At 11:38 AM 2009-07-14, Michael Biel wrote:
>I found specs for a .206 plug with a trademarked name Littel-plug and
>Littel-jax,
Those are Switchcraft Trademarks and have been since at least the
1950s when I first started reading Allied Radio catalogs.
>I also remembered this morning that Wollensak and some Revere
>tape recorders used a quarter inch T-R-S jack as a mono input with the
>tip for line level and the ring for mic level. Their microphones had
>short plugs on them that would have its tip hit the ring in the jack.
>Replacement plugs were very hard to find, so if you used a regular phone
>plug you had to put it in part way.
While I never tried this on my Wollensak T-1616, it did have this
plug. Wouldn't wiring a standard plug Ring-Sleeve and leaving the Tip
open do the trick, or was there a switch on the tip spring that got activated?
> > It seems to me that the 1/8" and 1/16" sizes were converted
> > from that size. It would them be historically correct to
> > call them that, using the metric dimensions to several significant
> > figures only for their manufacture in metric countries. Failure
> > to do thus may be why I often find 1/8" phone plugs that will
> > not fit into the 3.5 mm jacks found on some Chinese audio equipment.
Switchcraft interestingly has some tolerances built into some of
their designations.
http://www.switchcraft.com/products/jack-search.html
Their "Bantam" (aka "Tiny Telephone") pro patch plugs are listed as
0.173, but they also have a 0.177 jack (huh?)
Switchcraft also offers 0.141 and 3.5 mm jacks on the same page and
0.101" subminiature ones as well. 3.5 mm converts to 0.138 not 0.141.
Also 0.101 converts to 2.57 mm, not 2.5 mm.
>I noted this morning a Wikipedia article (confirming that Wikipedia is
>NOT a reliable source -- NEVER USE IT) that cited the RCA plug as also
>being called the Cinch plug. There is a manufacturer of a wide variety
>of square and rectangular multi-pin connectors called Cinch-Jones. Just
>because some guy called the RCA plug Cinch once doesn't make it so!
Actually, my understanding is that the above quote from Wikipedia IS
CORRECT. In Europe, "Cinch" is widely used to refer to what we call
"RCA" jacks.
>The first AEG Magnetophon, model K-2, ran at one meter per second.
>These machines had capstans that were 13mm in diameter. The speed was
>reduced by AEG to 30 inches per second around 1937 or 38. These
>machines had capstans 10mm in diameter. When I was told this
>distinction by Friedrich Engel I measured the capstan on my K-2 serial
>number 1025 at his request. It was 13mm, so I have a one meter per
>second machine, but all of the machines eventually used by German radio
>during WW II ran at 30 inches per second. So it was the German's who
>changed the speed to English measure, and the postwar reductions to
>fractions of it were based on their pre-war choice of 30 IPS in English
>measure.
Is that really true? I know the first part is true as Herr Engel and
I have discussed this as well, but if we assume that a 13 mm diameter
shaft gives us 1 m/s then wouldn't a 10 mm diameter shaft give us
10/13 m/s? That is approximately 30.3 in/s. I had always heard that
the 10 mm diameter capstans were not 30.000 in/s, but rather about 77
cm/s. (770 mm/s if you will).
>The nearby metric-based identifications are only
>identifications. The actual speeds on machines made in metric countries
>are still English measure of 15.000 IPS, 7.500 IPS 3.750 IPS, 1.875 IPS
>etc.
That is correct as far as I understand it post-Magnetophon.
Cheers,
Richard
Richard L. Hess email: [log in to unmask]
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.
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