[Amps] Peak Reading Addon For Wattmeters...

[KB0NLY]

Anyone know a proven design/schematic freely available on the net for building a peak reading circuit into a regular average reading wattmeter?

My HF meter has a HI-Res PDC-1 that i bought and built from a kit, but i'm looking for other options now as that one has been giving me fits lately.  Some days it works, some it doesn't, it has a real mind of its own for some reason.  Not to mention that it won't run on anything but a 9v battery and i'm getting tired of buying those spendy little buggers.  

By the way, if anyone is familiar with the PDC-1 can you tell me why it won't work on anything other than a battery?  I tried a wall adapter, running it off the shack power supply, you name it.  If you run it off anything other than a battery the needle jumps up and then drops on transmit never indicating how much power was going through.  I think maybe its RF getting into the board and plan on trying some bypass caps on the power wiring to it, maybe a choke also.

73,

Scott