thanks. i've been thinking tranzorbs while reading all this and didn't know who made 'em.
but those stun guns generate about 20kV. is the 30V spec above the voltage they turn on at?
br, mike
- Vote on answer
- posted
20 years ago
HV protection for receiver input?
Loading thread data ...
- Vote on answer
- posted
20 years ago
No.
That's the point.
The transorb will clamp the 20KV to about 30V (actual clamp voltage depends upon the pulse rise time) protecting your circuit.
They have very low capacitance (10 to 15pF) and so should not affect your RF.
Another option is a GDT (gas discharge tube), even lower capacitance (only a couple of pF) and can be purchased in as low as 90V DC clamping voltages.
See:
formatting link
- Vote on answer
- posted
20 years ago
sorry, I meant "the above 30V spec", not the "30V spec above" :-) i should have just left the "a" word out, but after a few days, it appears my grammatical error elicited a response.
hey. those GDTs are used to protect CATV amp ins/outs. those amps aren't cheap, so there must be something there. lower cost (?) and lower capacitance.
mike
formatting link
- Vote on answer
- posted
20 years ago
The CATV systems I worked on required the gas discharge tubes to be replaced as preventative maintenance, due to the tubes degrading slightly with each activation.
- Vote on answer
- posted
20 years ago
hi cable dog:
i can see that happening. i just built and activated the systems. line gear maint was for in house. design, new/rebuild, retro, some sweep, make-ready... i did it.
brs, mike