04-30-2023, 01:02 AM
Bouncing Tuners & Flexy Ground Straps
I've poked around with Searches and not found anything definitive on this, so I'll ask here.
My 655's tuner assembly is on soft rubber mounts, presumably for some sort of vibration isolation reason. But really? Why does a tuner need a soft mount?
BTW, tuning anti-vibration mounts for the desired effect is a whole science in itself, and it has to take into account the input vibration (ground motion), the mass and natural frequencies of protected parts, and the stiffness of the mounts. I wonder if these are just off-the-shelf mounts thrown in there just because of some suspicion that they might do something useful?
And regarding the three braided ground straps connecting tuner frame to chassis: There ain't nuthin magical, electrical, RF-ish or Litz-ish about that braid. Just like the ground strap from your car's engine to body, a braid is only used because it can take the flexing that comes from the ends' relative motion without breaking or transmitting mechanical vibration between the connected parts.
Change my mind.
But again- why does the tuner need to move in the first place?
OK, I'll throw out one guess: The mounts don't isolate vibration... instead they allow for thermal expansion of the chassis without stressing the presumably cooler and delicate tuner frame.
In that case, why not achieve grounding via simple looped solid wire? Or even simple stranded wire? Why all the grief of these braids?
I've poked around with Searches and not found anything definitive on this, so I'll ask here.
My 655's tuner assembly is on soft rubber mounts, presumably for some sort of vibration isolation reason. But really? Why does a tuner need a soft mount?
BTW, tuning anti-vibration mounts for the desired effect is a whole science in itself, and it has to take into account the input vibration (ground motion), the mass and natural frequencies of protected parts, and the stiffness of the mounts. I wonder if these are just off-the-shelf mounts thrown in there just because of some suspicion that they might do something useful?
And regarding the three braided ground straps connecting tuner frame to chassis: There ain't nuthin magical, electrical, RF-ish or Litz-ish about that braid. Just like the ground strap from your car's engine to body, a braid is only used because it can take the flexing that comes from the ends' relative motion without breaking or transmitting mechanical vibration between the connected parts.
Change my mind.
But again- why does the tuner need to move in the first place?
OK, I'll throw out one guess: The mounts don't isolate vibration... instead they allow for thermal expansion of the chassis without stressing the presumably cooler and delicate tuner frame.
In that case, why not achieve grounding via simple looped solid wire? Or even simple stranded wire? Why all the grief of these braids?
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