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Misc
====
01-Aug-1996 Hobart no longer requires sampler mode=1 (sign <-> mag swapped)
20-Aug-1996 Discovered Mopra was linear polarization at S-band, since at least
June 1996.
20-Aug-1996 The X-filt at Tid is not INVERTING at 16MHz, when requested.
This problem affects V076 (Mar 96), V089A (Aug 96) + others
(Problem was that manual inversion command had no effect
on odd-numbered filters or filter 0).
1996 CAOBS/CACOR quits 1 cycle before end of scan in UTC mode

---Individual expts-------------------------------------------------------
vt001 1996/044 Mopra-Hobart
Mopra VAX clock 1s fast (adjust PB time diff to be 10n+1 sec)
Short break in Hobart tapes ~073350.
At 044/0736, Mopra stats= 50.0, 34.3, 49.9, 34.4
Hobart stats= 48.2, 52.5, 48.5, 56.1
NB Hobart ch 2 (mag bit, 2nd IF) is hunting on 10s intervals,
typical sequence 43.1,43.1,37.2,43.1,43.1,43.1 (0738 UT)
46.4,40.7,43.1,50.6,29.9 ... (at 1341UT)
31.2,59.1,31.2,59.1,31.2 ... (13:41:40~13:49:00)
It seems correlated amp is indeed ~ sqrt[16*n+(1-n)], where n=
(in above period, amp~25.5Jy for 31.3%, ~33Jy for 59.2% in F2, and
~30.5Jy for 48.1% in F1).
another long sequence: 62.3,37.8,56.1,24.3,62.3,... (~1403UT).
associated fluxes: 33.5 28.0 32.3 23.5(33.5) (Hob is rotated ant?)
1440~1448, 59.6%(32.6Jy), 30.8%(25.3Jy)

At 044/1331, Hobart stats=48.3, 57.1, 24.5**,52.2
Mopra stats=49.9, 34.5, 50.0, 34.5%

March 1996 session;
Parkes: JER + PAJ
Mopra: AKT
ATCA: RGG + Gregory Tsarevsky
HOBT: MEC + ?

V076B
at 083/2207, Hobart stats=47.8%, 54.4%, 47.9%, 54.6%
at 083/2207, Parkes stats=50.0%, 33.9%, 50.5%, 34.8%

Fringes Parkes-Hobt on 1921-293, 083/2211-2300 (Hobt F1/F2 reversed)

PSR_REFS2 085/0700-1500 CAT16, MOPRA, HOBART
PSR_REFS3 085/1700-2100

085/0713 stats: CAT16 49.9,34.3,50.8,33.3
MOPRA 50.0,34.5,49.9,34.5

No fringes found to Hobart at all. Huge cal tone in middle of band
probably clobbered them.

Mopra VAX was 1s fast wrt UTC (gating pulse 1s early on tape).

V083B 1996/119 Parkes-ATCA-Mopra, 1419MHz/8MHz "nuggets" expt
JER (Narrabri), AKT (Mopra), EAK+DLJ (Parkes)
Mopra Vax clock out by 1 second

V076D 1996/168
DSS43: had wrong statistics on F1 until ? (Xfilt in wrong lock).
at 0105UT DSS43=50.0,63.8,50.0,34.6, HOBT=34.6,50.0,34.6,50.0%
Tid S2 was 18 sec slow until 168/0426.
The two freqs at Tid have opposite sidebands (Xfilt s/ware prob).
Pks-Hobt changed F2 at 0915UT (22210->22185).
All stats had F1/F2 in right order. Polrn looks OK.
Hobart has v. high Tsys still: same as March?
Either Tid or Pks has coherence problem. Should check against Hobt.
*Problem is Tid! See plots in VLBI_1/vlbi/lba_plots.

Using FRING SNRs on 1144-379, =16.9: thus
estimate SEFD(H)= SEFD(P) * 16.9**2 = 285kJy (assuming 1144-379
unresolved: agrees well ratio from Circinus, below).

V076E 1996/171
DSS43: cal tones left running until ~0640.

Using FRPLT (chann 251, 2~4m intgn) get ~21Jy on TP and ~2.9Jy on TH
=> SEFD(H) = 5000*7.4**2 = 275kJy.
Autocorrelations: DSS43 ~21Jy (100mG) at Ch 501/1025 in F1
PKS ~20Jy (20mG)
HOB ~5Jy? (~1mG: very approximate) 0640-0700
HOB <2Jy? 0440-0600 (but corr. problem)

DSS43 ~9Jy (46mG) at Ch 376/1025 in F2
PKS ~10Jy (7mG)
HOB <1Jy (.2mG)

VT003 - MK3 VSOP test at 22GHz.
HOBT missed WHOLE RUN (encoder problems; Rx was NBG anyway).

V074A
PRKS-CAT24-MOPR-HOBT
HOBT off air for WHOLE RUN (18 hours) with encoder problems.

cross polar purity on 1934-638 (1347UT):
RL/RR ratios: PKS-CAT=1.25/15, PKS-MOP=1.1/15, CAT-MOP=~2.3/17

V074B 172/0000-173/
Polarizations agree! All bands inverted except PKS.

Stats: 49.9,35.9,50.0,32.4 172/0355 PKS
50.0,34.6,50.0,34.5 172/0356 MOP
49.6,32.9,50.7,32.8 172/0356 CAS
34.4,50.0,34.6,49.9 172/0357 HOB

49.9,33.8,50.0,34.0 172/2005 PKS
50.0,34.9,49.9,34.6 172/2008 MOP mag bits 33.7~35.0%.
49.6,33.2,50.7,33.3 172/2015 CAT mag bits 30.5~33%
34.4,50.0,34.9,49.9 172/2016 HOB
V074C
Hobart: observed 1934-638 instead of 1921-293 at end (didn't change
schedule from original).
also missed 0537-441, apparently. Problem with online system
(see log).
High errors on atnf0206-1 around and after ~174/1840 on s2at12/3.

Parkes: grotty bandpasses, especially Ch2=LCP
Ch2=LCP has 1mHz comb offset by 0.5MHz, at 174/0420

CAT : significant DC offsets on both channels

Tid : large midband birdie: 250Jy(35Jy) in 2048 channels appears
suddenly at 173/221320. Just before that, seen at 1610.4.
Looks like test tone left on!

Can see GLONASS in lag spectrum at 173/214730 onwards! Seen at lag
~-590 on MOP-CAT
Huge GLONASS seen at 174/0747 on Mop-CAT at lag ~50.
also at 174/1745 " " ~600.
Stats: PKS 1747 : 49.98,34.67,50.03,34.66
Mop 1750 : 50.02,33-35,49.98,34-35 GLONASS?
CAT 1754 : 49.75,31.3,50.70,31.7
Hob 1757 : 34.88,50.05,34.72,49.97

Mop 1800 : 50.04,35-37,50.02,34.8
CAT 1803 : 49.60,32-34,50.66,29.5
PKS 1915 : 49.95,34-35,50.03,33.5-35
Mop 1916 : 50.03,34.7,50.00,34.5
CAT 1919 : 49.70,33.18,50.65,33.35
Hob 1921 : 34.72,50.05,34.65,49.96

PKS 2220 : 49.95,33.6-35.0,50.02,34.1-36.0
Mop 2224 : 50.01,33.2-34.5,49.99,33.8-34.2
CAT 2226 : 49.54,32.2-36.5,50.77,31.9-34.7
Hob 2229 : 34.65,50.05,34.4-35.0,49.97
Tid 2230 : 49.98,34.77

PKS 0412 : 49.95,34.7,50.02,34.3-.7
MOP 0414 50.02,33.8-35.2,50.01,34.6
CAT 0416 : 49.66,32.7-33.1,50.77,32.5-32.8
HOB 0418 : 34.5,50.04,34.6,49.98
TID 0419 : 50.05,34.77

V075
ATCA = LCP,RCP until 176/0130, thence RCP only
Mopra= dual linear (recorded ChA?)
checking at ~176/0120 on 0537-441 (on 3-Sep-1996)
Stats: ATCA=49.0%, 33.1%, 50.6%, 31.6% (176/0120)
Hobt=34.6%, 50.0% (176/0119)
Polarization ratios: LR/RR < 0.2/4 (20:1) for PC, HC
TC=0.25/4.7 HC=0.10/3.6 (176/0125)
Sideband reversal: PC = .05/4 (flip Pks): HC,HP ~ .2/4 (flip Hob)

: TC = .2/4.7 (flip Tid), HC=.1/3.6 (flip Hob)
Tsys at 176/0120, assuming 0537-5Jy: CAT=160, T=14, H=770 Jy.

Stats at 175/1813: P=49.5%,34.6%: T=50.0,34.6, H=42.5,42.1% !!

V041L : A troubled run indeed.
Cal tones: fractional power in 1024ch: (S and X respectively)
Tid ~1 (20/20), ~1 (30/30)
Hob ~5! (150/30), .3 (13/30)
Both bands at both stations are apparently INverted
Hobart had pointing problems early (missed 0537-441), and
LO failed sometime before end (LO unlock indicator found on ~0500UT).

Tid had problems with S2 early (first ~20m?): loss of sync to S2 (bad trk
on Martins Veroboard).
Tid level on channel 2 was "sawtoothing" owing to DC offset into sampler:
the stats are ~48.5%.

HUGE 50HZ Modulation problems!
197/0116 : fringe rate goes through 50Hz: HUGE spike caused by cal tones
cross-correlating (~1Jy in central 16ch, ~50Jy in 512ch config)
Setting fringe-rate to zero (with S2FO) increases ampl. by only ~2x.
Tried correlation with 50Hz offset: Vela (S-band) amp down by only ~2x!

Fringes disappear altogether between 0140-0200UT

The Mark3 was a complete disaster at Hobart.

COR9606 1996/181/2245-0626 Tid(DLJ) Bear Lakes(Igor et al.)

Recorded at Tid in 4p8-2 with Xfilt, reocrding 4 2MHzx2bit bands;
1660.99-1662.99
1662.99-1664.99
1664.99-1666.99
1666.99-1668.99
DLJ was disinclined to disrupt operations by changing configuration
for the OH source (0644+002): Igor wanted a single 4MHz band centred
on 1666.99 for this source. Ultimately Tid just kept same config, thus
the data can't easily be correlated.

Bear Lake only recorded only the two higher bands, in mode 4x4-1,
except for two scans on the aforementioned source (0644+002) which
were recorded in 8x2-1 mode, 1st channel 1664.99-1668.99, 2nd channel
blank.


TH96193
0537-441 AT 1/0432-0450UT
Hobt stats (34.7%,50.0%)x2 : all OK
Tid stats: ~49%, 34.7%, 50.0%, 34.7%
Hobart 8MHz bandpass characteristically asymmetric
Tid "8MHz" bandpass also characteristically asymmetric
Amplitudes on 0537-441 much lower than expected (0.9Jy S, 1.5Jy X)
Tid evidently recording inverted, BUT flipping to UNinverted results in;
-amplitude drops only 1.5JY => 1.05Jy (X-band) and 0.9 => 0.5 Jy (S-band)
-delay on X-band changes by 1 bit (~62nS), S-band not clear
-fringe-rates stay the same
-correlated bandpass at X-band has sawtooth shape, rising linearly with
frequency, and with non-linear phase. (Bandpass with INverted Tid looks
like product of the two AC bandpasses).
Weak birdy in Tid S-band AC is symmetric about band centre!
Correlating at 2282/2298/8417/8433 MHz gives low amp, high rates

Tests by Martin O suggest that the problem could have been an interruption
to the 32MHz Xfilt clock, causing weird behaviour. (Requires operator to
enter and exit one of the screen menus, causing fresh parameters to be
downloaded to the Xfilt).

th96206
looked OK
Tid had both S and X sidebands reversed.

th96209
looked OK
All sidebands normal (USB)

th96211
Tid gap in recording: 211/23:10:10-23:13:58,
just later, at 211/23:15:53, alignment lost again, briefly.
(Almost as though 'time s-1' command had been entered).

th96219
No fringes detected at X-band though perfectly normal fringes at S-band.
Stats looked normal, bandpasses at Tid reversed wrt th96209
There is an odd ~1.5% correlation between the two Hobart passbands
(indicating leakage somewhere).

Aug 1996 Session, 11-19 August 1996
Personnel: Parkes=JER, Ken Simpson, DLJ (10-15/8)
Mopra=EAK, AKT (10-13/8), David Rayner (13~19/8)
Narrabri=RGG, Andrew Smith
Tid=DLJ
Hobart=MEC,SE,David Legge (V088)
Notes: Mopra Vax clock was +2s fast on day 231

V057C-1 Hobart=MEC
Hobart observed entire expt at wrong frequency
Parkes=JER/DLJ/Ken Simpson
Parkes started late (~0851?) with Rx probs
Parkes had 4MHz intermittent/crappy filter until ~1030?

V057C-2 Hobart=SE
-Hobart sideband NON-inverted (all others inverted)
Hobart statistics good at 15:59UT (50.0,34.6,49.9,34.9)
-At ~1550 (1921-293):
Tsys correction factors PKS-CAT-HOB (assuming 1921-293=20Jy):
LCP RCP
PKS 1.200 1.005
MOP .833 .745
HOB 1.200 .806
Cross-hand amplitudes: PKS-CAT ~3,1Jy; all others ~1.5Jy,

V088A-2
All polarizations aligned, apparently.
Mopra= EAK/AKT
Absolutely horrible bandpasses at L-band
Hobart=SE
Started late (OK by 0042: SE, stats OK 004120)
Estimated Tsys=2200Jy (SE)
Hobart has sideband reversed wrt everyone else (contrary to spec)
21,000/1400 Jy tone at ~1375.5MHz (1024ch) (RCP)
8,000/1400 Jy " " (1024ch) (LCP)
Polarization purity poor(?):
On 1921-293 226/1615, RR=LL/RL=LR ~ 2.25 (HOB-CAT)
~ 2.9 (HOB-PKS)
Parkes
Pol purity: PKS-CAT : LR,RL = 1.0, 0.3 Jy (RR=LL ~ 10)
PKS-MOP : LR,RL = ~0.5Jy (RR=LL ~ 8)
CAT-MOP : LR,RL = ~0.3Jy (RR=LL ~ 8)
poor tape readback on ATNF0353.1 after 226/0525. Recorr'd with 1-2 swpd.

V088A-3
Parkes now using "good" 16MHz filters (from George Graves) but has managed
to reverse polarizations!
Mopra gain apparently lousy: ~800Jy?
Nothing usable before ~1640 UT (Parkes-CA)
Parkes messing around 1645~1647 (test tone)
At 227/2140 (0826-373):
Pol purity: LR/RR = ~0.2, 0.1, 0.15 / 2.2Jy for PC,PM,CM resp.
Mopra Tsys seems to be ~800Jy, and ATCA ~ 400Jy.

V088A-4,5
Mostly as for V088A-3
Narrabri is quitting scan early (~10s before STOP time), and writing rubbish
for first ~30s of each scan.

V079
1921-293 at 0/1500-1520
PKS,CAT,MOP stats OK
Polarizations all aligned (PKS,CAT,MOP,HOB)
Hobart has sideband reversed wrt everyone else
Hobart has poor phase-noise, dropouts, coherency problem?
Cross-hand polars: PC,PH ~1/15; others ~0.5Jy/15Jy
PKS has weak birdie at 6669.0MHz (~2xTsys in 1024 ch)
MOP Vax clock 1s fast: align tapes to -00:00:01 for A/C s.
Cross polars in detail, 1515-1520UT;
PC PM PH CM CH MH
aa 15.3 13.6 12.5 13.2 12.7 10.5
bb 14.7 13.1 12.0 13.3 ~13 ~10.8
ab 1.05 0.55 0.3 1.2 1.1 0.5
ba 1.2 0.55 0.8 0.75 1.2 0.4
Relative gain corrections (assuming 1921 = 14.9Jy);
PKS=1.00=>100, CA=1/1.04=>208, Mop=1/.77=>1040, Hob=1/.684=>1462

G351.78 line heights at 1030UT:
PKS=405/155,375/150 => 2.56 AT=395/210 => 1.88
Mop=973/835,965/835 => 1.1605 Hob=1480/1165, 1290/1030 => 1.261
Relative SEFDs: 1.00 : 1.77 : 9.72 : 5.98(!?)
It appears as though Hobart may have a large amount of short-term phase
noise, since there is a large discrepancy in Tsys from A/C and from
1921-293 (although the latter may be resolved partially).

G351.78 line heights at 1430UT:
PKS=400/160,370/140 AT=380/210
MOP=955/835,955/840 HOB=1470/1170,1280/1020

STATS:

0236 PKS=50.0,34.7,50.0,34.8 CA=50.2,34.7,51.1,34.5 (PKS=0240)
MOP=50.0,34.5,50.0,34.4 HO=50.1,34.8,49.9,34.7

1050 PKS=50.0,34.6,50.0,34.7 CA=50.3,33.0,51.1,32.9
MOP=50.0,34.6,50.0,34.6 HO=50.0,34.6,49.9,34.7

V089A
Tid spectrum is INVERTED on both bands, all 3 days (X-filt bug)

TH96246 - "VLBA Mode" test
Test of "VLBA" mode at Tid and Hobart. Xfilt was brought to Epping on the
previous Friday to be modified (by Martin) so that LBA mode could be
selected by DIP switch on rear. Also new version of software to fix
"bit flipper" purportedly supplied, but still didn't work?

Tid 2nd channel has stats of ~67.05% after decoding (mode=2), while
1st channel is OK with stats of ~34.5%. A/C spectrum of Ch2 also looks
odd, with no taper on one end. Reversing sense of second sign bit
(with custom adaptor cable) fixed stats (=> 33.5%) but spectrum looks
much worse. Speculation that 2nd channel was on "false" lock, as seen
by EAK in June 22GHz run.

Hobart looks OK except for usual asymmetric 8MHz bandpass.
Large differential delay between S and X (~80nS!).

001230: Glitch in Tid X-band: MSB jumps up to 68%, LSB to 33% for ~2s.
Delay jumps by 16nS! Stays there until 001420, when there's
another glitch/dropout (LSB stats again glitch to 33% momentarily)
whereupon delay jumps back by 16nS. S-band totally unaffected!

vt004 1996/290 Hob,ATCA
Hobart withdrew on the morning: had replaced Az encoder cards the day
before and couldn't drive antenna.

ATCA correlator cycle (10s) was 5sec out of sync.
Stats: at 1158UT: 50.0,32.7,50.8,34.2 (default CATIE => R,L)
1201UT: 50.8,34.1,50.0,32.7 (swapped CATIE to get L,R)
1253UT: 50.7,33.4,50.0,33.4

th96306 - S/X between Tid and Hobart.
Hobart adjusted 8MHz filter arrangement: now see well tapered (over
tapered) edge on passband.
S-band amplitude on 0537 (~4.0Jy) both at start and end but
X-band amplitude way down at start (~0.75Jy), OK at end (~4.2Jy).
Short break in Tid tape, ~306/13:40:55

Tid stats
1344UT 49.96,34.76,50.02,34.76
1746UT 49.97,34.77,50.02,34.77
Hob stats
1328UT 50.03,34.70,50.00,34.65
1732UT 50.04,34.64,50.00,34.78

Tid tcp's: 2047,2210,2142,2171,2183,2222,2146,2221
Hob tcp's: 2148,2145,2166,2165,2144,2123,2177,2178

vt007 - VSOP/18cm, Hobart, DSS43, Usuda, Shanghai
Shanghai probably didn't record any good data: S2 configuration probs?
DSS43 recorded 20MHz off in both channels, owing to JER error.
Hobart: can see all expected OH lines on VYCMa and Orion.
Shan: stats at 1416: 49.1%, 53.4% (29.8%)
Hobt: stats at 1420: 49.9, 50.0 (34.7), 49.9, 50.0 (34.7)

Shan: tape problem- trouble reading aux data on all tapes, even though
error rate is OK (<1E-5). Same thing seen in TS97340.

TS97340 - Test DSS43-Shanghai, 2290/8425MHz
Shanghai recorded 1bit data only (32x2-1), and only from 1140-1530 UT.
Tapes copied to 32x4-2 (ATNF0245).

Tid turned on S-band test tone (2290.0) at 151430~152400 ?
(Clobbers S-band completely)