Transformers G1 speaking effect... but how?

Hi all.
I’ve creating a Transformers translation to Hungarian. I’ve got out the audio, discarded the old voices (with the “Karaoke” effect in LADSPA) but I’ve got a problem. In Transformers, the robots have some kind of voice pressing, and I don’t know what’s it’s name or how can I emulate it. Can you help me?
P. S. I never think I find a great sound editor in 3 MB. You’re amazing!

Wikipedia says it’s a vocoder:

I think Wikipedia is correct.

Here’s a Nyquist vocoder plugin, I haven’t used it. Right-click and select “save as…” and put it in your plugins folder:

You’re right. It must named vocoder, since it is.
Tested. Thanks!