I don't have a lot of electronics experience and thank you in advance for your assistance. I would like to make a set of relays that when 12 volts is applied they buzz or chatter at high frequency. I will use these paired relays to test another product to see how the interference from these relays affect the performance of the other product. I think you can tie 2 standard automotive relays together but I have no idea what poles get connected to each other and then which pole gets +12 and -12 volt. Any help is greatly appreciated.

 

Relays are generally not polarized. any coil terminal can go to ground and the other to +12.

What is the effect you are investigating? High speed and relays is a relative term - you may not get then operating above a few Hz. If it is the EMI from a collapsing field you need, then a 12 volt buzzer may operate faster. Using a FET to switch current through a solenoid can get significantly faster than that.

 

Yes, I am trying to make something that has a high frequency buzz (simulated interference) that I can use to make a cheap bench test to simulate noise on a 12 volt power line as well as EMI. Thank you for your help.

 

A SPST(NC) or a SPDT (more common) relay can be made to buzz. Though relays can't really buzz at very high frequencies there is a high frequency component there when the contacts open. The longer the wires are the more energy they will radiate. Probably not the most efficient noise generator though but it will work.

 

CDRIVE thank you for the schematic. The chatter relay is supposed to be 2 relays seems one open and the other closes and it is a repititive rather high frequency cycle. I think it is a crude way to make noise as well as some EMF. I then will use on a bench test just as a go no go test for interference handling of some auto parts.
Thanks you,
Mark

 

CDRIVE thank you for the schematic. The chatter relay is supposed to be 2 relays.....
Mark

May I ask why, as it would seem redundant. You also need to specify whether you are trying to inject this noise into the power supply lines or through airborne radiation. Hey, that statement is redundant too!