[hpsdr] K5OOR SDR "Preamp"

[Daniel Quigley]

Folks,
 
I ordered, received and built one of K5OOR's "SDR Preamps"  (Model PA-100) which will act as a 5-8W driver stage to my 100W SB-104a brick amp I intend to use with Penny.  O was asked to report back on my experience with that product. 
 
General:
The kit I received contained all parts, the PCB was good quality and the instructions were sufficient to complete the assembly and bias the amp.
 
Details:
I completed kit assembly in about 5 hours.  I rate the level of difficulty as intermediate.  The most difficult steps in the assembly were winding the transformers and coils - but the instructions for winding those were better than I have seen in other kits.  Beyond that it is pretty much plug, solder and pray.  :)  
 
The only "MacGyver work" was (oddly enough) adding the snubber diode for the T/R relay to the board. The diameter of the leads for the supplied part (a 1N4004) were larger than the through-plated component holes.  I had to use remnant leads from other parts to complete that step.
 
After the assembly, I was able to bais the amp (following written instructions that could be clarified a bit).  The quiescent current was lower than what was noted in the docs, but the amp "biased" pretty much as decribed.  
 
By the weekend I should have this driver amp integrated and will post another report.  I was VERY interested in the post about poor audio using this amp as audio is inportant to me.
 
Questions, flames, comments?
 
73's
Dan (N7HQ)
 
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