A journal of the observations is given in Tables 1 (click here) and 2 (click here). The quoted parameters of the programme stars are from DS93.

The observations were performed with the B&C + CCD spectrograph at the 1.50 m ESO telescope. We used a 400 l/mm grating and a 2 arcsec slit, resulting in a resolution of 7 Å and a wavelength range

3300-9100 Å. For V442 Cen and V650 Cen the observations were performed with a 600 ln/mm grating, giving a resolution of 4.7 Å and a range covered of

3470-7370 Å. The slit was always rotated perpendicularly to the horizon in order to minimize problems connected with differential atmospheric refraction. The seeing has always been significantly narrower than the slit width (in the FWHM sense). The details on observing strategy, data reduction, seeing and spectrophotometric standards are similar to those of the previous papers in this series.

The atmospheric extinction and instrumental response have been derived individually for each observing night from observations of spectrophotometric standard stars. Inter comparison of the latter throughout the whole observing run shows that the mean rms error of the absolute flux calibration does not exceed 4% over the

Å\ wavelength range. Outside these bounds the flux calibration errors may increase appreciably.

**Table 1:** Journal of observations of the programme stars. Type, Max and Min as listed by DS93. Code for spectral information available in literature (DS93): N = no spectral information; D = only a glass plate tracing or a description of the quiescence spectrum; X = only a glass plate tracing or a description of the outburst spectrum. Status of the object when we have observed it: Q = quiescence; *Out* = outburst
Name			Type	Max	Min	Code	Observ.	UT	Expt.	Status
				(mag)	(mag)		date	(mid-exp)	time
V650 Ori	05 31 08.25	+09 45 09.9	UG:	15.5 p	>17.5 p	N	07.02.96	01:23	60	Q
DE Cnc	08 35 27.33	+19 45 29.2	UG	14.6 p	18.0 p	N	08.02.96	03:40	60	Q
1H 1025+220	10 28 00.15	+21 48 12.9	nl	16.2 V		N	09.02.96	04:37	60	Q
V442 Cen	11 24 51.99	-35 54 38.6	ugSS	11.9 V	>16.5 v	D	07.02.96	06:46	45	Out
PG 1157+004	11 59 52.00	+00 07 51.4	cv:	15.9 B		N	09.02.96	05:48	45	Q
IM Com	12 31 16	+14 12 14	UG:	17.6 B	18.5 B	N	11.02.96	06:51	60	Q
AP Cru	12 31 20.34	-64 26 24.3	n:	10.7 p	21.7 j	N	10.02.96	03:44	90	Q
V485 Cen	12 57 23.38	-33 12 07.7	ug	12.9 p	17.9 V	D	09.02.96	06:54	60	Q
PG 1510+234	15 13 02.35	+23 15 07.0	cv	15.1 B		N	11.02.96	09:10	40	Out
EK TrA	15 14 01.20	-65 05 35.7	ugsu	10.4 v	16.6:v	X	28.05.96	04:05	60	Q
PG 1522+122	15 24 27.32	+12 02 06.3	cv	16.1 B		N	11.02.96	08:06	60	Q
BR Lup	15 35 53	-40 34 07	ugsu	13.1 p	17.5 p	X	29.05.96	01:47	60	Q
IM Nor	15 39 26.20	-52 19 21.3	n:	9.0 p	22.0 j	N	29.05.96	03:07	60	Q
HP Nor	16 20 49.64	-54 53 23.3	ugz	12.8 v	16.4 V	D	28.05.96	05:13	50	Out
IK Nor	16 25 28.97	-55 20 03.4	ug	12.9 p	16.3 p	D	29.05.96	04:21	60	Q
KQ Nor	16 27 30	-59 19 59	UG/M:	15.8 p	>16.8 p	N	28.05.96	07:31	40	Q
LR Nor	16 33 53.87	-56 28 03.0	UG	15.5 p	>17.0 p	N	28.05.96	06:25	60	Q
PG 1633+115	16 35 45.76	+11 24 57.7	cv:	14.9 B		N	28.05.96	02:36	50	Out ?
AC Sco	16 46 45.85	-27 24 27.0	UG:	12.5 p	>16. p	N	28.05.96	01:24	30	Q
HO Del	20 36 55.56	+14 03 08.5	UG	13.6 p	>17.2 p	N	31.05.96	07:53	60	Q

**Table 2:** Target objects without recorded spectra because at the time of our observations they were too faint. Type, Max and Min as listed by DS93. The scheme for spectral code (from DS93) is the same as in Table 1 (click here). Last column: magnitude of the object as estimated on deep white-light CCD exposures of the guiding system of the B&C spectrograph at the ESO 1.5 m telescope
Name			Type	Max	Min	Code	Date	UT	V
				(mag)	(mag)				(mag)
SV Ari	03 25 03.57	+19 49 53.9	n:	12. p	22. p	N	10.02.96	01:04	21
SZ For	03 41 19.96	-26 36 22.4	UG:	18.2 p	20.8 p	N	10.02.96	01:19	20.5
V701 Tau	03 44 00	+21 57 15	UG:	15.0 p	>21. p	N	10.02.96	01:12	22
V421 Tau	05 48 22.98	+22 42 01.2	ug	14.5 p	20. p	N	07.02.96	00:35	21
HM Gem	06 03 09	+25 14 49	UG:	16.5 p	20.5 p	N	07.02.96	00:58	20.5
V344 Ori	06 15 19.02	+15 30 58.6	UGZ	14.2 p	17.5:p	N	07.02.96	00:49	21.5
CI Gem	06 30 05.80	+22 18 56.6	ugsu:	14.7 p	18.5 p	N	07.02.96	00:41	20.5
NSV 3313	06 58 45	+17 02 11	n::	7.0 v	>14. p	D	08.02.96	01:12	22
EU CMa	07 05 41	-16 08 46	UG	16.5 p	>19. p	N	08.02.96	01:18	21.5
RX Vol	08 39 32.45	-66 17 40.1	UGSU:	16. p	>18. p	N	06.02.96	03:33	22
EG Cnc	08 43 04.12	+27 51 48.6	nl/ug:	11.9 v	17. :v	N	08.02.96	02:12	20.5
CT Hya	08 51 08	+03 08 32	UGSS	14.1 p	20. :p	N	06.02.96	03:53	21
SY Vol	08 53 28.96	-71 12 31.0	UG:	15.5 p	>17.5 p	N	06.02.96	03:38	20.5
CQ Vel	08 58 50.99	-53 20 17.8	na:	9.0 p	21. j	D	26.02.96	03:45	21
RX Cha	10 36 27.03	-80 02 52.4	UG	14.4 p	>16.9 p	N	07.02.96	05:17	22
MT Cen	11 44 00.74	-60 33 39.1	n:	8.4 p	22. j	N	09.02.96	02:40	22
V359 Cen	11 58 15.29	-41 46 07.9	n:	13.8 p	21.0 j	N	07.02.96	05:54	20.5
FU Com	12 30 51.60	+27 07 09.2	ug	19.5 p	21. :p	N	10.02.96	06:07	20.5
UZ Boo	14 44 01.45	+22 00 55.8	ugwz	11.5 v	20.4 V	N	28.05.96	03:13	21.5
AI Cir	14 49 31.29	-68 51 35.9	n:	10.9 p	23 j	D	28.05.96	03:20	21.5
PG 1617+150	16 19 51	+14 52 41	cv	15.0 B		N	28.05.96	02:00	21.5
V544 Her	16 38 05.48	+08 37 57.4	ug	14.5 p	20: p	N	28.05.96	08:00	22
V611 Her	16 44 52.16	+19 59 43.7	UG	15.4 p	>16.4 p	N	28.05.96	08:03	22
V840 Oph	16 54 44	-29 37 26	na:	6.5 p	20: j	D	28.05.96	01:50	21.5
V2276 Sgr	20 26 22.25	-43 40 33.0	UG	14.3 p	>16.7 p	N	31.05.96	07:14	21.5
AO Oct	21 05 08.35	-75 21 08.3	ugwz:	13.5 p	21 p	N	31.05.96	08:39	22
EH Aqr	23 34 06.66	-22 48 53.8	ug	17.5 p	>21.0 p	N	31.05.96	08:45	22

2. Observations