Yes, it's 15 dB transfer loss. It's due to the choice of voltage dividing resistors in the J310 source follower stage.
Half or a bit more of the loss can be offset with a change in the parts values in the voltage divider feeding the gate. Another option is an outboard amplifier such as the Z10000 I've designed. Jack K8ZOA www.cliftonlaboratories.com Don Nelson wrote: > Hi all, > > I am wanting to use the IF output on the K3 with the installed KVX3 board. My > problem is knowing what I need to administer to activate the IF output port. > > With the K3 as is, I put a 14.270 MHz RF signal into the ANT1 port on the K3. > The 14 MHz signal is from an HP 8640 at -120 dBm. The K3 is set to use ANT1. > I connect the IF output from the K3 into an HP spectrum analyzer and see no > signal at 8.215 MHz. The K3 is tuned to 14.270 MHz USB. So I put Mini > Circuits amplifiers with 50 dB total gain between the K3 IF output and the > spectrum analyzer. With the amplifiers in the path, I see a signal at – 85 > dBm which suggests a signal out of the K3 on the IF output of -135 dBm. If I > increase the 14.270 MHz signal by 10 dB I see a 10 dB increase in signal out > of the IF output port. > > Is this right? I would expect a signal out of the IF output with much greater > signal strength. In essence, there is a 15 dB loss in the signal path from > the antenna jack to the IF output port in my K3 as configured. Is this > correct? Is there something I need to administer? Where is this documented? > > Thank you for your help. > > Don, N0YE > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
