With 13.0 volts at the input jack (from a bench supply), and 12.7 volts on
the circuit board's + bus, I am only reading 1.4 watts maximum power output into a 50 ohm dummy load. I haven't found a problem using the troubleshooting guide, voltages at Q1, Q4, Q5, and Q6 are where they are supposed to be. T1 and L3 look OK to me - but if I'm a sub-par winder can that lead to lower output? I have the resistors for the higher power output mod, but I'm trying to rule out build problems first. Any additional ideas? Thanks, Chip ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
With 13.0 volts at the input jack (from a bench supply), and 12.7 volts on the circuit board's + bus, I am only reading 1.4 watts maximum power output into a 50 ohm dummy load. I haven't found a problem using the troubleshooting guide, voltages at Q1, Q4, Q5, and Q6 are where they are supposed to be. T1 and L3 look OK to me - but if I'm a sub-par winder can that lead to lower output?
I have the resistors for the higher power output mod, but I'm trying to rule out build problems first. Any additional ideas? Thanks, Chip |
Chip,
What tools do you have available for measuring RF voltage? RF Probe, oscilloscope with 10X probe?, or none. How certain are you that your reference wattmeter is correct? Many can be in error by as much as 20% of the full scale reading. On a 20 watt scale, that is 4 watts - not very good when measuring QRP levels. I am not saying you do not have a problem, but if I am to help, I need to know the details about how you are doing the measurements. Do you have the KXB3080 installed? Please let me know your tools for measuring RF voltage and I can guide you further. If you have none, are you willing to build an RF probe? 73, Don W3FPR On 12/26/2010 6:47 PM, ae5ka wrote: > With 13.0 volts at the input jack (from a bench supply), and 12.7 volts on > the circuit board's + bus, I am only reading 1.4 watts maximum power output > into a 50 ohm dummy load. I haven't found a problem using the > troubleshooting guide, voltages at Q1, Q4, Q5, and Q6 are where they are > supposed to be. T1 and L3 look OK to me - but if I'm a sub-par winder can > that lead to lower output? > > I have the resistors for the higher power output mod, but I'm trying to rule > out build problems first. > > Any additional ideas? > > Thanks, > Chip Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Free forum by Nabble | Edit this page |