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25 ohms connector or termination for PCB

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flashking

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Hello

I want to buy a 25 ohms termination that can be mounted on a printed circuit board (PCB)

or I want an SMA connector with 25 Ohms impedance

Thanks in advance

Best Regards
 

FvM

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I'm not aware of a 25 ohm connector standard. Using two parallel 50 ohm connector seems a suitable workaround.

You can buy 25 ohm semi-rigid cable, but there's no connector for it, I think.
 

pstuckey

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JFW sells a product called a mismatch load. This is a termination with a non 50 ohm impedance. Normally they create the mismatch by going higher in impedance, but they will go lower on request.

**broken link removed**
 

FvM

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It seems to me that the "mismatched loads" are still using 50 ohm connectors.
 

pstuckey

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It seems to me that the "mismatched loads" are still using 50 ohm connectors.

Yes, that is correct the SMAs are 50 ohm. I've used these in the past to look at transmitter (50 ohm nominal) characteristics when presented with poor VSWR.

Re-reading the original post, I see that I mentally combined his two requests into one though.

As far as surface mount termination, it will depend on the frequency and power you need, but IMS would be a good place to look for either.

**broken link removed**
**broken link removed**

They will do whatever impedance you need, there is minimum order of qty 100 typically.
 

FvM

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The original question isn't completely clear. 25 ohm connector is understandable, but most likely dosen't exist as a standard part. A 25 ohm termination without a connector is just a resistor (or multiple in parallel).
 

flashking

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Thanks for all your help

The original problem was how to measure a matching circuit (matches from 25 to 50 ) ?

the answer was to terminate the 25 ohm side with a "matched" 25 ohm impedance to avoid reflections

so I want a termination, either printed or SMT or IC, that has a load impedance of 25 ohms

Thanks
 

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