Tuesday, March 19, 2013
A recent e-mail got me thinking about Doug DeMaw's Barebones Superhet. June 1982 QST. Mostly 40673 Dual Gate MOSFETS (this one's for you Dino!). Barebones indeed. Check out the schematic.
I literally blew the dust off my version and fired it up on Sunday. It sounds really great. I had lowered the values of the caps in the ladder filter to widen it out for phone. Also, I see that I used LM386 instead of the op amp AF Amp prescribed by W1FB. I notice that my version has much better audio than another version of this RX (with the op amp) that I'm using on 17 meters. Could the difference be the LM386 vs. op amp? There is a lot more audio with the 386, and the AF response seems wider.
I feel the urge to put this receiver to use. I am rehabilitating the W1VD CW transmitter that used with it during the late nineties, but I'm a phone guy now, and I feel compelled to use this RX as part of an SSB rig. Of course, I could build a standalone SSB TX, but how about a diode switching scheme to make use of the Barebones' filter, the VXO and the BFO in a transceiver?
Here is my article on the original build of this receiver: http://www.gadgeteer.us/HBHOME.HTM
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