Radio Preppers

General Category => Technical Corner => Topic started by: RadioRay on May 08, 2013, 09:55:09 PM

Title: Amplifier for Use With QRP Rigs
Post by: RadioRay on May 08, 2013, 09:55:09 PM
I have been slowly working through some 'bugs' on my homebrew amplifier.  It looks like it is alive and STABLE.  I'll save the boring parts, but it was unstable above about 50 Watts.  In the application notes, there was a small entry stating that because of the HIGH gain of this amplifier, it is advisable to separate the input coax from the output.  Welllll DUH!  Ya' think?  Due to the small size of my 'shack' all coax goes into a common 'well' in the wall, between the 2x4's to save space.  After making it all neat tidy and segregated, the amp is now able to run at 140-150 Watts for my QRP rig's input of 1-2 Watts.  It looks better when it's neat and tidy too!

The amplifier components and PCB are available from Communications Concepts Inc.  Mine is the EB63A



>Ray


Ps. Now to make output filters for the other bands.

Title: Re: Amplifier for Use With QRP Rigs
Post by: Joe on May 08, 2013, 10:44:18 PM
Congrats Ray (http://www.freesmileys.org/emoticons/emoticon-games-007.gif) (http://www.freesmileys.org/emoticons.php)  What is the power consumption ? I am thinking of building one but I also want to be able to run on emergency power (generator, battery bank).

Joe
Title: Re: Amplifier for Use With QRP Rigs
Post by: KK0G on May 08, 2013, 11:17:15 PM
Sounds like a nice amp Ray but come on, we need photos! Is there a link to the application notes?
Title: Re: Amplifier for Use With QRP Rigs
Post by: RadioRay on May 09, 2013, 12:26:31 AM
It's showing 140-150 Watts on my MFJ meter, which means that it's somewhere between 1 to 1000 Watts.  Here is a link to the commercial site that sells what you need to build one.  These are not kits, but they are ALL components and the PC board.  The application notes and tech notes are at the bottom of the page.

Also - on my QRZ page, you can just barely see the amp on the top shelf of my radio nook.  I'll post some better pictures in a few days.



>Ray


Ps.  For fun, I hooked up my RockMite QRPp rig and called CQ - had a call come right back from a fellow in southern Germany.  We had a good conversation about how much I miss German bread...  ha ha
Title: Re: Amplifier for Use With QRP Rigs
Post by: KC9TNH on May 09, 2013, 08:32:26 AM
Quote from: RadioRay on May 08, 2013, 09:55:09 PMDue to the small size of my 'shack' all coax goes into a common 'well' in the wall, between the 2x4's to save space.  After making it all neat tidy and segregated, the amp is now able to run at 140-150 Watts for my QRP rig's input of 1-2 Watts.
That is some pretty awesome efficiency. IIRC that's what I heard you running reduced once when on the skeds w/Gil, 40-50w. It was smooth. Nice job with the decorations around the "guest room" cabinet.  8)
Title: Re: Amplifier for Use With QRP Rigs
Post by: KK0G on May 09, 2013, 09:19:17 AM
That's a pretty neat and tidy little shack Ray, much more so than my sprawling junk farm of a shack 8)