[GreenKeys] OT: Explosion-Proof phone on ebay...

[drlegendre .]

Ok, makes better sense. But the question still remains, why must it be so
massive?

Thirty pounds?

How much of what material does it take to encapsulate the otherwise
free-air electrical contacts? I'd think a couple of lip seals, one one the
dial shaft, one on the switch-hook shaft, would fairly well cover it.
Apparently the strategy must be quite a bit more elaborate, but for the
moment, the possibilities escape me.

On Thu, Jan 29, 2015 at 1:50 AM, Jeffrey D Angus <jdangus at att.net> wrote:

> On 1/29/2015 1:14 AM, drlegendre . wrote:
>
>>
>> So in the case of the WE set on eBay, is this phone intended to prevent
>> -or- withstand an explosion - or both?
>>
> Not so much to withstand an explosion, but to prevent one by creating
> an exposed spark in an explosive atmosphere.
>
> The primary concerns would be the rotary dial contacts and the cradle
> (hook) switch, switching the 48 vdc (nominal) phone line voltage.
>
>
>
>
> --
> Jeff-1.0
> wa6fwi
> http://www.foxsmercantile.com
>
>
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