See the PB Control section of the manual menu table: "Selecting .01 kHz reduces the SHIFT range and disables HI CUT and LO CUT." 73, Scott K9MA

ESD to the USB port? 73, Scott K9MA

Does anyone know how to get the KAT500 to automatically put the K3 in the "Tune" mode (RF out) when the button on the KAT500 is pressed? I remember having this problem with the KPA1500, but fixed it s

Hi Martin, On the issue of receiver latency compromising QSK operation, I don't think the T/R switching necessarily introduces any significant latency. (My RJ-1 vacuum relay switches in 1.4 ms!) Recei

Hi Mike, There's no doubt that the crystal filters greatly improve the dynamic range of the K3. The dynamic range of the DSP is inherently limited by the resolution of the A/D converter, though they a

Hello Martin, I've been using QSK for many, many years, going back to the days of vacuum tube radios. The one thing that disappoints me about the K3 and other modern DSP radios is that the receiver la

If you look at the published curves for the two filters, you will see that the skirts of the narrow one aren't really much better than the wide one. So, even with the narrow filter, below 400 Hz, the

I also have those filters, but I wouldn't recommend the 250 Hz one. It really isn't much better than the 400 Hz one, by either Elecraft's published data or my own measurements. I think for those times

Sounds like a bad connection or contact between the antenna and radio. Relays are notorious for this. A little oxide builds up and blocks low-level currents. The high voltage on transmit breaks throug

The first thing that occurs to me is that something is going wrong with the antennas or feedlines at high power. Does the SWR go high in the OPER position at 100 W, or only at higher power? Does he ha

Brian, I suspect Elecraft decided they didn't need KL2 and KL3, which just switch in attenuation. I'm pretty sure the input to the KLPA3A should change with power setting, as there's nothing downstrea

Brian, Do you have an oscilloscope and some experience using it? Unlike a lot of modern radios, the K3 is really pretty easy to work on. With an oscilloscope, you should be able to look at the signal

I think the electronics and/or firmware associated with the recorders limits the rate. If you turn the knob too fast, the count doesn't change. I notice this particularly when trying to change the spa

L23 is in the 20/30m low pass filter. The only thing I can imagine could cause it to fail is a very badly mismatched load with just the wrong impedance. It's also possible, of course, that L23 was jus

There are a couple 15 V zener diodes across the supply line to provide protection (BZW50-15). They are specified to conduct less than 1 mA at 16.6 V, so 15.6 should be safe. However, Elecraft specifie

12.3 at 100W is definitely too low. 73, Scott K9MA

You did save your configuration files, right? 73, Scott K9MA

Never, EVER, connect your signal generator to the TX antenna jack! (Learned the hard way.) 73, Scott K9MA

Assuming the transmitter still works on 40, and the RX ANT switch is in the right position, the only thing that seems to make sense is that the control signal for the RX ANT relay is somehow in the wr

Thanks, Lyn. 73, Scott K9MA