Here's
how to turn it on from the menu
Enable
the internal 50 MHz
amplitude reference signal as follows: (ESA E4401B and E4411B)Press Input/Output, Amptd Ref (On).
On 3/30/2019 2:26 PM, Michael Williams
wrote:
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Yeah,?
This has me scratching my head.
?Power supplies on a8 look good.
Get
Hmmm.. Ok.? -20dbm and 21.7Mhz.? Interesting case of
trouble.? Controller / PLL power supplies in check?? Loops
locked I guess, thinking what else to check.??
On Saturday, March 30, 2019, 1:13:21 PM CDT, Michael
Williams
<mike@...> wrote:
Hi Jon,
?
Yes, I see an IF
signal coming out of A8J3 when I follow the RF
verification procedure when using an *external*
50 MHZ source.? The signal does very with
attenuation, as describe in the service guide.?
?
-- Mike
?
?
Can you see a
21.7Mhz IF signal on the cable plugged into
A3J2?? I was looking over pages 55 - 75 of
the ESA Service guide for a E4401B and there
is a verification process to check on RF
deck function.? I only suggest this because
your original message stated your seeing
signals but wasn't sure if they were as
expected in Amplitude and correct
frequency.??
On Saturday,
March 30, 2019, 12:58:42 PM CDT, Tom B
<tbryan@...> wrote:
Did you
make sure the cal signal was turned
on?? You can turn it off on the
E4401B.
On
3/30/2019 1:39 PM, Michael Williams
wrote:
Hi Mark,
?
Thanks for
the reply and the thoughts.
?
From the
info in my CLIP, the 50 MHZ CAL
signal is generated by dividing the
800 MHZ 2nd LO by 16.?
The 2nd LO gets its power
from the TEST MUX (U56).? This mux
is dead ¨C no enable signal, no
activity on any of the control
lines.? That¡¯s where I¡¯m stuck, I
can¡¯t figure out if it¡¯s a hardware
or software issue that is causing
the 2nd LO to not get
turned on.? The CLIP is not very
clear on what tells the fractional
divider (U55) to enable it.
?
The 10MHz
reference clock is the timing source
for the 800 MHZ 2nd LO,
and is present, both internally and
at the 10MHZ output connector in the
back.
?
Thanks
again,
?
Mike
?
?
?
