Oak Hills Research WM-2 QRP Wattmeter

This kit is suitable for most beginners, as the instructions are extremely basic and leave no stone unturned. Calibration is simple, and as most hams say--this piece of equipment is essential to any QRP experimenter's shack.
____NOTE___ I made a mistake with the jumper JP1. I thought "Jumper" was actually JP1, so after calibrating I removed "Jumper" and left JP1 intact. Hm. Scratch head, calibrate again. Same results, scratch head... Go back and read instructions carefully... Ha ha, I caught my error. Actually getting exactly the right voltages on the trimpots is trickier than anticipated. They are quite pressure-sensitive and touchy. Like the Elecraft T1 or other 'semi-factory' kits, this has the look of a piece of commercial gear when finished. Even though I flubbed up the front panel and had to partially peel it up to move it over 1-2mm, it doesn't show on the finished product. I'll be very glad to go back and check the power output of previously built QRP radios, and calibrate other power meters I've made. This one's considered the QRP shack standard. I'm happy I built it.
-7J1AWL/KC7FYS
PS. The music and crying baby are added bonuses in this video, ha ha.

Category:

People & Blogs

Tags:

• QRP
• WM-2
• WM2
• Oak
• Hills
• Research
• Wattmeter
• KC7FYS

[iw3fzq]

Hi Jonathan, thanks for have replied but... KD1JV SWR/Power meter with 5% accuracy with led ???? How is it possible ?? I don't like it, I prefer a taditional needle meter.

73 de Enrico, IW3FZQ

[kc7fys]

Then I recommend the NoGAWatt. This is a small Altoids-sized fwd/rev power meter for a small budget. It's not super accurate, but fun to build.

The WM2 is the standard, as far as I can tell, for those unable to homebrew their own power meter. KD1JV's device has served me well in the field when I want to know if my equipment is putting out generally what it usually does.

[iw3fzq]

Good job! In your opinion, is this item a good meter for QRP or it isn't accuracy?

73 de Enrico, IW3FZQ

[kc7fys]

I don't know it's accuracy exactly, but most consider it the standard for the QRP builder. It is easy to use, easy to build, and looks great on the bench. It is not portable, however, if you are looking for a rugged field meter. I recommend the KD1JV QRP SWR/Power meter kit for that. It's cheap and rugged--but not as easy to read as the WM2. I hope this answers your question.

[DisabilityFraudKJW]

Is that David Arch singing in the background?

[rothschadel]

this saved me a lot of headache! Watching your video helped me spot my mistake. Thanks loads!

[sp4ndq]

Congatulation, nice works...73 de Marek SP4NDQ

[sp4ndq]

Nice works, congratulation ...