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Old 11-24-2009, 07:21 PM
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FuzzyTomCat FuzzyTomCat is offline
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Test #11

Hi everyone,

I did a short test using a new replication of the "Quantum" October 2002 Load Resistor, as per some revised specifications from Harvey and Rosie with a 32mm x 254mm coil on a 280mm piece of "Borosilicate" glass tubing and a calculated inductance of 8.64 uH @ 48 turns of 22AWG Ni Cr type A wire.

The results were somewhat expected with the Mosfet Drain spikes (Channel-2) smaller in amplitude but the battery spikes (Channel-4) remained the same, the Channel-1 mV readings were much larger than a normal running at the frequency that I'm usually operating at. The Load resistor temperature was between 110 and 140 degrees F a normal range, and the Mosfet was running at 200 to 260 degrees F much higher than normal.

I was also refining the gate pot type for publication and am going to wind another load resistor coil for a comparison between my original prototype resistor with the same center to center coil wire spacing but using the "HUGE" 76mm "Borosilicate" glass 6 inch long tubing shown in the set-up photograph.




************************************************** ******
Rosemary Ainslie COP>17 Heater Circuit
"Quantum" October 2002

Replication Components -

1) International Rectifier - IRFPG50 HEXFET® Power MOSFET
w/ Sil-Pad insulator between Mosfet and Heat Sink

2) Fairchild Semiconductor - NE555N Timer

3) Vishay Spectrol - SP534 Percision Potentiometer/ 10-turn 2-Watt

4) Exide Technologies Battery "Liquid Lead Acid" Model # GT-H - TRACTOR 12V 12Ah CCA 235

5) CSB Battery Company "Gel Lead Acid" #GP 1270 F2 / 12 Volt 7.0 Ah

6) Prototype "Quantum" Load Resister 10 ohm 32mm x 254mm

7) "Shunt" - Caddock High Performance Film Resistor "non-inductive" 30 watt type MP930-0.25-1%


************************************************** *******

Channel 1 - Mosfet source shunt
Channel 2 - Mosfet drain
Channel 3 - 555 Timer pin #3
Channel 4 - 24 VDC "Liquid" Lead Acid Battery Bank


TEST #11 - Complete Original Image & Data .Zip File Set

40us


20us


2us


100ns


Channel-1


Channel-2


Channel-3


Channel-4



All Images and data by a Tektronix TDS 3054C from the Tektronix Corporation


Glen
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Last edited by FuzzyTomCat; 11-28-2009 at 11:01 AM. Reason: grammer - added TEST #11 .zip File