# frequency mixing : ~ns electrical pulse at 100kHz + 400MHz RF sinusoidal wave

Discussion in 'Electronic Basics' started by Q-man, Nov 27, 2004.

1. ### Q-manGuest

I would like to mix two electrical waves. One is ~ns electrical pulse
at 100kHz and other is a 400MHz RF sinusoial wave.

Would you please recommend any device which can mix two waves?

I've heard that a GaAs SPDT switch or frequency mixer can do this kind
of job.
If you know how to use this kind of device, would you tell me the
instruction of the operation?

Thanks.

3. ### dBGuest

(Q-man) wrote

A diode. It's the simplest mixer there is.

4. ### ddwyerGuest

Mixing is multiplication so that you wish to multiply the 400MHz sine
with 0 or 1 at 100kHz . A switch can be used the The limits are how
perfect the switch can be.
Minicircuits double balances mixers would be as good as any solution.

5. ### Q-manGuest

I would like to mix two electrical sources. One is ~ns electrical
pulse at 100kHz and the other is 400MHz RF sinusoidal wave.

I think there is a problem to use the frequency mixer to combine two
signals.
It is because the nsec electrial pulse at 100kHz has a DC component. I
cannot find any frequency mixer has DC output from IF port.

May I hear your opinion ?

6. ### Q-manGuest

sorry for making a mistake. This is a correction.

It is because the nsec electrial pulse at 100kHz has a DC component. I
cannot find any frequency mixer has "DC input" from either RF or LO port.

7. ### John LarkinGuest

Actually, the DC component will be very small if the duty cycle is
nanoseconds per 10 microseconds. Still, ring diode mixers will let a
lot of signal through with zero LO input.

Fairchild has a bunch of interesting analog switches...

http://www.fairchildsemi.com/parame...:3//Function//:in//Analog+Switch,Video+Switch

John

8. ### Q-manGuest

That's right. If duty cycle is getting smaller, that effect will be
minimized.

By the way, I would like to try to use the SPDT switch to generate the
mixed signals. I contact the Minicircuit but it is hard to understand
how to use.
If you know how to use this switch, would you please tell me ? There
are five ports in this switch. RF in, control ports 1 and 2, RF out 1
and 2. Especially i am confused about control ports.

model : ZFSW-2-46
http://www.minicircuits.com/dg03-218.pdf

Thanks.