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Miguel Lopez · 30th Jul 2012, 9:37 pm

Definitively the C1-94 is out of service. I had to dedicate a time to fix it (again).

The oscillator circuit work very good, giving a nice sine wave in the output winding. Initially it was tuned at 300kHz, but I think it is too high frecuency, and adding a capacitor to the grid circuit acroos the wnding conected to the grid, the frecuency fall to 40kHz. I still think that it is a very high frecuency.
What do you think?

The oscillator stopped working with a capacitor of around 0,1uF.

I'm thinking to make a 1/3 Hartley oscilator with an iron transformer in the non-tuned plate, working at 10kHz to get the desired voltage.

PS. I used a scope in my job to see the trace.

30th Jul 2012, 9:37 pm	#73
Miguel Lopez Heptode Join Date: Dec 2011 Location: Mayabeque, Cuba Posts: 617	Re: Building an oscilloscope at home Definitively the C1-94 is out of service. I had to dedicate a time to fix it (again). The oscillator circuit work very good, giving a nice sine wave in the output winding. Initially it was tuned at 300kHz, but I think it is too high frecuency, and adding a capacitor to the grid circuit acroos the wnding conected to the grid, the frecuency fall to 40kHz. I still think that it is a very high frecuency. What do you think? The oscillator stopped working with a capacitor of around 0,1uF. I'm thinking to make a 1/3 Hartley oscilator with an iron transformer in the non-tuned plate, working at 10kHz to get the desired voltage. PS. I used a scope in my job to see the trace. __________________ When electrons move, things happen. There's nothing you can do that can't be done.