Re: 120bps vs 240bps tests
Hi John, Malcolm, and all,
John Freau wrote:-
> I performed the tests suggested by Malcolm. Here are the results:
> (note: all tests done at 120bps) Table at end of post.....
> BPS Div meter W toroid Cp(uF) spark
> 120 3.6 220 10" .0077 17"
> 120 5.0 440 26 .0077 22 30% increase
> 120 5.0 430 10 .0077 26 mult. streamer
> 120 3.6 320 26 .0147 22
> Comments welcomed,
> John Freau
More excellent test results, I really wish I had time to take more
measurements. I found that by using a HV scope it was easier to
figure out what was going on in the rotary with different caps
and HV supplies.
Your results seem pretty conclusive that 120BPS sync is better
than 240 BPS sync for best spark length. Also you seem to be saying
that power is still processed into "Cap Energy" efficiently at
240BPS if I understood you correctly. Therefore it must be the
spark that does not grow as well at 240 BPS as we had hoped ?
I plan to do some low power tests using around 300Watts at both
100BPS and 200BPS with all other parameters constant. V will
obviously by 1.41 times higher at 100BPS to get the same power.
That is why I am keeping the power low to save the caps.
I will keep the list posted.
I can adjust the phase of my 200BPS gap so that it only fires on
alternate presentations, ie. at 100BPS. Funny enough, this also
seems to be very close to the best firing angle for a purpose built
100BPS gap ! This is fortunate as I can compare 100BPS and 200BPS
just by adjusting the phase of the gap. Have you tried this ?
Note: 100BPS and 200BPS refer to synchronous operation at 50Hz (UK)
120BPS and 240BPS refer to synchronous operation at 60Hz (USA)
Keep the info coming,
- In sunny Newcastle.