[Elecraft] Line Out Jack

[Josh Fiden]

I'm curious about this. If anyone has reference to an actual 1/8" 
connector, please forward off list. I don't recall them ever being 
anything but 3.5mm. My recollection is that 3.5mm and 1/8" have always 
been used interchangeably. I believe (guess) the discrepancy is simply 
that the plug originated as 3.5mm and 1/8" is the closest fractional 
inch (9/64 is unsatisfying).

Checking specifications from one reputable manufacturer calls out sleeve 
diameter of 3.5+/-0.05mm for the plug and 3.6mm for the entrance of the 
jack. As with so many things, I'm sure there's no difficulty finding 
poorly designed/manufactured Asian parts that deviate.

There's no such issue with 1/4" phone connectors. They are called out 
either as 6.35mm or 6.3mm, which is quite accurate because they 
originated as the fractional inch dimension.

73,
Josh W6XU

On 4/7/2014 7:11 PM, Don Wilhelm wrote:
> 3.5mm and 1/8 inch are now the same thing - one place calls them 3.5mm 
> while others use the 1/8 inch designation for the same thing.
>
> Yes, it was not always so, but that was well before stereo plugs and 
> jacks came into existence.
> The big issue now is manufacturing tolerances that might mean some 
> jack and plug combinations are tight while other combinations may 
> appear to be sloppy.
>
> 1/4 inch plugs and jacks are more tolerant of sloppy tolerances i.e 
> +/- 0.01 mm compared to 3.5mm is much greater than +/- 0.01 mm 
> compared to 7 mm (or is it 8mm?).