Content-Transfer-Encoding: 8bit
Message-ID: <3.0.2.32.20000204232500.006ea638@aurora.eexi.gr>
Date: Fri, 04 Feb 2000 23:25:00 +0200
To: rsgb_lf_group@blacksheep.org
From: "Costas Krallis" <sv1xv@eexi.gr>
Subject: Re: LF: Filter capacitors
In-reply-to: <E12GVtv-0004tR-00@sand4.global.net.uk>
References: <17680.200002031444@gemini>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii; format=flowed
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
Sender: <majordom@post.thorcom.com>

At 23:41 03/02/2000 +0000, you wrote:

> I note the comments on faulty filter capacitors with interest. Not 
> certain of details of the transmitter responsible for the "Growler" 
> on 73.3kHz but if it's  a) High powered
>				b) Valved
>				c) Old
>
> then it may well not have any! it not being unknown for them to rely 
> on inductive smoothing (plus "stray" capacity to ground) for the 
> reduction in ripple on HT (11kV+)

As the power is quite high, there is also the possibility of
feeding the power supply from a 3-phase source. In this case
no capacitor is required and an inductive filter is ok, until
one of the rectifiers or one of the 3 phases fail. Then, you
get a 50 Hz component which cannot be filtered easily.

Costas


 +------------------------------------------------------------+
 | Costas Krallis SV1XV      *   LOC KM18UA                   |
 | P.O.Box 3066              *   FAX: +30-1-3811362           |
 | GR-10210 Athens           *   E-Mail: sv1xv@eexi.gr        |
 | GREECE                    *                                |
 +------------------------------------------------------------+