Re: Noise from monitor...

["Pigeon" <jah.pigeon@ukonline.co.uk>]

----- Original Message -----
From: <HdV@DTO.TUDelft.NL>
Subject: Re: Noise from monitor...
> Hi,
>
> I had something similar happening on me a couple of years ago. Turned
> out that something called a "cascade" was the cause of those sounds.
> The cascade I am told takes care of frequency-conversion, but I am no
> expert in this field (far from it). The best way to describe it is
> "the device attached to the CRT itself". I was in luck, because a
> friend of mine was able to fix it for me.
>
> Sorry, I can't be more specific, but I hope it will point you in the
> right direction.
>
> Grx HdV
>
> --
> J.A. de Vries aka HdV
> Delft University of Technology
> Computing Centre
>
The "cascade" sounds like another name for the EHT tripler. This is a
sort of "cascade" of diodes and capacitors which converts, not
frequency, but voltage: it multiplies the EHT voltage from the line
output transformer by 3 to supply the CRT, to which it is indeed
directly connected. Its function is to reduce the voltage which the line
output transformer needs to produce. Most sets have it built into the
line output transformer but in some it is a separate unit. The noise is
caused when its internal insulation begins to break down and the EHT
begins to leak, and is usually followed by total failure.

Pigeon