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Products => Test Equipment => Topic started by: mzzj on April 06, 2018, 09:45:12 am

Title: Chinese (Reichelt.de) feed-trough BNC terminator
Post by: mzzj on April 06, 2018, 09:45:12 am
Was playing along with these and diy cable TDR. These were quite ugly compared to better terminators so I decided to take a look inside:
(https://i.imgur.com/2Mzkvkwh.jpg)
Title: Re: Chinese (Reichelt.de) feed-trough BNC terminator
Post by: BravoV on April 06, 2018, 09:53:43 am
Was playing along with these and diy cable TDR. These were quite ugly compared to better terminators so I decided to take a look inside:

(https://www.eevblog.com/forum/testgear/banggood-50-ohm-bnc-feed-through-terminator-a-quick-review/?action=dlattach;attach=329772;image)

(https://www.eevblog.com/forum/testgear/banggood-50-ohm-bnc-feed-through-terminator-a-quick-review/?action=dlattach;attach=329757;image)
Click to enlarge photo.

Indeed, even the Banggood or Aliexpress cheapos are better in terms of construction, reviewed -> HERE (https://www.eevblog.com/forum/testgear/banggood-50-ohm-bnc-feed-through-terminator-a-quick-review/)
Title: Re: Chinese (Reichelt.de) feed-trough BNC terminator
Post by: mzzj on April 06, 2018, 10:19:00 am
This homebrew was couple of orders better:
(https://i.imgur.com/p9de7A9h.jpg)
Title: Re: Chinese (Reichelt.de) feed-trough BNC terminator
Post by: ebastler on April 06, 2018, 11:29:17 am
Was playing along with these and diy cable TDR. These were quite ugly compared to better terminators so I decided to take a look inside:

That was a rather thorough "look inside". :)
Thanks for the photo!
Title: Re: Chinese (Reichelt.de) feed-trough BNC terminator
Post by: paschulke2 on April 06, 2018, 11:55:46 am
I once was tempted to buy this terminator from Reichelt because it is much cheaper than a Pomona 4119-50. I did not buy it because i did not like its length (it's an invitation to break the BNC jacks of your scope) and because I thought i was too cheap. Seems I was right …

Now if someone could please cut open a Pomona 4119-50 …
Title: Re: Chinese (Reichelt.de) feed-trough BNC terminator
Post by: tkamiya on April 08, 2018, 02:27:19 pm
Wow....  the original picture is not even a "feed through" as there is no connection between center pins.  I guess that short wire is a "radiator" and pin on the other side is the "receiver?"

Similar story.  I took apart a cheapo Chinese made 50 ohm terminator.  Ground side was not firmly attached anywhere but it was a "press fit" by folding the wire back and shoving it on a tube.  Amazingly, it worked ok for 1.5Ghz.
Title: Re: Chinese (Reichelt.de) feed-trough BNC terminator
Post by: Twoflower on April 08, 2018, 02:56:22 pm
That missing feed-through came up to my mind as well. But if you look closely there is a bluish wire running left of the resistor. It ends in the middle of nowhere about in the middle of the resistor. So I assume the cut was cutting also the wire and the center connector at the lower connector.
Title: Re: Chinese (Reichelt.de) feed-trough BNC terminator
Post by: Ringmodulator on April 10, 2018, 06:07:37 pm
I had also bought one of those from reichelt.de some years ago. If I remember correct, they were even specced for 1GHz bach then :palm:
As I checked this one, it turned out to be good up to maybe 30MHz.

I have built way cheaper ones with a BNC plug and socket like on the picture above from BravoV.
The caveat with those is the low power rating for the SMD resistor(s).