Table 3: Comparison of the observational characteristics of the four new CVs. The (non)detection of X-ray emission refers to the ROSAT All Sky Survey (Voges et al. 2000). The CV subtypes are abbreviated as UX = UX UMa type novalike variable, ZC = Z Cam type dwarf nova, VY = VY Scl star.
Object $P_{\rm orb}$ Radial velocity Photometric variability X-ray type

[min] variation Orbital Flickering Long-term

HS 0139+0559 243.7 clean, moderate amplitude none none none no UX or ZC

HS 0229+8016 232.6 clean, large amplitude very low amplitude none $\sim$ 1.3 mag no UX or ZC

HS 0506+7725 212.7 scatter, low amplitude not obvious large amplitude $\sim$ 3 mag low state yes VY

HS 0642+5049 225.9 very low amplitude moderate amplitude low amplitude none maybe UX or ZC

**Table 3:** Comparison of the observational characteristics of the four new CVs. The (non)detection of X-ray emission refers to the ROSAT All Sky Survey (Voges et al. 2000). The CV subtypes are abbreviated as UX = UX UMa type novalike variable, ZC = Z Cam type dwarf nova, VY = VY Scl star.
Object	$P_{\rm orb}$	Radial velocity	Photometric variability	X-ray	type
	[min]	variation	Orbital	Flickering	Long-term
HS 0139+0559	243.7	clean, moderate amplitude	none	none	none	no	UX or ZC
HS 0229+8016	232.6	clean, large amplitude	very low amplitude	none	$\sim$ 1.3 mag	no	UX or ZC
HS 0506+7725	212.7	scatter, low amplitude	not obvious	large amplitude	$\sim$ 3 mag low state	yes	VY
HS 0642+5049	225.9	very low amplitude	moderate amplitude	low amplitude	none	maybe	UX or ZC

Source LaTeX | All tables | In the text

	1 Introduction
	2 CVs in the Hamburg Quasar Survey
	3 Observations and data reduction
	4 Analysis
	5 Discussion
	6 Conclusions
	References
	Online Material