¿ªÔÆÌåÓý

ctrl + shift + ? for shortcuts
© 2025 Groups.io
  1. QRPLabs
  2. Messages
Single Messages Topics Expanded Polls

Re: QDX Query II #troubleshoot

 

¿ªÔÆÌåÓý

Thanks so much Hahns for that link.? I've been meaning to improve my understanding of this topic and you just handed me the tool to do it !? ?Much appreciated !
73 Phil WA8YAN




Sent from my Verizon, Samsung Galaxy smartphone


-------- Original message --------
From: Hans Summers <hans.summers@...>
Date: 12/20/21 8:16 AM (GMT-05:00)
Subject: Re: [QRPLabs] QDX Query II #troubleshoot

Hi Robbie, all

You divide by 100 if what you measured is V-Peak.?
You divide by 400 if what you measured is V-Peak-to-Peak.?

So the question all comes down to, did you measure V-Peak or V-Peak-to-Peak?

Also see my article: "The definitive guide to RF Power measurement"


73 Hans G0UPL

On Mon, Dec 20, 2021 at 4:12 PM Robbie M1ROK <me7rok@...> wrote:
I'm flummoxed as to where I got the 400 value from. I can only guess it's an errant value stored in my brain from when I did the full license exam at the end of last year. Oh well you learn from your mistakes...

Talking of those charts, they're even on the main QRP-Labs Dummy Load kit page too!

In other news that also means my 20m QCX is actually pushing out around 4.2W, and there's me thinking it was only doing 700mW lol.

You all have a great Christmas!

Robbie

On Mon, Dec 20, 2021 at 12:13 PM Alan G4ZFQ <alan4alan@...> wrote:
On 20/12/2021 11:35, Roger Hill wrote:
> If it is a Qrplabs dummy load, the manual says the formula is V-squared
> divided by 100, not 400. So you are getting about the correct 5 watts!

And, looking at the extremely fine manual I see two charts that save any
miscalculation errors:-)

73 Alan G4ZFQ
Join [email protected] to automatically receive all group messages.