Problem solved- bad quality connectors.
In the microwave business people often replace the last four letters of Pasternack with something less polite.
BNCs are rated for use up to 4 GHz (1.5 GHz for 75 Ohm types). However, there is a price to be paid for the quick connect feature- risk of incomplete contact of the outer, if there is sideways pressure on the plug.
RF leakage is then poor and a suck-out in transmission performance can occur.
In equipment that does not get moved around much I would use BNCs up to 1,296 MHz. For /P equipment, not above 450 MHz.
I think that the old RS BNC connectors were made by TE Connectivity (was Greenpar), first in Harlow, later in Taiwan. Tyco have moved production of this line to China and the current types supplied to the old TE part numbers bear no resemblance to the original drawings.
I do not know where RS currently source their own brand connectors from, but careful testing would be wise.
Alwyn Seeds, Director
114 Beaufort Street,
SynOptika Ltd., Registered in England and Wales: No. 04606737
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