[R-390] Rack Mounted R-390A

[Barry]

Let's see...

v^2 = u^2 + 2as

Given s = approximately 1.5 (meters) at shoulder height, v is approximately
5.44 m/s when the radio hits the floor.

kinetic energy = (m * v^2) / 2

An R390A's mass is approximately 36 kg

k = (36 * 5.44^2) / 2 = 532.6848 Joules

How big is the hole in the concrete?

Barry - N4BUQ

----- Original Message ----- 
From: "John Lawson" <jpl15 at panix.com>
To: "Cecil Acuff" <chacuff at cableone.net>
Cc: <r-390 at mailman.qth.net>
Sent: Tuesday, February 07, 2006 10:31 AM
Subject: Re: [R-390] Rack Mounted R-390A


>
>
> On Tue, 7 Feb 2006, Cecil Acuff wrote:
>
> > I've considered designing a small roll around self contained hydraulic
lift
> > to assist in getting them from the floor to the bench....or maybe
> > pneumatic...
> >
> > Would be a great help as one gets older and these radio's get
heavier....
>
>    Actually these are 'items of commerce' and available from most all
> big industrial supply houses.  When I was heavily (yes it's a pun!) into
> collecting vintage minicomputers, I had a mechanical version - used a
> winch and cable.  The smaller, simpler ones look like a 'refrigerator
> dolly' with a small platform or short forks that are used to lift the Item
> Of Interest.
>
>    They're kinda pricey - though they come up for auction from time to
> time.  Just the thing for putting 100+ pound Things in racks, though.
>
>    And yes, I've installed an R-390 at shoulder-height in a rack, myself,
> un-aided. Of course that was damn near 30 years ago - youth is certainly
> wasted on the Young.... and the occasionally stupid....   ;}
>
>    Cheers
>
> John  KB6SCO
>
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