Downstairs (IF2) HP3488 bits for digital output

04dec05

    The hp3488 is a digital output box that connects to the computer via gpib. There are two boxes: one that connects to the polA iflo and a second that connects to the polB iflo. Each box has 5 digital output cards and each card holds 16 bits (80 bits in total). Normally cards are configured for output only.  The table below shows the bits currently in use.
key:
IF2 HP3488 TABLE (last updated 01dec05)
name card 1stbit lastbit pols schem coding description
pre amp
1
0
2
ab
3
111  no gain
110  10db gain
100   20db gain
000    30db gain
3 10b amps at top of if2. When the bit is 0 the amp is inserted.
pre attn
1
3
6
ab
3
b0  1db  0 in,1 out
b1  2db  0 in, 1 out
b3  4db 0 in , 1 out
b4  4db 0 in , 1 out
11 db attenuators at input to if2. there are 4 attenuators 1,2,4, and 4 db each that are switched in / out by a single bit (0 --> in).
if Input
(sw141)
1
7
11
ab
4
11110 :1500
11101 : 750
11011 : 300
10111 : 750narBand
01111 : alfa
selects the input path thru the iflo
mix1inp
2
0
1
ab
5,6
00 : 1250
01 :  1500
10 : 1750
11 :  750
Selects the source input to the mixer
mix2inp
2
2
3
ab
5,6
see mix1inp Selects the source input to the mixer
mix3inp
2
4
5
ab
5,6
see mix1inp Selects the source input to the mixer
mix4inp
2
6
7
ab
5,6
see mix1inp Selects the source  input to the mixer
mix5inp
2
8
9
ab
5,6
see mix1inp Selects the source  input to the mixer
mix6inp
2
10
11
ab
5,6
see mix1inp Selects the source  input to the mixer
mix7inp
2
12
13
ab
5,6
see mix1inp Selects the source  input to the mixer
mix8inp
2
14
15
ab
5,6
see mix1inp Selects the source  input to the mixer
syn1 dest
5
0
1
a
8
00 : front panel
01 : 260->30 mixer
10 : vlba
11 : if2 mixers
set the output destination for the synthesizers. 
syn2 dest
5
2
3
a
8
same as syn1 dest
syn3 dest
5
4
5
a
8
same as syn1 dest
syn4 dest
5
6
7
a
8
same as syn1 dest
syn5 dest
5
8
9
a
8
same as syn1 dest
syn6 dest
5
10
11
a
8
same as syn1 dest
syn7 dest
5
12
13
a
8
same as syn1 dest
syn8 dest
5
14
15
a
8
same as syn1 dest
transfer
switch
5
0
0
b
2
0 switched
1 unswitched
switches polA,polB IF at input to iflo. Unswitched is the normal straight through mode.
260to30
2or4pols
5
1
1
b
10
0 4a  0b
1 2a  2b
the 260 to 30 mhz down converter can output 2 channels pola, 2 channels polB or 4 channels polA (this is mainly used for the crr aeronomy experiments)
430blanking
5
2
2
b
10
0 no blanking
1 blanking
lets you blank the IF input  to the 260 to 30 Mhz converter while the 430 transmitter pulse is on.
alfaamp 5 3 3 b 0 out(nofilter)
1 in (with filter)
switch alfa IF1 amplifiers for 1440 100 Mhz filter in or out.
cal source
5
4
6
b
12
0 : interim corr.
1 : 25 hz cal
2 : wapp
3 : unused
4 : cal on
5 : cal off
6 : front panel bnc
7 : front panel switch
Determines which ttl signal goes up to fire the cal. The 3 bits are decoded to a number 0 through 7. These values are 1 less than the numbers you input with the routine calport.
visitors 30Mhz
5
7
7
b
11
0 : from ch
1 : from dome
determines which 30 Mhz IF goes to the visitors equipment 30 Mhz (in the computer room).
signalSource
5
8
9
b
1
0 :  ch
1 : dome
2 : noise source.
Chooses the input IF. ch is from the 30 to 260 Mhz upconverted. Dome is the fiber from the dome. Noise source is the one in the if2 racks.
blankers 5 10 11 b 11 : faa
10 : iridium (N)
01 : iridium (M)
00: extra
control which blanking signal goes to the backends. N is normal iridium blanking (50 %duty cycle) M has a larger blanking duty cycle.

 
 
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