Hardrock-50 HF Amplifier Power Output

1.8w = 50w on meter
Shows 55w on screen
Input SWR = 1.3:1

2.6w = 50w on meter
Shows 55w on screen
Input SWR = 1.2:1

2.6w = 50w on meter
Shows 55w on screen
Input SWR = 1.3:1

5w = 50w on meter
Shows 54w on screen
Input SWR = 1.4:1

3.2w = 50w on meter
Shows 55w on screen
Input SWR = 1.5:1

4.2w = 50w on meter
Shows 55w on screen
Input SWR = 1.8:1

3.4w = 50W on meter
Shows 55W on screen
Input SWR = 1.9:1

5w = 30w on meter
Shows 35w on screen
Input SWR = 4.6:1

Hardrock-50 HF Amplifier Build Complete!

Today I finished building my Hardrock-50 50w HF Amplifier kit. It was pretty-much done yesterday, but needed a few final tweaks to complete.

I haven’t photographed every stage of the build process, but I’m sure you’ll get the gist of it! Apologies for the quality of these photos too… I was in solder-mode rather than photography-mode, so they’re not well lit or composed I’m afraid.

Continuing on from my previous blog post, I started by winding the torroids. My fingers hurt after doing these, and working with PTFE covered wire is a pain in the bum! There’s a fella in the US that can sell you a complete set of pre-wound torroids for a nominal fee, but where’s the fun in that?


Next was soldering the metal stand-offs to the main board which was easy:


Here you can see the bottom of the main board after I had soldered in all the through-hole components:


And here is the top of the main board. A couple of the torroids were really fiddly to attach.


This is the main board attached to the heatsink with the front and rear panels connected. The only big problem I had was that I snapped the drill bit while drilling the second to last hole, so the main board is only attached at the rear (but it isn’t going anywhere!)


Here it is, alive!


This photo shows me on the air with it for the first time last night:


I’ll write another quick blog post later on showing the amplifier case in more detail and along side my Elecraft KX-3 (my photos haven’t synced via iCloud yet!)



Hardrock-50 HF Amplifier Build – Day One


Today I started to build my Hardrock-50 (HR-50) HF Amplifier Kit, which I got for Christmas from my Mum and myself.

The first thing to do was to replace two SMD capacitors on the main board (C5 and C31) because the factory installed incorrectly rated parts.

I can’t remember ever replacing any SMD components before, so this was quite unnerving; however once I got the main board into my PCB holder, fired up the Weller and found my wife’s tweezers from the bathroom, I was all set and didn’t find it too difficult after all.


Next I fired up the PDF manual on my computer and started following the steps to the letter!

First up was the front panel with the LCD and buttons. This was pretty straightforward. The header pins were pretty close together and the rings to solder to on the PCB are minute, but it didn’t take long to complete.




Next up was the rear panel, which was more straightforward and didn’t take long to complete. I guess the SO239 sockets and Anderson Power-Pole socket will be installed later.



That’s it for today… Next stop torroid / inductor winding! I want to get rid of this flu virus entirely before attempting those!

Cheers, Josh!