We had 2 instances of A.I. project help this time. Art KD6MSA (from BA) welds specialty metals. He asked ‘Google’ how to make a 440 J-Pole using 3/32 in Silicon Bronze wire, and got detailed advice. Cutting one side at 6.45 in and the other 19.30 in, he welded them to a bottom plate (so it looks like an Arrow aluminum J-Pole. The other A.I. was Tom WA5MAZ’s side hustle fixing Hammond organs, in this case actually the ‘Leslie’ speaker that makes the output ‘warble’. He made a solid state substitute for the motor driver (to turn the speaker baffle around), and got a 1500 line code from ‘Claude’ that gave the proper commands to the CPU driving three 14 Amp Mosfets (for the 3 phase motor).
In the pic above are various ckt boards Tom MAZ made, along with a power drill from Earl WB5UUW (who lives in Glenpool). The drill has a built in flashlight (not so unusual) but when you tilt it left or right, the motor turns (either to loosen or tighten a screw). It’ll also turn a drill bit. Earl also brought in a Triplett brand meter in a leather case, but we never did measure and compare all the meters.
Ron N5NZL had the fanciest Show ‘n Tell, a home made 2 element directional beam (sized for 220) that works well from 2M to 440 (and it’s foldable). He won the Fanciest S ‘n T prize, a combination ball point and flashlight pen.
Notice the mech detail first, foldable elements etc, and then the attenuator (20, 10, 5, 3, 1 dB), and a phone for magnetic heading, and of course a dual band Baofeng to receive. (de Ron N5NZL)
Mike KI5YX, as he often does, brought in his Tiny SA Spectrum Analyzer and dummy load, and tested Art MSA’s Baofeng. Sure enough, the 2nd harmonic of the 2M output was ‘only’ 32 dB down, not 40 as required. (it’s only 1/1000th of the output, not a 10,000th) The 440 2nd out was undiscernible.
The main program was supposed to be about transitor gain (hfe) and meters, and Rich ZQG did use his Radio Shack Simpson 260 lookalike in the Ohms position to forward bias an NPN transistor. (The old analog meters (in Ohms functions) usually put out Positive current on the Black probe (yes i know that sounds backwards) and put out different amounts of current for each Ohms scale. Rich used the scale that puts out 2 mA to forward bias both a TO-5 cased NPN and then a TO-3 cased 2N5686. They each drew (a measured) 300 mA of collector current. Then he used the Rx10 scale to put out 20 mA and, using the 5686, saw it’s collector current go to 3 Amps. Knowing what would happen, Rich only did it sparingly so the 5686 in the diamond shaped T0-3 case only got uncomfortably warm. New Ham Blake KJ5PMU said, Hey, this is a fun club. Do you do this every month. How much are the dues. We kind of ignored the question. Deb K5DBE and Sam KJ5BJR brought in their Cen-Tech digital multi meter, but as noted, we never got around to checking all the meters. The Cen-Tech, origianlly $4 from Harbor Freight, and then $7.99 under Biden, is no longer sold. An updated version is, like, 20 bucks at Harbor Freight. It puts out positive 0.3 Volts on most of the Ohms ranges, and 2.7 Volts on the Diode function and 200 Ohms range, so yes you can use it to forward bias a junction, but like any digital display you have to read the value and then interpret what it means rather than just easily view the angle of meter swing to immediately get an idea of how much current you’re using to (in this case) forward bias the transistor.
Next mtg is 2nd Thurs, 12 November, 7PM at Scott’s hamburgers Party Room (in Bixby) and then the 4th Thurs, same place. Remember, No dues, No business meeting, and a Tech program every mo.
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