And so it begins...

[moorejl57]

I assume you're building the REV-E version. In which case, TP9 and TP10 should be close to 10us (or maybe slightly higher due to the two diodes), and the EFE delay should be 100us.

OK, thanks, I will check the schematic vs. parts loaded and see if I can find anything out of place. I tested every component with a LCR meter before loading, but I didn't test any of the diodes. I didn't find any components that were noticeably out of spec.

[Qiaozhi]

On stage 6, I am getting a short EFE pulse width (63us) at TP8. Is this an issue or within normal variation? TP9 and TP10 seem in the ballpark at 7.2us each.

[ATTACH]46355[/ATTACH] [ATTACH]46357[/ATTACH] [ATTACH]46356[/ATTACH]

I assume you're building the REV-E version. In which case, TP9 and TP10 should be close to 10us (or maybe slightly higher due to the two diodes), and the EFE delay should be 100us.

[moorejl57]

On stage 6, I am getting a short EFE pulse width (63us) at TP8. Is this an issue or within normal variation? TP9 and TP10 seem in the ballpark at 7.2us each.

[moorejl57]

The noise level looks ok. If you change the orientation of the coil you should see the noise level change, indicating that it's externally generated.

Great, thanks for the reassurance. I was also having a senior moment and realized I hadn't connected the shield to the coil yet and I am in a noisy environment. Other than dropping parts on the floor and then not able to find them, the build has been going smoothly.

[Qiaozhi]

Stage 5 waveform at TP3, does the noise level look normal?

The noise level looks ok. If you change the orientation of the coil you should see the noise level change, indicating that it's externally generated.

[moorejl57]

Stage 5 waveform at TP3, does the noise level look normal?

[moorejl57]

OK, I am passing stage 4

Flyback well over 350V, hard to measure but probably around 450V. Still have an intermittent jitter on TX oscillator period.

[moorejl57]

New question:



On stage 3, while installing components
1. C22 is ceramic disk vs. little white box type, not trying to nitpick, just want to verify substitution is OK

On stage 3, while adjusting TX pulse period and width, are these normal expected observations
1. set pulse period first, while setting pulse width observed that pulse period is also changing (settings are interacting)
2. pulse period is not completely stable (varying at a relatively slow rate (slow period jitter)

[moorejl57]

Just use a voltage divider across coil

Seems like this could work as well, thanks.

[moorejl57]

flyback voltage is almost sure same. you will see a current. put a resistor between the coil and +9V. put gnd cold end of the probe on +9V, hot end on the
joint resistor-coil.

Oh, I understand what you mean, measure the smaller voltage across the series resistor, thanks.

[kt315]

So you are suggesting that I limit the current and magnetic field with a series resistor such that the flyback voltage is smaller and then safe for my scope. Sounds like a reasonable alternative, thanks for the input.

flyback voltage is almost sure same. you will see a current. put a resistor between the coil and +9V. put gnd cold end of the probe on +9V, hot end on the
joint resistor-coil.

[6666]

Just use a voltage divider across coil

[moorejl57]

So you are suggesting that I limit the current and magnetic field with a series resistor such that the flyback voltage is smaller and then safe for my scope. Sounds like a reasonable alternative, thanks for the input.

[kt315]

guys do suggestion of Eric where he wrote to put a resistor 1Ohm in serial to coil and look a picture on it.
thats enough and you do not need setting x10. just read all that Eric had wrote.

[moorejl57]

Thanks everyone for the advice, I will be sure to use the 10X setting.