Signal Generator output at 50ohms or 600hms?

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Whoops

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Hi,
I'm calibrating an Urei 1178 unit.

I'm new to calibrating gear. I bought a signal generator and the output impedance is switchable between 50ohm or 600ohm.

For the 1178 I need to send to it's input an 1K sine wave at 0.775V

For this task should I use the signal generator switch to terminate it's output at 50ohms or 600ohms?

Thank you so much
 
Whoops said:
For the 1178 I need to send to it's input an 1K sine wave at 0.775V
For this task should I use the signal generator switch to terminate it's output at 50ohms or 600 ohms?
1178 input impedance is 20k balanced,  10k unbalanced.
matters little if your generator is 50 or 600 ohms,
50 ohms might be a bit more "real world".
the generator need not be terminated,
am presuming you meant selecting  generator source impedance.
 
Thank you so much Gridcurrent

gridcurrent said:
am presuming you meant selecting  generator source impedance.

I though it was the Generator "Output Impedance", last button on the right,
am I wrong or maybe using the wrong words?

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It would depend on the generator and also the input impedance of the 1178. A lot of pro generators are designed for matched impedance.  So if you're driving 50 ohms,  you set the generator to 50 ohms as well and the voltages would be correct.  If you would then measure the output unloaded the voltage would be double what the generator says.

So you really need to know the details of both the generator and the 1178. As a practical matter I would just hook it up and adjust and measure until you get the right voltage driving the 1178.
 
john12ax7 said:
So you really need to know the details of both the generator and the 1178. As a practical matter I would just hook it up and adjust and measure until you get the right voltage driving the 1178.

Well in this case it's just 2 options on the Signal Generator 50r or 600r.

I will go with the switch in the 50r position like gridcurrent sugested

thanks
 
Whoops said:
Well in this case it's just 2 options on the Signal Generator 50r or 600r.

I will go with the switch in the 50r position like gridcurrent sugested

thanks

I agree, 50 would be the better the default setting.
 

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