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See_Mos · 10th Oct 2018, 10:24 am

Sorry, but I have to agree with David, the only way you could achieve a display like that on a single trace would be if the timebase was syncing on both positive and negative excursions and very close to the zero crossing point so that you are in fact seeing two traces one after the other.

Now, "The problem I have now is the problem with the input levels jumping up"

Is this indicated on the meter and is it going over scale or back to zero?

Try scoping at the preset resistors R112 and R212 as you increase the levels.

Interestingly the two circuits I have show different values for the front panel record level pots, either 1meg with one end not connected or 25K with all three connections used.

10th Oct 2018, 10:24 am	#17
See_Mos Hexode Join Date: Nov 2003 Location: Ossett, West Yorkshire, UK. Posts: 483	Re: Tandberg 3000x annoying problem Sorry, but I have to agree with David, the only way you could achieve a display like that on a single trace would be if the timebase was syncing on both positive and negative excursions and very close to the zero crossing point so that you are in fact seeing two traces one after the other. Now, "The problem I have now is the problem with the input levels jumping up" Is this indicated on the meter and is it going over scale or back to zero? Try scoping at the preset resistors R112 and R212 as you increase the levels. Interestingly the two circuits I have show different values for the front panel record level pots, either 1meg with one end not connected or 25K with all three connections used. Last edited by See_Mos; 10th Oct 2018 at 10:30 am.