Re: Hyper-Cricket at 12 volts?2


I wonder if its a problem in the biasing of Q2. I assume the current draw went up a lot at 12 V causing the heating. I suspect it was not just the slight increase in power. The problem I see may be not so much someone trying to get more power output when using 12 (or 14) V in place of the 9 V battery but just not wanting to use (or having handy) a good 9 V battery. 

To be able to use 12 - 14 volts with the rig I would consider one of several methods. Changing the biasing (R6/R3) would perhaps work, but then if used at 9 V power out may be very low. One might try using a 9 volt regulator (7809) to power the whole rig from the higher voltage. Or one might try connecting R6 to regulated 9 V (zener circuit or real regulator) instead of the keyed 9 V line.

73/72 - Mike WA8BXN

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