Re: Hyper-Cricket at 12 volts?


Kenneth Ketner
 

Did some additional tests with stock cricket recently built, no circuit changes. I fabricated a thin copper heatsink with about .5 x 1 inch surface area, formed its bottom around pa transistor, used some heat goo. With a battery reading 9 v open circuit, measured .7 watt out into oak hills qrp wattmeter with a dummy load. Checked temp of pa using a radio shack infrared no contact thermometer, got 79 f. Ambient temp of bench table read 77 f.

Next connected a lithium battery in 9 v box showing 10 v. Got 1 watt out. Temp at 82 f. Connected a battery of 8 1.5 v cells showing 11.5 v, got 1.5 w at 83 f. Pa not warm to touch. 

In the tests I sent some random key chatter into the dummy load for about 1 minute. 

It appears this particular gryllidae member can go with a standard shack 12 v supply, at least into a dummy load. Performance on air not tested yet. 

Would the increase in power cause failure of FCC emission standards?

Ken Ketner
KA5ELD
PO Box 65135
Lubbock, TX 79464-5135
Sent from my iPad

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