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Hi,

Would anyone know the apropriate value to used on the main switch
(volume & main switch) of the quad 33 preamp. I am replacing the on-
off & volume switch on such a unit . The part I am replacing has no
suppressor cap on it. I have a few 250 V small square film capacitors
(4700pF...up to 1 uF Siemen and RIFA @ 250V) on hand.

Thank you in advance

[Serge Auckland[_2_]]

wrote in message
...
Hi,

Would anyone know the apropriate value to used on the main switch
(volume & main switch) of the quad 33 preamp. I am replacing the on-
off & volume switch on such a unit . The part I am replacing has no
suppressor cap on it. I have a few 250 V small square film capacitors
(4700pF...up to 1 uF Siemen and RIFA @ 250V) on hand.

Thank you in advance

QUAD didn't fit suppressor caps on the 33 or 44 (don't know about the 34),
but if you think one is necessary, I would use 0.1microfarad (100nF). 250v
is too low however to go across 220-240v mains. I would select a 450v part.
If you are in a 110 volt country, then 250v is OK, but I would still prefer
a 450v part in case you should ever sell the 33 to a European, or it ever
gets over here.

S.

--
http://audiopages.googlepages.com

[Dave Platt]

In article ,
Serge Auckland wrote:

QUAD didn't fit suppressor caps on the 33 or 44 (don't know about the 34),
but if you think one is necessary, I would use 0.1microfarad (100nF). 250v
is too low however to go across 220-240v mains. I would select a 450v part.
If you are in a 110 volt country, then 250v is OK, but I would still prefer
a 450v part in case you should ever sell the 33 to a European, or it ever
gets over here.

In order to comply with electrical safety codes, it'd be better to use
a cap which is specifically designed/rated for use in an "across the
mains" application. These typically have an X or Y type coding, a
high voltage rating (e.g. the ones rated for use in 280 VAC line
applications are actually tested out to 2000 VDC or above), and have
the capacitor encapsulated in a self-extinguishing resin to provide
some degree of fire resistance.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

[Mike Coatham]

Serge Auckland wrote:

wrote in message
...
Hi,

Would anyone know the apropriate value to used on the main switch
(volume & main switch) of the quad 33 preamp. I am replacing the on-
off & volume switch on such a unit . The part I am replacing has no
suppressor cap on it. I have a few 250 V small square film capacitors
(4700pF...up to 1 uF Siemen and RIFA @ 250V) on hand.

Thank you in advance

QUAD didn't fit suppressor caps on the 33 or 44 (don't know about the
34), but if you think one is necessary, I would use 0.1microfarad
(100nF). 250v is too low however to go across 220-240v mains. I would
select a 450v part. If you are in a 110 volt country, then 250v is OK,
but I would still prefer a 450v part in case you should ever sell the 33
to a European, or it ever gets over here.

S.

Err... you got that wrong. Quad did fit suppressor caps on both the 33 and
the 44. In the 33 it is bolted to the chassis adjacent to the volume
control- they call it a Mains filter SKF24R Dubilier. Value is .01uf + 220R
Similarly in the 44, from S/N 7001 onwards, a suppressor is fitted across
the power switch (inside the red box containing the switch & transformer)-
part number PMR209M-547-100 D N. The value is .047uf+ 100R.
And for completeness the 34 also has a supressor across the mains.
Source of information - Quad's own service manuals.

[Serge Auckland[_2_]]

"Mike Coatham" wrote in message
...
Serge Auckland wrote:

wrote in message
...
Hi,

Would anyone know the apropriate value to used on the main switch
(volume & main switch) of the quad 33 preamp. I am replacing the on-
off & volume switch on such a unit . The part I am replacing has no
suppressor cap on it. I have a few 250 V small square film capacitors
(4700pF...up to 1 uF Siemen and RIFA @ 250V) on hand.

Thank you in advance

QUAD didn't fit suppressor caps on the 33 or 44 (don't know about the
34), but if you think one is necessary, I would use 0.1microfarad
(100nF). 250v is too low however to go across 220-240v mains. I would
select a 450v part. If you are in a 110 volt country, then 250v is OK,
but I would still prefer a 450v part in case you should ever sell the 33
to a European, or it ever gets over here.

S.

Err... you got that wrong. Quad did fit suppressor caps on both the 33 and
the 44. In the 33 it is bolted to the chassis adjacent to the volume
control- they call it a Mains filter SKF24R Dubilier. Value is .01uf +
220R
Similarly in the 44, from S/N 7001 onwards, a suppressor is fitted across
the power switch (inside the red box containing the switch & transformer)-
part number PMR209M-547-100 D N. The value is .047uf+ 100R.
And for completeness the 34 also has a supressor across the mains.
Source of information - Quad's own service manuals.

Thanks for the correction. I have a set of QUAD circuit diagrams, and
there's no mains filter shown on those, so that's where I got my information
from. I have a 44 here, but haven't looked inside the red box for many
years, so don't remember ever having seen a filter.

Best regards

Serge
--
http://audiopages.googlepages.com