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RG400?

Duhg

Well Known Member
Are there different grades or qualities of RG400? Is the RG400 on Amazon the same quality as the stuff at Spruce? They look the same and are both double braid shielded. Spruce is certified and $100 more for 40'.
 
I wouldn't trust Amazon for anything that you don't want to do over......:eek:

Know the supplier and the brand.
 
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There are documented specifications for most things, including coax cable, and certainly RG400. But just because the printed information on the cable says it is RG400 doesn't mean it is RG400. Unscrupulous manufacturers will sell anything. Buy your materials from a reputable supplier to get what you really want.
 
I personally don’t feel quite so negative on this as the other posters. Sure, the stuff might be junk, but it’s not a given. If time is not a huge issue, I would be tempted to buy a small quantity of it, dissect it and compare against some good stuff,and perhaps try it out without doing a full install. It’s not like your plane is gonna fall out of the sky with it. Your call.
 
RG400

Yes there are different types off RG400 sold.
I have come across the good and the bad types.
The difference in my case was the inner wire was solid.
It is not suitable for use in aircraft.
This should be stranded wire.
They look the same so it is easy to make a mistake.

Good Luck
 
Yes there are different types off RG400 sold.
I have come across the good and the bad types.
The difference in my case was the inner wire was solid.
It is not suitable for use in aircraft.
This should be stranded wire.
They look the same so it is easy to make a mistake.

Good Luck

You should have asked for a refund. The cable you got did not conform to RG400 specifications, which call for stranded wire.
 
Search counterfeit coaxial cable, the number of hits that come up indicates this is a wide spread problem.
I suggest buying RG-400 from a reputable dealer such as Stein.
Use good construction practices, quality connectors, and proper routing and it will be trouble free for the life of the aircraft.
 
Seems Amazon is 1/2 the price then the airplane guys. So the question is how much risk of having to debug/redo it do you want to take on for 30$ (you won’t need a lot).

In general my experience with Amazon is pretty good in terms of counterfeit stuff. In particular with stores which have a lot of reviews. Ebay on the other hand …. .

Oliver
 
I wonder if that solid conductor coax wasn't RG-142? It looks very similar to RG-400.

At 1090Mhz, RG-142 has a slightly lower insertion loss than RG-400, on a typical length of run. And, part of the reason is that the center conductor is solid. But, that makes it less flexible than RG-400. It is also much more expensive than RG-400.
 
Yes there are different types off RG400 sold.
I have come across the good and the bad types.
The difference in my case was the inner wire was solid.
It is not suitable for use in aircraft.
This should be stranded wire.
They look the same so it is easy to make a mistake.

Good Luck

What you got there was RG142B. It's actually more expensive and has slightly less loss than RG400. It is suitable for aircraft. Most avionics manufacturers allow RG142B and many used to specify it prior to RG400 becoming the norm. Because of the solid center conductor of RG400 it cannot take much of a bend so it is not as desirable for long runs that have to make turns. That's why everybody uses RG400 now.
 
The Amazon stuff is $95 cheaper for 40' than Spruce. It specifies a manufacturer and the exact same specs (multi strand same size and strand count) as Spruce. Spruce doesn't show a manufacturer. I'm NOT knocking Spruce, I'm simply asking if there's a difference in specs for "RG400". I'm not afraid to spend $100 for quality and reliability. I feel like a dork spending $100 extra for the same product. I HATE to support Amazon, and as a retail/website owner I want to support small business but feel like an idiot spending in excess of 50% higher prices for the same product. I feel like a koolaid drinker blowing an extra $100 for 40' of wire IF it's the exact same stuff.

What I did: I ordered 35' of RG400 cable, various BNC and TNC connectors, bolts, thread witness, and 1/4 turn fasteners from Spruce and Stein.

I truly appreciate your advice :)
 
It may well be that Amazon has descent quality cable at a lower price, from a wholesale vendor that buys 1000’ at a time. But IMHO there is a wide variation in the quality of the connectors.
 
If the Amazon stuff states that it is MIL-DTL-17 (or MIL-C-17) spec RG400, then it is aircraft grade coax cable. It'll have something like M17/128 RG-400 printed on the outer insulation.
 
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If the Amazon stuff states that it is MIL-DTL-17 (or MIL-C-17) spec RG400, then it is aircraft grade coax cable. It'll have something like M17/128 RG-400 printed on the outer insulation.

Bull. A lot of the stuff sold by Amazon is counterfeit from China. Just because it is marked appropriately does not mean its the real deal. Just ask anybody who works for U.S. Customs. Pay a little more and buy your stuff from a reputable dealer.
 
Bull. A lot of the stuff sold by Amazon is counterfeit from China. Just because it is marked appropriately does not mean its the real deal. Just ask anybody who works for U.S. Customs. Pay a little more and buy your stuff from a reputable dealer.

I really wouldn't generalize like that.

- I have never seen a counterfeit item sold by Amazon itself (they list the sold by on the right side of the screen and only when it says sold by Amazon Amazon is the actual seller). If you have an example please point me to it. Amazon is way to big of a litigation target to risk anything in that space.

- If you pick an item on Amazon which is sold by a 3rd party seller and Amazon only provides the store front and logistics looking at the reviews and a bit more at the details of the seller is critical. There are stores on their which are as reputable as any of the once you mentioned if not more. E.g. I clean my RV with AeroCosmetic products and the manufacturer has a store front on Amazon but also resell through Aircraft Spruce. Why wouldn't I buy that on Amazon with quicker/cheaper (free one day) shipping? There are also stores on their I wouldn't buy anything from.

So I am not sure how you come up with the generalization above.

Oliver
 
I really wouldn't generalize like that.

- I have never seen a counterfeit item sold by Amazon itself (they list the sold by on the right side of the screen and only when it says sold by Amazon Amazon is the actual seller). If you have an example please point me to it. Amazon is way to big of a litigation target to risk anything in that space.

- If you pick an item on Amazon which is sold by a 3rd party seller and Amazon only provides the store front and logistics looking at the reviews and a bit more at the details of the seller is critical. There are stores on their which are as reputable as any of the once you mentioned if not more. E.g. I clean my RV with AeroCosmetic products and the manufacturer has a store front on Amazon but also resell through Aircraft Spruce. Why wouldn't I buy that on Amazon with quicker/cheaper (free one day) shipping? There are also stores on their I wouldn't buy anything from.

So I am not sure how you come up with the generalization above.

Oliver

agreed.

Also there is a big difference between counterfeit and knock off or copied products. RG400 is a standard not a brand, therefore, ANYONE who makes RG400 cable, even if they don't follow the specification is NOT a counterfeit; Just a deceitful seller. Counterfeit, by definition is making an identical product and putting someone else's brand name on it. Counterfeit is synonymous with trademark infringement. I do agree that you should expect significant differences in quality of a product like RG400 cable and there is more safety in buying from sellers that seek out higher quality vs price or buying branded cable from a mfg you trust.

Amazon sells A LOT of knock off products (perfectly legal and ethical, assuming no patent is in place), but does a pretty good job of trying, and I emphasize trying, to keep counterfeit products off their site. Products sold by smaller amazon partners are much more likely to be counterfeit than those sold by amazon directly and I doubt there are more than a handful of counterfeit products sold by Amazon directly. That is a serious risk for them.

Larry
Larry
 
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Bull. A lot of the stuff sold by Amazon is counterfeit from China. Just because it is marked appropriately does not mean its the real deal. Just ask anybody who works for U.S. Customs. Pay a little more and buy your stuff from a reputable dealer.

Obviously, buy a small quantity and check it out before putting it on the airplane. I have, and was satisfied the RG-400 I bought from Shenzen/Eightwood (Amazon storefront) is the real deal.

The counterfeit stuff is really easy to spot. Silver plated copper double braid is a pretty expensive knock off, not worth the effort to make a passable counterfeit.

Then there's "Operation Wing Span". The FBI is going after Mil-Spec counterfeiters, and selling on Amazon would be low-hanging fruit.
 
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