[GreenKeys] Retypes

[Jim Cooper]

On 4 Dec 2021 at 18:11, Tom Hunter wrote:

> I borrowed a page from Harold
> Hallikainen and am using 3-circuit
> loop plugs on everything I would take
> to a school. 

Just to clarify the point you are making here ... 

The "3-circuit loop plugs" are the TRS "tip, ring 
and sleeve" type -- with the loop connections on 
the tip and ring. 

Why do this?  Because with the old 'standard' plug 
it is possible to get a shock from the sleeve of the 
"tip and sleeve" plug (and even the sleeve of the loop 
JACK if it is exposed, such as the long telephone-type 
jacks are) ... and since the usual loop voltage is 100vDC 
that could be quite a shock to a person who accidently 
grabs the plug "the wrong way" ...  and of course especially 
important when demo'ing to kids. 

w2jc