A bad or shaky condenser can cause plenty of problems with any circuit.

A condenser is a capacitor - a couple of plates separated by an insulator - it is essentially an open circuit that can hold a charge. If you take an old auto version apart, you will find two pieces or foil separated by something like wax paper, all rolled up to fit in the can. Modern condensers probably use better stuff. (I have taken bad components apart for 60 years or so - more people should do the same.)

If a condenser is shorted, the circuit is shorted - if the condenser "leaks" electricity, it represents a high resistance short circuit and some of the electricity goes someplace it should not. Old ignition systems cannot tolerate this.

The condenser is used to moderate large surges of current, making your points last longer. In the '50s people who kept their cars in fine tune adjusted their points every few months and changed them at least yearly.

If your points only switch a small trigger current, you do not need a condenser. If you use a condenser, make sure it is in proper condition. It is my opinion that they may not age well on the shelf - even a new one may be bad.

If you cannot find out how to test a condenser, I wish you luck changing your ignition system, you are going to need it!

I have a friend who builds hot rods, he uses ignition points on his builds because they will get you home.

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'96 855R,'64 PV544 driver, '67 P1800 basket case, '95 855, '95 854, the first three are mine, heh, heh, 485,000 miles put on 9 bricks