Haken, At this point, do not be concerned about those voltages you found did not agree with the chart in the manual.
The no voltages at the diodes is a cause for concern. The problem may be in where you measured for voltage or the settings you were using. We will get to that. Let's verify that the source for the diode switching voltages are correct: First thing, set the SSB FL1 filter to OP1 (using the K2 menu). Set the K2 to SSB mode and be certain FL1 is selected. Now measure the voltage at U1 pin 21 (should be about 6 volts), and measure the voltage at U1 pin 22 (should be near zero volts). Now, switch to CW mode (any of the CW filters is OK), and measure the voltage at U1 pin 21 (should now be near zero volts) and U1 pin 22 (should now be near 6 volts). You should also find about 6 volts at the cathode of D7 and D8 and at the cahode of D11 and D12. If you do not have these voltages present, check to be certain RFC1 and RFC2 are not shorting to the crystal cases (insert a sheet of paper between the choke and the crystal as an insulator). If all the checks above are correct, switch back to SSB mode, FL1 (OP1) filter and check for about 6 volts at the cathode of D6 and D9 and at the cathode of D10, D13 and D14. If you find all those voltages correct, the filters should switch between the CW filter and the SSB filter. Just as information if you are following the schematic - the RXC signal indicates that receive should be through the CW filter when this signal is active (about 6 volts), and RXS indicates that the receive path is through the SSB filter when this signal is active. Make the checks above, and if that did not lead you to fine the source of the problem, send us your report of your findings. 73, Don W3FPR > -----Original Message----- > > I have just put together the KSB2 SSB ADAPTER and I have problems. > > Referring to the manual on page 15 “Initial Test” the last paragraph > “Verify that the K2 performs...” I do not get any sound in the > loudspeaker, or the sound I get is very very muted. I can hear some very > faint - both CW and SSB – signals but only when the volume is turned up > to max. > > Else there is no problem doing the “BFO Test”, “Receive-Mode SSB Filter > Test” and “BFO Setup for LSB/USB” > > I have checked the voltages as seen on page 23 in the manual and found > the following anomalies in receive mode: > > U1-21... zero volt (should be 5.8) > U2-5.... 6.0 volt (should be 0.6) > U4-3.... 6.0 volt (should be 0.6) > > D10-D13 and D6-D9... no voltage in receive mode. > > So, what could be the matter? > > 73 de > Håkan / SM6EQO > -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.432 / Virus Database: 268.15.28/605 - Release Date: 12/27/2006 12:21 PM _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com