[time-nuts] E1938A oscillator pinning
kscally at bytecan.com.au
Mon Aug 27 20:53:24 EDT 2007
The DB25 pinning is as per TVB's web site:
The EFC voltage info is as follows (courtesy of Rick K):
The 10811 was bipolar +/-5V as you said. The cathode of
tuning diode was connected to a 6.2V zener diode that
sort of ovenized. The concept was that if you did NOT
to use the EFC, you simply grounded the EFC pin.
The E1938A has unipolar 0V to 5V EFC with the anode of
the tuning diode grounded. A 2.5V reference IC that
is ovenized provides a stable 2.5V to bias the diode if
do NOT want to use the EFC.
I concur with Bruce's on-board LED description.
My experience is that the "hockey-puck" oven takes close
on 15 minutes to "stabilise" (settle) - in the Z3815 at
(user of many Z3815A GPSDO's)
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