Not necessarily. Check you S/N with respect to the mod install instructions. Wes N7WS

Except if you actually look at those instructions you'll see otherwise. "This modification applies only to K3S transceivers equipped with the KPA3A 100 watt power amplifier, serial numbers 10732 (fact

I sent a screen grab to your arrl address but I seem to remember they strip off attachments so you may not get it.

Except when it isn't. And in my experience, bipolar amps vary with frequency just like FETs. Wayne points out something that is totally ignored in these IMD discussions, but something I've mentioned s

If TX IMD is the issue, K3 and K3S transmitters are a real mixed bag. My old K3 at 30 watts is fantastic, with IMD at all frequencies better than -40 dBc (ARRL method). The same radio at 10W is the wo

I never said a word. But still on the subject of age, as I said I hit 78 on Saturday. We just porked up this weekend with steak, desserts and wine at fancy restaurants. But the Sunday before we did a

Nonsense. It's intellectual property that can/might be used in other Elecraft products. I turned 78 yesterday and I wish they would start shipping K4s soon so I can start my, "wait a year after delive

I don't see a K3 problem, I think it's a problem with one, or both, bypass relays (K20-K21) in the KAT500, although I suppose it could be any one of the relays. Wes N7WS

Quoting myself from a 2016 post: "I share your dismay. I was at Visalia once many years ago and looked at the then current K2. Cute little radio but I couldn't stand the feel of the tuning knob. This

Wow, where to begin. Of course you don't understand the personal ethics of some of us. That's okay, they are personal, some of us have them some of us don't. In what follows, I'm speaking as a DXer, c

Oops.

I haven't used the transverter output for anything, so have no experience. It does appear however, that there isn't any closed loop power control on that output. (If there is, I'm sure I'll hear about

Don't be ridiculous. We are talking about desktop equipment here. I have experience with liquid cooled transmitters dating from the 1960-1980s. AIM-54A Phoenix Missile used a silicon-based coolant tha

Unless you have a supply of distilled water that you can dump down the drain after it gets hot, then you have to cool it off by rejecting the heat someplace else; usually into the air. Then you've som

If it was there, I didn't catch it on the first round, but I'm really concerned that you claim operation down to 10 V. Have you looked at TX IMD at that supply voltage? Wes N7WS

Are you a doctor?

I have cautioned against running an LPA above 10W many times. Not for dissipation reasons (although there might be some) but because the IMD turns horrible above that level. Wes N7WS

Since it happens running only the LPA (5W cal failure) yet puts out 100 on the HPA on other bands, I doubt a P/S issue, but I wouldn't rule it out completely. I would be inclined to believe a LPA fail

Yes, I have asked repeatedly for VOX settings to be remembered by mode. Wes N7WS

Careful. Test mode doesn't survive a power cycle. Even if it did there is still signal from the TX that reaches the output. I have brought this to Wayne's attention and he informs me that the entire T