[Hallicrafters] AC Bypass Caps

[rbethman]

The "engineering" that put them there is JUST as valid as today's 
engineering!

Roy Morgan has his diatribe for what type to use where, why, and how.

I'm with Carl AND Roy on this one!!

Leave them out if you want to provide a rewind outfit or individual a 
constant source of income.

I'll be using the appropriate caps to REPLACE the ugly mess of yore.

Bob - N0DGN

On 12/13/2010 11:53 AM, Carl wrote:
> That comment makes absolutely no sense.
>
> Carl
> KM1H
>
> ----- Original Message -----
> From: "Asif Khan"<hallicraftersx28 at aol.com>
> To:<Hallicrafters at mailman.qth.net>
> Sent: Monday, December 13, 2010 1:14 AM
> Subject: [Hallicrafters] AC Bypass Caps
>
>
> Everytime I restore  radios  I leave them out . They might been effective
> back in the 1930's and 40's
>
> when the world was less 'noisy' !
> Nick
>
> -----Original Message-----
> From: Glen Zook<gzook at yahoo.com>
> To: Mark K3MSB<mark.k3msb at gmail.com>; List Hallicrafters
> <hallicrafters at mailman.qth.net>; Mike Everette<radiocompass at yahoo.com>
> Sent: Sun, Dec 12, 2010 10:03 pm
> Subject: Re: [Hallicrafters] AC Bypass Caps in SX-111 MK 1.
>
>
> Actually, it really isn't leakage.  Capacitors are supposed to pass AC and
> block
> C.  Therefore, any radio with those capacitors is going to have 1/2 of the
> ains voltage on the chassis.  Of course, with 3 wire cords that voltage is
> rounded out.  It is the same with 2 wire cords when the chassis is
> grounded.
> hat is one of the reasons that the older equipment always had a ground
> terminal
> except for AC/DC which often did not).
> Now when the capacitor does fail, then the full mains voltage and current
> then
> an definitely be on the chassis.  Otherwise, the current is limited
> through the
> apacitor because of the relatively high impedance inherent to the value.
> These days it is questionable as to whether or not to install line bypass
> apacitors, especially in receivers.  In my opinion, leaving them out isn't
> oing to hurt anything.
> Glen, K9STH
> Website:  http://k9sth.com
>
> -- On Sun, 12/12/10, Mike Everette<radiocompass at yahoo.com>  wrote:
> I'm sure some folks will disagree with me... but I would recommend that
> you not
> weat those line bypass caps.  In fact, LEAVE THEM THE HECK OUT.
>
> f they start to leak much at all, you are going to have AC voltage on the
> hassis.  I've seen radios with between 30 and 60 volts AC on them for this
> eason.  That's enough to give you one serious jolt.  And yes, this was due
> to
> ine bypass capacitor leakage... not leakage in the power transformer.  In
> all
> y experience,  which includes ham radio, commercial two-way, avionics, and
> roadcast engineering, I have seen only two power transformers develop
> rimary-to-frame leakage; but PLENTY of leaky line bypass caps.  I damn
> near got
> illed once by a background-music system PA amplifier with a hot chassis
> from a
> eaky cap, when the back of my head touched that chassi as I was reaching
> my
> are and sweaty arm behind a HVAC duct to fish out a speaker lead.
> ha-ZAAAAAAM!  As a result, the very first thing I do when a "new" radio or
> any
> ther device comes into my life is to make REAL sure to take the things out
> of
> t!
>
> remain unconvinced regarding the benefits of having these capacitors in
> the
> adio at all.... except to a funeral director.