ampage Tube Amps / Music Electronics	For current discussions, please visit Music Electronics Forum.

ampage archive

Vintage threads from the first ten years

previous: Dave H I prefer air insulated wire to Tefl... -- 8/17/2004 2:04 PM

Re: Lacquer covered cloth wire over PVC insulation?

8/17/2004 8:29 PM
Mick	Re: Lacquer covered cloth wire over PVC insulation? Actually, to add to Bruce's point about the shunt capacitance in type RG-58 50 ohm coaxial transmission line, that capacitance serves a very specific purpose. It is there to resonate out the series inductance induced by the center conductor. The net result is that the transmission line looks purely resistive in a 50 ohm system with no reactive (capacitive or inductive) component leftover. At RF frequencies, this is critical to providing optimum power transfer between stages (i.e. a power amplifier and an antenna). So in this particular case, you'd better have that shunt capacitance there or the net result would be power loss. What does all of this have to do with stray capacitance? Absolutely nothing. I would be more concerned about mechanical vibrations caused by teflon or PVC wiring contacting the chassis when you've got your amp up on 10. For this reason alone, I'll stick with cloth wire. Mick

8/17/2004 8:29 PM

Mick

Re: Lacquer covered cloth wire over PVC insulation?

Actually, to add to Bruce's point about the shunt capacitance in type RG-58 50 ohm coaxial transmission line, that capacitance serves a very specific purpose. It is there to resonate out the series inductance induced by the center conductor. The net result is that the transmission line looks purely resistive in a 50 ohm system with no reactive (capacitive or inductive) component leftover. At RF frequencies, this is critical to providing optimum power transfer between stages (i.e. a power amplifier and an antenna). So in this particular case, you'd better have that shunt capacitance there or the net result would be power loss.

What does all of this have to do with stray capacitance? Absolutely nothing. I would be more concerned about mechanical vibrations caused by teflon or PVC wiring contacting the chassis when you've got your amp up on 10. For this reason alone, I'll stick with cloth wire.

Mick

Replies:

Wild Bill Mick, you shouldn't have reminded u... -- 8/17/2004 11:16 PM