tkamiya on September 13, 2018, 04:09:15 pmlittering is not good. mail it to me i am a broken RG174 collector. here is the performance i realized when i got my VNA after possessing the cable for the longest time....https://www.eevblog.com/forum/projects/performance-of-china-50-ohm-coaxial-cable/msg1476232/#msg1476232but ironically it and a diy yagi antenna did help improve my mobile broadband reception last time.

author: Bassman59
author_rank: Super Contributor
timestamp: September 13, 2018, 05:06:57 pm
content: Quote from: tkamiya on September 13, 2018, 04:09:15 pmYou should probably order from Pasternack or other proper cable supplier, and not hope that a eBay store will sell you anything good.

author: tkamiya
author_rank: Super Contributor
timestamp: September 14, 2018, 12:42:14 am
content: Actually, my eBay experience is surprisingly good. Most of the time, I get what I paid. Unfortunately, these days we are reliant on Chinese manufacturing for just about everything. Ebay gives them an outlet to sell directly. Of course, there are a few that goes sour like this one. I guess I have to take bad with the good. Kind of strange economy going on in the world now that Amazon and eBay are major players.Luckily, I have a local source. So I bought 200 feet of Belden from it today. Paid a going rate, which is few times more than what I paid before. Happiness restored. No money lost. All bodily functions in tact!

author: tkamiya
author_rank: Super Contributor
timestamp: September 14, 2018, 12:45:04 am
content: Quote from: Mechatrommer on September 13, 2018, 04:38:40 pmWell, if you really want it, I'll give it to you. My ebay posting on this is.... (JUST KIDDING!)Pay shipping and it's yours, if you are serious.I just learned very recently that eBay's first ever sale was a broken laser pointer to a "broken laser pointer collector".

author: xrunner
author_rank: Super Contributor
timestamp: September 14, 2018, 12:47:45 am
content: Quote from: tkamiya on September 13, 2018, 04:09:15 pmReally? Wow lucky here. I guess I've never seen that. How are the strands arranged in there - randomly?

author: tkamiya
author_rank: Super Contributor
timestamp: September 14, 2018, 01:49:33 am
content: On this one, strand of wires are arranged precisely randomly around the center conductor. It's hard to tell but it appears to basically run straight longitudinally. I cannot see any twists.I have another similar RG174 that the same wire kind of sort of meander through a circular fashion along its length.It basically look like a really cheap shielded cable.I guess someone didn't know RG something cable are supposed to follow MIL spec.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 14, 2018, 02:14:54 am
content: Quote from: tkamiya on September 14, 2018, 01:49:33 amlook closely, its braided (interweaved) but with much less copper.

author: tkamiya
author_rank: Super Contributor
timestamp: September 14, 2018, 03:23:44 am
content: I did. What looks like a weave is a result of my playing with it. (not intentionally)If I just peel carefully, there is absolutely no weave.

author: joeqsmith
author_rank: Super Contributor
timestamp: September 14, 2018, 04:40:25 am
content: Odd. Looking at the texture of the jacket, it seems woven. Razor blade to remove a section the jacket would clear that up.If you know the Belden cable you want, why not just get it? I think Digikey carries them.

author: tkamiya
author_rank: Super Contributor
timestamp: September 14, 2018, 05:23:35 am
content: That's what I should have done.In fact, I did check pricing on Digikey. Got scared and ran away. At least I saved some $$ by going local. No shipping. This is yet, another instance where trying to save some isn't worth the trouble.

author: Berni
author_rank: Super Contributor
timestamp: September 14, 2018, 05:24:13 am
content: I seen some even worse cable where the coverage looked more like 30% to me.No idea where that cable was from as i picked it out of the cable junk bin when i wanted a length of coax for a sensitive small signal.

author: xrunner
author_rank: Super Contributor
timestamp: September 14, 2018, 11:47:21 am
content: Quote from: tkamiya on September 14, 2018, 01:49:33 amIf you're really bored today can you cut off 2 or 3 inches of the jacket so we can see it undisturbed?

author: sdouble
author_rank: Frequent Contributor
timestamp: September 14, 2018, 07:32:20 pm
content: for similar size coax, I'm used to run LMR100A cable. It's doubly shielded, flexible and operate at relatively high frequency (over 1 GHz for sure.) It's also quiet cheap.From time to time I even use chinese clones of the LMR100A like the RFC100A. VERY cheap and very acceptable quality.

author: SeanB
author_rank: Super Contributor
timestamp: September 15, 2018, 06:54:39 am
content: Nice use for that cable is as transmission line antenna along a building. You get good 2 way radio performance all along the cable run.

author: tkamiya
author_rank: Super Contributor
timestamp: September 15, 2018, 09:42:04 pm
content: The cable is now gone. I figured I will never use it.