Message-ID: <200811301109250137.25A352B3@smtp.wanadoo.fr>
In-Reply-To: <200811301105560824.25A024FA@smtp.wanadoo.fr>
References: <002801c7c3ac$17121240$6d188351@w4o8m9>
 <200811281742170811.1CBE4B25@smtp.wanadoo.fr>
 <731EB49F88B309428FFDDD2423F810E441C377@HERMES4.ds.leeds.ac.uk>
 <200811301105560824.25A024FA@smtp.wanadoo.fr>
Date: Sun, 30 Nov 2008 11:09:25 +0100
From: "John RABSON" <john.rabson@wanadoo.fr>
To: rsgb_lf_group@blacksheep.org
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Subject: Re: LF: RE: SDR for 136k / 500k
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That should be 25 x 10000 =B5F.  Stay off the Beaujolais Nouveau.
=20
*********** REPLY SEPARATOR  ***********

On 30/11/2008 at 11:05 John RABSON wrote:

>Chris, Mike,
>
>Many thanks.  I intended to send directly to Jim, but forgot to change the
>To: field.  Yes, the colours are as you describe.
>
>Regarding getting the polarity the wrong way round, in the mid-1960s one
>of my colleagues was called upon to design a power supply with 12 V output
>at some amps.  The output capacitance required was a quarter of Farad made
>up of 25 x 1000 =B5F capacitors connected by busbars.  The prototype came
>back from the workshop and he plugged it in.
>
>At point he realised two things: (1) the workshop had got every one of the
>capacitors wrong way round and (2) the mains switch for his bench was
>located behind the unit under test.  He walked quickly toward the big red
>button at the end of the lab but didn't get there quickly enough.  There
>was a colossal bang and we had a well-decorated ceiling.
>
>73
>John F5VLF
>
>*********** REPLY SEPARATOR  ***********
>
>On 29/11/2008 at 09:12 Chris Trayner wrote:
>
>>Hi John,
>>
>>
>>You saw Jim's reply, but
>>
>>> a grey stripe with a 0 on it and this is adjacent to the shorter of the
>>two leads.  If I recall correctly, this is the negative lead,
>>
>>Is it a rather oval 0?
>>The tradition seems to be a grey minus (rounded rectangle) within a black
>>oval within a grey band on a black background.
>>A case of not quite making up their minds what the colour scheme is? ;-)
>>
>>You may also find some (for want of a better term) crease lines on the
>>exposed metal end of the can. I think these are purposely weak so that if
>>it goes it blows there, with little containment (in the explosives sense).
>>I can vouch for this, as from time to time one of our students puts one
>>wrong way round on the 15V line. They go off with a very satisfying bang!
>>... followed by other students crowding round the bench to see what had
>>happened. The end of the can shears along the crease lines and the bits
>>peel back like petals, allowing fluffy stuff to be ejected fairly
>>harmlessly.
>>
>>73,
>>Clank