Coaxial connectors selection guidance
For the majority of co-axial connectors, it is critical to have a connector that is specific to the cable to be used. Most connector manufacturers use a cable group coding system, but they are all different, as might be expected. Since a substantial number of Canford’s range of co-axial cables were BBC designs, it is logical therefore to use the BBC’s own classification, extended to cover designs from Canford’s own range.
When ordering connectors, find the cable being used in the chart below. This indicates a group type reference, which is used in most connector descriptions. However, it is essential to check that the correct crimp die is being used when making crimp terminations. Because there are small detail variations in similar connectors from each manufacturer, different crimp dies may be needed. A similar looking connector from another manufacturer, on the same size cable, does not guarantee that the crimp die regularly used will still work.
See the crimp die selection chart for suitable dies for every combination of cable and connector stocked by Canford.
Cable group |
Cable types |
Overall diameter |
Dielectric diameter |
Impedance |
A |
VCL (BBC PSF1/2) |
7.5 |
4.9 |
75 |
B |
VCS (BBC PSF1/3), VCF |
6.5 |
3.75 |
75 |
C |
RCH (BBC PSF1/4), RG213, URM67 |
10.55 |
7.4 |
50 |
D |
RCM (BBC PSF1/6) |
5.2 |
3.1 |
50 |
F |
RG174U |
3.0 |
1.6 |
50 |
G |
URM43 |
5.15 |
3.1 |
50 |
H |
RG11, CT167, CX167, URM57 |
10.55 |
7.4 |
75 |
J |
S-VHS, URM111, RG179B/U, Belden 179DT |
2.6 |
1.6 |
75 |
L |
VCM, VFM, CVC3, CVC4, CVC5, CVA32 |
3.7 |
2.32 |
75 |
Q |
SDV-I, RG59, Belden 1505A, 1505F |
6.15 |
3.7 |
75 |
R |
CT125, CX125, URM203 |
7.5 |
5.25 |
75 |
V |
RG58 |
4.6 |
2.5 |
50 |
W |
SDV-M |
3.1 |
1.9 |
75 |
X |
SDV, SDV-X, Belden 1855A, 1855ENH |
4.5 |
2.8 |
75 |
Y |
SDV-L, SDV-F, Belden 1694A, 1695A, RG6, CT100, CX100 |
6.8 |
4.8 |
75 |
Z |
SDV-HD, Belden 7731A |
10.16 |
7.11 |
75 |