29-10-2016, 02:03 PM
I have finished the second table for the other Field. The interlaced circle looks pretty good. Photo taken below on a TV24.
The field blanking period needs some attention, I will look at that next.
A photo of a scan from the Oscilloscope also, which shows a lot of spikes on top of the video. I hadn't this problem with any of my other generators, I think it is most lightly caused by I using two sets of summing resistors in this one and one set is turning on before the other is fully off. The slew rate on the ports is configurable and by default is set to a slow setting to reduce RFI. I will set it to it's fast setting and see what happens, If no joy I will remove one set of resistors and use steering diodes instead.
When I get a frequency grating done up I will post that.
Frank
The field blanking period needs some attention, I will look at that next.
A photo of a scan from the Oscilloscope also, which shows a lot of spikes on top of the video. I hadn't this problem with any of my other generators, I think it is most lightly caused by I using two sets of summing resistors in this one and one set is turning on before the other is fully off. The slew rate on the ports is configurable and by default is set to a slow setting to reduce RFI. I will set it to it's fast setting and see what happens, If no joy I will remove one set of resistors and use steering diodes instead.
When I get a frequency grating done up I will post that.
Frank
