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Banggood 50 ohm BNC feed-through terminator - a quick review
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rf-loop:
How it looks when terminator other end is connected to ecample 1M/18pF real scope input.  How scope internal circuit see it and how external signal see it when this spaghetti circuit say hello to coming signal. Also we need care higher frequencies even if scilloscope nameplate freq BW is 200MHz. Many times these may have real -3dB point far over 200MHz and many times -6db well over 300 or even 400. With fast risetime signals we then can see all wonderland miracles what we have seen in many places and in this forum many times.  Terminator itself may be more or less ok but is measurenment system ok if yhink 50 ohm termination. I have seen so much terrible and horrible results, also in my self made tests. Best what I have seen was in some old HP digital oscilloscope internal 50 ohm termination what can say it is 50 ohm impedance over wide freq range. Real RF guys developed and designed. Very very different what we can see in cheap oscilloscopes where these 50ohm input are just like 50ohm  DC/audio loading resistors.

But, how is feed thru terminator connected to oscilloscope input spaghetti circuit.
50 ohm terminator connected to scope input using T is more bad. Acceptable with DC and LF but also bit higher if measurement quality is first what can push to garbage collection. Still can see wonderland images.
SeanB:
150R reel was less than half the price of the 100R reel that morning. so they used that, despite needing an extra resistor to make up the right value. Hate to think of the guy who gets the change over ones, with either resistor value being used and either 2 or 3 as well.
BravoV:
So how can we improve this terminator say just desolder all the current resistors, and then probably replace with new and better ones, better placement of the resistors and etc ?

Or there is not so much to expect from this BNC metal bodies to make a good terminator say up to 500 MHz ? or even 1 GHz ?

Actually I've been thinking to order more and make myself various attenuators.  :P
Specmaster:

--- Quote from: TheSteve on July 07, 2017, 02:54:46 am ---I did a quick check with a DMM and found one was near 50 ohms, the other though is 100 ohms - so quality control may be an issue.

--- End quote ---
Even so, 100 ohms is way better than 1,000,000 ohms :-DD
Diabolo:
Hello,

2 resistors 1/4W of 100 ohms in // give 1/2W of "power", 3 resistors 1/4W of 150 ohms give 3/4 W of "power" !

Diabolo
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