[Amps] Ouch - 23 Ohms ?

[Dan Sawyer]

Thank you. The devices are Mini-Circuits ZFDC-20-5-23. Normally these 
devices either have no third numeric indicating 50 Ohms, or a 75 
indicating 75 Ohms.

I am trying to determine both the coupler impedance and the device pass 
through impedance. I believe the coupler impedance is 23 Ohms as that is 
what is measured with a DVM. I will try to measure reflection with a 
variable resistor.

Dave Bowker wrote:

>Dan,
>
>No it will not as long as the termination Ohms is 50 ± j0 at the frequency you are measuring phase 
>at.  Depending upon the design of the coupler, the lack of proper terminations [could] affect phase. 
>If you provide the mfg and P/N I probably can be of better assistance.
>
>Dave
>
>
>I am only interested on phase. I am using these as pickups to feed an
>8405a vector volt meter. Will the termination effect the phase? I don't
>see how, but on that note I have a good understanding of how these work.
>
>Dave Bowker wrote:
>
>  
>
>>Dan,
>>
>>You MUST terminate the ports in their design impedance, typically 50 Ohms, when measuring!
>>
>>73, Dave, K1FK
>>Fort Kent, ME
>>
>>
>>
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