5. Parameters of "Device Table"

File Name : File name of "Device Table" to save.

Frontend

Synthesizer : Number of synthesizer.  This is set automatically by selecting a receiver.
 

RX	Synth
H22	2
H28/30	2
H40	4
S40	2
S40M	3
S80	2
S100	1
S115Q	1
Rainbow	3

Receiver : Select a receiver from the list shown by pushing the right buttons. Available combination for simultaneous observations are S40+S100 and S80+S100.

Track Frequency : Tracking frequency. (150 GHz for NOBA)

Sideband : For SSB (Single Side Band), SSB Window appears to set parameters as shown in fig 5.2.2. Some receivers can be used with SSB only. For NOBA, you don't have to select sideband.
 

RX	Sideband
H22	USB
H28/30	USB
H40	LSB
S40	DSB or LSB(35-47 GHz), USB(47-50 GHz)
S80	DSB or LSB(72-113 GHz), USB(113-115 GHz)
S100	DSB or LSB(77-113 GHz), USB(113-115 GHz)
NOBA	-

Backend

Type : Type of backend. Default is cont3.

Channel Begin-End : Begin and end channel numbers which you use.

• NOBA : 1-7
• Others : The avilable channels are from 9 to 14. For simultaneous observations, select a series of channel (e.g., 10-11).

Reference Channel : Channel number of the reference signal for lock-in procedure.

• NOBA : 1
• Others : 8

Monitor Channel : Channel number of sky monitor.

• NOBA : Blank
• Others : The available channels are from 15 to 17. Default is 15.

Channel Notes : You can write a comment for each channel.  For use, Channel Notes Window appears.

Option : You can change parameters of the backend (In general, you don't have to change them).  For use, Option Window appears to set parameters.

RX Rotator : Position angle of rotators for multi-beam receivers to compensate image rotation.  When you use a multi-beam receiver (NOBA, BEARS, S115Q), select use. RX Rotator Window appears.

Switching Mode :

Beam switch : Default. Beam Switch Window appears to set parameters. In general, you don't have to change them.
bias : NOBA
non : DC measurement.

• SSB (Single SideBand) Filter

Fig 5.2.2  SSB Window





IF : Track frequency is converted to IF by 1LO. IF is converted to IF' as listed below.
 

RX	IF'
H22	IF
H28/30	IF
H40	IF
S40	IF + 4.0 GHz
S80	IF + 4.0 GHz
S100	IF + 4.0 GHz

Set IF so as to be in the range of 5-7GHz after this conversion. The commonly used values are listed below.
 

RX	IF (GHz)
H22	6
H28/30	6
H40	6
S40	1.375
S80	1.375
S100	1.375

Sideband : Select LSB(Lower SideBand) or USB (Upper SideBand).

• Channel Notes

Fig 5.2.3  Channel Notes Window


Chan (1) - (60) : Enter comment for each channel.

• Backend Option

Fig 5.2.4  Option Window


Sampling Interval : Interval of data sampling by A/D convertor.  Default is 1 msec.

Integration Time : Integration time. Default is 100 msec.

Trigger Mode : Select INT (Internal) or EXT (External).  Default is EXT.

Filter Mode : Select HPF (High Pass Filter) or BPF (Band Pass Filter).  Default is HPF.

HPF Frequency : Cutoff freuency of high pass filter.  Default is 10 Hz. For BPF, this is the center frequency of band pass filter.

BPF Q : Q value (Q = f/△f) of band pass filter.  Default is 3.

LPF Frequency : Cutoff frequency of low pass filter. Default is 4.
 

• RX Rotator

Fig 5.2.5  RX Rotator Window


Initial Angle : Position angle of the rotator of a multi-beam receiver on the specified coordinate system in "Scan Table".

• Beam Switch

Fig 5.2.6  Beam Switch Window


Rotation : Default is free.

free : Enter rotation rate per minute (rpm). Default is 465 rpm.
phase locked : The phase of the rotation of the chopper can be locked by using a function generator.

Reference Position : Position of the mirror. The beam throw depends on this parameter. Default is 500 mm. There are two modes of beam throw, 0 and 8 deg. Default is 0 deg.

Load Position : Load position during observation.

SKY : Default.
LD1 :