Technical
issues
with
Jenny
Reloaded
VFD
clock
Please
read
carefully
!
On
some
Jenny
models
an
issue
occured
either
at
once
or
after
some
time
of
operation
that
the
MosFet
T2
runs
hot
and
the
clock
was
not
functional
anymore.
At
the
same
time
C13
and
/
or
C20
became
discolored
and
also
runs
very
hot
because
of
an
internal
short
circuit.
It
was
detected
that
this
ceramic
capacitors
were
taken
from
a
batch,
which
is
unable
to
withstand
the
47
V
operating
voltage
(the
spezification
of
the
capacitors
is
50
V)
for
a
longer
time.
Please
check
first,
which
type
of
capacitors
the
clock
is
equipped
as
follows:
Disconnect
the
clock
from
power
and
unscrew
out
the
PCB.
Locate
now
the
positions
of
C13
and
C20
with
the
help
of
both
left
illustrations
and
check
the
type
of
the
capacitors.
"Good"
capacitor
"Bad"
capacitor
No
modifications
Capacitors
C13
and
C20
need
to
be
made.
needs
to
be
un
‐
soldered.
The
clock
is
equipped
in
total
with
eight
of
this
100
nF
capacitors;
either
the
"left"
or
the
"right"
version.
The
possibility
of
a
failure
only
can
happens
on
C13
and
/
or
C20;
which
means
that
the
remaining
six
"bad"
capacitors
can
be
remain
soldered
in.
For
de
‐
soldering
capacitor
C13
/
C20
please
do
the
following
task:
Heat
up
both
solder
pads
of
each
capacitor
simultaneous
with
the
help
of
a
fat
drop
of
solder
tin
and
pull
out
the
capacitors
with
tweezers.
Next
clean
all
pads
with
a
de
‐
soldering
pump.
With
this
method
your
clock
is
temporarly
functional,
but
it
is
strongly
recommended
to
replace
C13
and
C20
with
100
nF
/
100
V
versions.
Furthermore
it
was
mentioned,
that
both
electrolyt
capacitors
C5
and
C6
are
driven
nearly
outside
their
voltage
range
(25V
each).
No
issues
were
reported
so
far,
anyway
it
is
recommeded
to
solder
both
electrolyt
capacitors
a
resistor
of
47
kohms
each
in
parallel
for
improved
voltage
‐
symmetry.
On
request
the
manufacturer
offers
a
free
upgrade
set,
composed
of
2
x
ceramic
capacitors
100
nF
/
100
V
and
2
x
47
kohms
small
sized
resistors.
Please
contact
the
manufacturer
via
at
These
modifications
only
affect
clocks
up
to
serial
‐
no.
JR
‐
267
Starting
from
serial
‐
no.
JR
‐
268
adequate
improvements
has
been
made.
