Lavry DA2002 Operation Manual - page 11
11
fingerprints.
The front panel is gold plated (24 karat gold). Use a soft cloth (and plain water, if necessary) to clean
a long-term reliability standpoint.
maximum). The temperature rise is no cause for concern, but allowing for some airflow is always a benefit from
linear power supplies and discrete class A analog circuitry generates a significant amount of heat (25 watts
The Model DA2002 is an auto-calibrating converter requiring no periodic adjustments. The unit's reliance on
Maintenance
operation requires 115 volts AC.
Operation up to 240 volts is possible with no change in performance using the 220 volt setting. Optimal
accommodated. Two fuses are required.
operation requires 1/4 ampere 250 volt fast blow fuse. Both American and European size fuses can be
switchable on the back panel. 115 volts operation requires a 1/2 ampere 250 volt fast blow fuse; 220 volt
The Model DA2002 operates at 50 or 60 Hz, and has two line voltage selections, 115 volts and 220 volts,
Power and Fusing
side) may prove useful.
electrically noisy environment, a termination impedance of 600 Ohms (at the destination, not at the DA2002
loads. As always, for best results it is recommended to use high quality cables. When running a cable through an
The transistor based output drivers are short circuit protected and are capable of driving balanced 300 Ohm
incorporates a seven pole analog filter.
oversampling operation pauses an increased requirement for analog anti imaging filtering. The DA2002
further reduce sensitivity to jitter. The upsampling filter is calculated by the DSP. The tradeoff in favor of low
The DA2002 operates in low oversampling to allow for maximum settling time of the DAC circuits and to
Output filter and drivers
of D/A update rate.
requires pre storage of about 5 words of data for 1 second D/A stepping, or an 50 word memory for 10 seconds
fact, the data storage is very small and so is the delay. An "unrealistic" 100ppm per second input rate step
At first glance one may get concerned about the potential long delay due to storage of a lot of data samples. In
or becomes empty.
track, the long-term average drift is done just fast enough to make sure that the buffer memory does not overfill
data in a dedicated memory to guarantee that each clock cycle can find its data. Moving the clock slowly to
between the input and the too steady of a clock circuit. The DA2002 CrystalLock (TM) approach, stores enough
PLL will cause loss of lock because the slight variations in incoming data rate cause loss of correspondence
more) in a manner allowing it to track only very long term average drift. Using such an approach with ordinary
filter circuit). The oscillator frequency is change by tiny amounts (.1ppm) and not very often (15 seconds or
variations. The clock oscillator is controlled by a processor driven DAC (not an ordinary phase detector plus
crystal oscillator but the control signal for the crystal is freed from having to track down incoming clock
The DA2002 uses a non-standard approach for removing jitter. The deglitcher circuit is clocked by a pullable
Operations Manual
DA2002