Knight KG-687 Sweep/Marker Generator

[Notimetolooz]

I believe someone on the other forum suggested the point between C18 and R33. That seems reasonable. If you have a scope you can check, if the scope can display the frequency well enough. Also you could just try a makeshift connection to your counter. It would probably be a good idea to put a 100pf cap in series with the connection to the counter for DC blocking and isolation. If the signal is large enough, a 100 ohm resistor in series with the line to the BNC would help isolation also, so the counter doesn't load the marker so much it doesn't work right.