Help equested Signal Generator

[john_g]

Hi

Can anyone help? I have a signal generator (SG) and I want to switch, say an SCR at 30 volts at various frequencies powering a coil. How do I connect up the SG to do this and what components should I use so the SG is isolated?

Any help much appreciated.

Regards

John

[Web000x]

You're going to have trouble making an SCR generate any type of signal because of it's on-latching nature. Once you trigger it on, it stays on until the voltage between the anode and the cathode drops to a certain level.

Your best bet is to use a transistor based signal generator and run a multistage amplifier to gain the required voltage. This is usually accomplished by using a 555 timer as the signal and a circuit that can be found here: Multi-stage amplifier : DISCRETE SEMICONDUCTOR CIRCUITS

Basically, you start with the signal and run it into a small transistor which feeds a higher power-rated transistor and so on until the current and voltage are correct for the application at hand.


Dave

[Inquorate]

this should work

15062010493.jpg - Vox

[john_g]

Web00x and Inquorate

Many thanks for your help - that should get me started.

Regards

John

[rave154]

help with func gen

hi all, rather than start a new thread and clog things up i decided to ask my newbie Q here instead,

using my function gen, the output terminal that is marked as "50 Ohm" next to where the BNC cable plugs in.... does this mean that internally the output has a 50 Ohm resistor across the POS and NEG....there fore.....even if i shorted the POS & NEG leads with an amplitude(output) Voltage from the func gen of say 10V ...a max current of only 200mA could flow?

is that correct or am i mistaken( in which case, what does the 50 Ohm refer to?)

thanks

David. D