It's hard to tell from the picture, but it doesn't look like you built it all through the final audio output transistors. Did you omit Q8, Q9, R32, and R33, per the text of the article for use "for portable operation with low impedance headphones?" Is that correct? Thanks for clarifying.
the output transistors are heatsinked by an aluminum lid...with wires connecting them both to the circuit board...you can see the bottom part of the lid with the wires between it and the circuit board on the main vid pic...
@dl6urk looks like its not available anymore on the KANGA site...not sure if anyone else has taken up the cause...there is this however...first i've seen it though.. qrp-popcorn.blogspot.com/2014/10/simpler-single-signal-direct-conversion.html
@dl6urk I have done this in the past with the KK7B and have noticed that the KK7B usually needed a pre-amp to pick up the same weak signals as commercial RIG(s)...i have also used the KK7B as a 2nd rig for RX ONLY FULL QSK BREAK IN QRQcw mode using a homebrew PIN DIODE T/R switch...it was just a lot of work if you wanted to change frequencies since the TRANSMIT ONLY commercial RIG and the KK7B RECEIVE ONLY rig are not synced...all in all though, the KK7B, even having 2 signals to deal with, being only a DC RX, is a fine RECEIVER, if you don't mind not having AGC on strong signals....it has enough audio amp power to get pretty loud
I am building a 30 meter QRP CW rig now using the R1 board. Thanks for this video!
It's hard to tell from the picture, but it doesn't look like you built it all through the final audio output transistors. Did you omit Q8, Q9, R32, and R33, per the text of the article for use "for portable operation with low impedance headphones?" Is that correct? Thanks for clarifying.
the output transistors are heatsinked by an aluminum lid...with wires connecting them both to the circuit board...you can see the bottom part of the lid with the wires between it and the circuit board on the main vid pic...
Unfortunately, there is probably no commercial PCB left, right?
@dl6urk looks like its not available anymore on the KANGA site...not sure if anyone else has taken up the cause...there is this however...first i've seen it though.. qrp-popcorn.blogspot.com/2014/10/simpler-single-signal-direct-conversion.html
I believe the pcb artwork was in a few of the ARRL handbooks, with the art work in hand OSH PARK would at fairly reasonable cost whip up a few.
A comparison between your K3s and this historical DC Receiver at the same BW would be interesting ;)
@dl6urk I have done this in the past with the KK7B and have noticed that the KK7B usually needed a pre-amp to pick up the same weak signals as commercial RIG(s)...i have also used the KK7B as a 2nd rig for RX ONLY FULL QSK BREAK IN QRQcw mode using a homebrew PIN DIODE T/R switch...it was just a lot of work if you wanted to change frequencies since the TRANSMIT ONLY commercial RIG and the KK7B RECEIVE ONLY rig are not synced...all in all though, the KK7B, even having 2 signals to deal with, being only a DC RX, is a fine RECEIVER, if you don't mind not having AGC on strong signals....it has enough audio amp power to get pretty loud