Author Topic: This was not what I expected  (Read 4729 times)

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Offline DrMagTopic starter

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This was not what I expected
« on: September 19, 2017, 03:38:52 am »
I need a BNC to UHF adapter to try out an antenna I just purchased; the only radio I have right now has a BNC connector for the antenna, and the antenna has an SO-239 connector. I happened to be making a purchase on Amazon, and found a listing for two adapters of exactly what I needed. The product photo looks like this:


The package arrived today, and what I actually got was this:


Now aside from the obvious perils of purchasing from unknown Chinese sources, I do have to ask---what on earth is this thing even for?!?! Note that this is *not* an SMA to RP-SMA adapter; one end is SMA-male (with a pin), and the other SMA-female (without a pin). This part is quite possibly the shortest SMA extension in the world.

So what say you; is there a reason this part was ever even fabricated?
 

Online helius

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Re: This was not what I expected
« Reply #1 on: September 19, 2017, 03:50:37 am »
That is a connector saver, for situations when the cable is repeatedly plugged and unplugged.
 
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Offline Brumby

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Re: This was not what I expected
« Reply #2 on: September 19, 2017, 04:51:46 am »
That's a fail.

I'm curious though .... what's on the sticker under the one we can read?
Why Clippy?  --> https://www.youtube.com/watch?v=2_Dtmpe9qaQ
 

Offline bjcuizon

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Re: This was not what I expected
« Reply #3 on: September 19, 2017, 06:53:59 am »
Beware of these connectors  from China. Sometimes, the really "gold" & shiny ones are fake ones because they want it to stand out over the real ones which normally have some minor scratches on the surface.
« Last Edit: September 19, 2017, 06:56:16 am by bjcuizon »
 

Offline DrMagTopic starter

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Re: This was not what I expected
« Reply #4 on: September 19, 2017, 06:58:06 am »
I was curious too.


Not much help there... but it does look like a label got slapped onto another product. I suppose it's good I ordered it on Amazon; returning and refunding is a breeze.
 

Offline bd139

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Re: This was not what I expected
« Reply #5 on: September 19, 2017, 08:50:14 am »
I've got to the point I only ever order anything on Amazon that's actually sold by them. I've had so many problems with marketplace sellers, even fulfilled by amazon. Total minefield.
 
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Offline macboy

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Re: This was not what I expected
« Reply #6 on: September 19, 2017, 01:48:18 pm »
That is a connector saver, for situations when the cable is repeatedly plugged and unplugged.
But it fails badly at that too. Note how the nut doesn't swivel? You twist the entire connector (including center pin) onto the mating female connector you are trying to "save". The pin rotating down into the socket causes very significant undue wear, equivalent to many "proper" mating cycles.
 

Offline Joel_l

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Re: This was not what I expected
« Reply #7 on: September 19, 2017, 02:38:21 pm »
Is it one of the SMA to SMA RP I think adapters. Changes the sex of the pin/socket. Would have a pin on both sides or a socket on both sides.
« Last Edit: September 19, 2017, 02:40:11 pm by Joel_l »
 

Offline dmills

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Re: This was not what I expected
« Reply #8 on: September 19, 2017, 02:44:24 pm »
Sometimes, the really "gold" & shiny ones are fake ones because they want it to stand out over the real ones which normally have some minor scratches on the surface.
Yep, bright, shiny, and very slightly the wrong thread pitch or pin diameter, been there, done that.

Connectors are enough of a minefield these days that just buying from Rosenburger/Huber & Schurner/MA-COM becomes increasingly attractive.

Regards, Dan.
 

Offline DrMagTopic starter

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Re: This was not what I expected
« Reply #9 on: September 19, 2017, 03:48:47 pm »
Is it one of the SMA to SMA RP I think adapters. Changes the sex of the pin/socket. Would have a pin on both sides or a socket on both sides.

As above, no; it has a pin on the male side and a hole on the female side. Just a normal SMA connector.

That is a connector saver, for situations when the cable is repeatedly plugged and unplugged.
But it fails badly at that too. Note how the nut doesn't swivel? You twist the entire connector (including center pin) onto the mating female connector you are trying to "save". The pin rotating down into the socket causes very significant undue wear, equivalent to many "proper" mating cycles.

Looking up connector savers, that is indeed what this part is. It actually does swivel, though the photo I took certainly makes it look otherwise. Still, the utility of a $5 to increase the life of your $5 connector seems less than ideal. If I were building something that would require the use of one of these, I would seriously reconsider the connector I'm using to begin with.
 

Offline tooki

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Re: This was not what I expected
« Reply #10 on: September 19, 2017, 05:35:22 pm »
I've got to the point I only ever order anything on Amazon that's actually sold by them. I've had so many problems with marketplace sellers, even fulfilled by amazon. Total minefield.
What really, really sucks is that Amazon pools its own stock with that of the FbA sellers, meaning that a FbA marketplace seller can inadvertently or knowlingly contaminate Amazon's own inventory of an item.

This is why a year ago, Apple sued a vendor of counterfeit accessories (like USB chargers) on Amazon -- customers were ordering from Amazon itself, paying full price and expecting genuine product, and receiving counterfeit. When Apple then ordered 100 "genuine" chargers from FbA sellers, 90% of the chargers received (!) were counterfeit. In both instances, the fake product was what FbA sellers had supplied and fed into Amazon's inventory as "genuine", and in this case, Amazon was able to identify the culpable seller, which is why Apple was able to sue it.

I wanna say that Amazon has itself stopped selling Apple USB chargers, as you cannot find them for sale from Amazon itself at all. (For example, search for "Apple 12W USB power adapter" -- there are no exact hits with Prime shipping, meaning that Amazon isn't selling it.)

Samsung has had the same issues, as I understand it.

For anything like chargers or batteries, it's better to buy directly from the manufacturer, even if it costs more. (Or buy a known-decent third party like Belkin or Anker. At least for now, those are unlikely to be victims of counterfeiting.)
« Last Edit: September 19, 2017, 05:38:02 pm by tooki »
 

Offline bd139

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Re: This was not what I expected
« Reply #11 on: September 19, 2017, 05:44:46 pm »
I had no idea they pooled stock. You'd expect them to use a distinct SKU and inventory location. That's just shit. I'm cancelling my prime sub on that basis. Fuck 'em.

I deal with their AWS compute infrastructure as well on a daily basis and that's McDonald's computing as well. Total PITA.
 

Online helius

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Re: This was not what I expected
« Reply #12 on: September 19, 2017, 06:49:25 pm »
Looking up connector savers, that is indeed what this part is. It actually does swivel, though the photo I took certainly makes it look otherwise. Still, the utility of a $5 to increase the life of your $5 connector seems less than ideal. If I were building something that would require the use of one of these, I would seriously reconsider the connector I'm using to begin with.
They are used more frequently the more precise the connector is. Not only to protect from accidents like mis-threading the cable plug, but because they effectively square the lifetime of the original connector. So if the connector on your network analyzer is rated for 500 cycles, using a connector saver of the same type and grade makes it effectively 250,000 cycles (after 500 cycles, replace the connector saver with a new one, and repeat 500 times).
 
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Offline Mechatrommer

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Re: This was not what I expected
« Reply #13 on: September 20, 2017, 03:19:38 am »
I need a BNC to UHF adapter to try out an antenna I just purchased; the only radio I have right now has a BNC connector for the antenna, and the antenna has an SO-239 connector. I happened to be making a purchase on Amazon, and found a listing for two adapters of exactly what I needed. The product photo looks like this:


The package arrived today, and what I actually got was this:


Now aside from the obvious perils of purchasing from unknown Chinese sources, I do have to ask---what on earth is this thing even for?!?! Note that this is *not* an SMA to RP-SMA adapter; one end is SMA-male (with a pin), and the other SMA-female (without a pin). This part is quite possibly the shortest SMA extension in the world.

So what say you; is there a reason this part was ever even fabricated?
if buy from ebay i got wrong item i can force seller to refund in paypal, or if time permit, resend the correct item at no cost..


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