Ring modulator in multisim doesnt work as real life (or at all)

[george2525]

Hello

I made a ring modulator which works. I have made the circuit in multisim for some analysis and I get nothing. Im not a fan of multisim but would expect a simple circuit like this to work at least!

The scope shows the carrier but nothing else

Please if anyone could identify something stupid I have done here or is aware of multisim issues with this type of circuit I would be very grateful. Thanks

 

[duke37]

A ring modulator has the diodes chasing their tails. D1 and D2 are connected like a diode rectifying bridge.

 

[Martaine2005]

 

[george2525]

Thanks but its supposed to be unbalanced. I have made it like this and it works but not in multisim

 

[dorke]

George,
As I'm just starting to use Multisim I have used your circuit for a drill,with a small modification( inputs and out,R2 is for measurement ).

It does work in Multisim as you can see below.
You should be careful with the devices you place because the models may be very different,for what seems like a "like symbol".

Notice: the output isn't D.S.B since the carrier is still present.
By flipping D3 vertically you get the true D.S.B desired output.
What is the purpose of not using it balanced?

 

[george2525]

Thanks very much. i will study your circuit later (when kids asleep!) I appreciate the effort and it sounds like what I want.

I want it unbalanced because I use these things for music. Having the carrier simply gives me that tone on the output which I can use as an extra note. i will be processing this later and also have a balanced version. outside of music im not sure why people use the unbalanced ones but I have heard something about use in space programs, though im no expert!

 

[george2525]

im a bit confused about those transformers. Are they standard centre tapped? I cant find those apart from ones that are templates that wont work. Also why did you have to swap the carrier around like that?