The most useful log is the scanned hand-written log.
Notes on interpreting the contents are given below.

The Pet-2000 computer log was introduced in 1999.
It does not show heater modulations well but gives
more detailed transmitter parameters such as power
and phase sampled at specific times about 1 min apart.

Notes on interpreting the heater handwrittem log.
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Power
-----
The power is given as power per transmitter.
To calculate the effective radiated power, ask mike@eiscat.uit.no
or look at http://www.eiscat.uit.no/heating/ht_arr_gain.png.
Basically it is no_of_transmitters * Power * antenna_gain, 
but antenna_gain changes with frequency, no_of_transmitters and pointing.

Transmitters
------------
The number of transmitters has a maximum of 12.
The notation 1-12/5,6 means transmitters 1 to 12
except numbers 5 and 6.

Mode
----
The mode symbols O means Ordinary-mode circular polarization
and X= Extra-ordinary mode circular polarization.

Direction
---------
The direction is given as degrees off zenith in the north-south
plane. Negative angles are southward.

Modulation
----------
The term "CW tune" is really a misnomer. It should be called 
something like "powering up and phasing" and is used to denote 
the roughly 2-min long
procedure whereby the transmitter phases are changed from random
values to those defined for the desired polarization and beam direction,
as the power is slowly increased to the desired maximum.
The transmitters are actually self-tuning.
The exact sequence of events is not well defined and sometimes
problems occur with one or more transmitters causing the process to
stop before the final parameters are reached.

CW=continuous wave (no modulation)
AM=amplitude modulation

Dowden beam sweep unit is a hardware device which converts
an input voltage into a phase difference between rows of transmitters
so as to allow beam steering at rates from dc up to 5 kHz in the 
north-south plane. It was built by Richard Dowden (RLD) in 1980
and so is often referred to as the RLD unit.

Timing is usually determined by a GPS-controlled clock.
But depending on the hardware used, the timing of modulations
may have delays up to a few hundred microseconds.
Modulation using the Texas-Instruments computer may have a 660 microsecond
delay.