[NewCandle] FYI

[Jones Beene]

Preliminary info from Mark Snoswell on Stiffler attempt:

Results with ferrite antenna transformer, 2 IN4148 diodes and LED. All 
tests done with "open air" circuit (no breadboard -- no capacitive metal 
anywhere close, no earth connections).

No problems getting LED to light.

Coupling from signal generator::
Presence (or absence) of series capacitor (470pf) or inductor 2,2uH in 
signal generator supply line make no difference to operation.

Diode type used for Avramenko Rectifier (AR)::
Testing several types of diodes suggests that diode capacitance needs to 
be low. Circuit worked poorly with ultra high speed power diodes (medium 
junction capacitance) and did not work with 200V schottkey (highest 
junction capacitance). These results suggest that low serial capacitance 
is required in the load for optimal output.

Capacitive load tests::
Placing series capacitance in the load dramatically reduces the output 
while placing parallel capacitance enhances the output. Parallel 
capacitance on the load does not effect the resonance frequency. 
Capacitance to ground on the load side enhances the output although the 
resonance is shifted to a lower frequency - as you would expect.

Load diode orientation::
Same operation with load LED in either orientation. Similar output power 
with two LED’s in parallel. No output with two LEDs parallel in opposing 
orientation. It appears that a polarized capacitive load is required for 
operation.

Preliminary finding on capacitive load::
Parallel capacitance is required on the load for function. This can be 
provided by capacitive coupling to ground or across the AV plug directly 
or via the junction capacitance of a load diode.

Square vs sine wave drive::
Both sine and square waves work just as well at the fundamental 
resonance. Square wave works better at sub-harmonic frequencies.

Principal resonances with no load to ground::
The fundamental resonance with no capacitive loading to ground (15ph 
scope probes) on the load was 12Mhz. Sub harmonics that give significant 
output are the 1/3 and 1/4. The principal frequency of 12Mhz gives the 
greatest output.

Principal resonances with load to ground::
With symmetrical 15pf load to ground on the output the principal 
resonance was reduced to 9.4 Mhz. Both 1/3 and 1/4 sub harmonics were 
present. The 1/4 frequency (2.34Mhz) now give the highest output. The 
waveform of the 2.34Mhz resonance is a rounded triangle wave indicating 
3rd harmonic (almost a text book example of triangle wave synthesis with 
first and third harmonic components). The principal resonance was 
observed directly and in ringing on square wave drive at lower 
frequencies. Measurements of the frequency on the ringing confirmed the 
presence of a single principal resonant mode.

Load waveforms::
At all times the signals on the load were in phase but had a DC offset.

Single and double ended drive::
The circuit works similarly with single or double ended drive to the 
primary.

All tests were done with a HP33120A signal generator (10 Vp-p output). 
Measurements were made with Tektronix TAS 475 scope (100MHz 4 trace). 
Unless indicated otherwise all scope measurements were done with 10X 
scope probes with tips held close to leads to eliminate load effects on 
the measured circuit.

The next tests will look at antenna transformer – number and direction 
of turns in the primary and secondary and alternate cores. I will also 
measure the Q of the principal resonance. Load tests will look at 
inductive influences.