Just a guess, but check the biasing at each of the FETs. It's touchy.

What kind of working distance does it have? Is it enough to be able to do board rework while watching it?

I should really emphasize that I mean _nothing_ negative in my post. I got exactly what I "bargained" for and actually found it kind of amusing. I've ordered a couple of things from Han's since then,

A long time ago I ordered a spare micro for the QCX from Hans in case I did something bad during firmware updates and , being cheap, skipped the delivery tracking. No sign for a very long time and I p

Apologies if this is obvious, but the most common source of heat is the bias current being high. Do you have a reasonably accurate (plus or minus 5 mA) method of measuring and setting it?

#problem #pa

Thanks Allison. The plan is/was to use the amp for CW and PSK31 (no voice modes here) at around 10W out. My RXTX runs about 600 mW out. The amp was built for 20 mtrs, with the idea of adding an extern

Has anyone looked at the Zin over frequency? I built my copy for 20 meters and then looked at it with a nanoVNA. Swept from 3 to 28 MHz, it looks good on the receive path, but very reactive and much l

As a fan of "outside the box" style, you have my congratulations and admiration! Well conceived and implemented.

#qcx

Thought I'd share a couple of pictures of my take on an enclosure for the 50W amp. Standard 2020 aluminum extrusion and T nuts hold it together. End caps are #d printed. I'm leaving the ends open for

Yes, the buck converter is a cheap Chinese one with on-board display found on Amazon for about $6. I changed out the voltage adjust trimpot for a ten-turn off-board and added connectors: https://photo

Just another data point: I also used a LM2937 in place of the 7805. At 7.2V DC in, I get 500mW out on a QCX 40 mtr build. I use an adjustable buck converter to dial up the output power I want to run.

I kick myself for being an idiot and choosing the false economy of no-tracking for a spare QCX processor chip. When it never showed up, the last thing I was going to do is bug/blame Hans for it. I too

What band will you be on Robert? I'll be giving it a shot on 40, probably around 7.030 or 7.054.

#qcx

I hadn't really thought of it that way, but you're right. I retract the request and offer with apologies to Hans.

Does anyone have a link to a complete dimensional drawing for the case extrusion? I'll build a Fusion 360 model for 3D printing and upload it to the group if I can find one.

Would it be possible to add an edge mount SMA layout underneath the BNC?

To clarify, I don't use the decoder for normal reception. I'm trying to learn to send at higher speeds (30 wpm) and I find it a great way to evaluate the quality of my sending. I agree with all the fo

If I understand correctly, I should wait till the 7th to order. Correct? Can the e-book version be updated?

I just started the CWOps class and having the practice mode and decoder function of my QCX is a great asset. Thank you Hans for building this into the firmware!

One alternative might be to re-tune/re=program an existing 2.4 GHz RC down to the Amateur band of 2390 to 2450 MHz (1.2 cm). I have no idea if the existing frequency synthesizers can do that, but the

#rcvr #analog #avr #si5351b