[HBR] Rookie here

[Walter A. Hutchens]

Steve said:
> I'm like to homebrew one heck of a good receiver...and would appreciate
> your generous help in the matter.

This is what I've wanted to do all my life -- I mean, since about 16 y.o.   
Unfortunately it took 50-some years for my design and construction skills to 
get to where I could hb ANY receiver and get it to work.   And I still have 
two or three good unfinished (not quite working) projects sitting around for 
the day when my skills catch up with the challenges I dreamed up.

Thus, I'd suggest starting with something not above three tubes unless you 
already have some vacuum tube construction experience.    There's just so 
darn much art to learn and it can only be learned by doing.   

When you have *A* project that works, you'll know what you're ready to do 
next and have some idea which way you want to twist the trade-offs that 
N2EY mentioned.    If you are feeling fairly comfortable I don't think you 
could do better than something like the HBR-8.    With plug-in coils you can 
get whatever tuning ranges you like, by winding appropriate coil sets.   

I think I'd start with the receiver theory in the Radio Amateurs Handbooks 
of the mid-late 60's.   There are also some fine project receivers there.  
The RSGB handbooks Jim mentioned are also excellent on theory.   Beyond 
that I suggest G2DAF's extended discussion of receiver design principles; I 
believe that that was added to the HBR CD available from our listowner.

The conclusions in G2DAF's paper are somewhat dated, but the issues and 
the way you think about them in a design, are timeless.

Current project is a substantial complexification of the Handbook 2X4.   7 
tubes: 35W4 rectifier, 12AT7 push-pull mixer, 12AU7 push-pull oscillator, 
2x 19JN8 IF, 1/2 19JN8 (triode, diode connected) bias rectifier, 1/2 
19JN8 (triode) AGC detector, 1/2 12AU7 plate detector, 19JN8 1st audio 
stage, 1/2 12AU7 2nd audio, 1/2 19JN8 (triode) xtal BFO.   IF is 5400, LO 
tunes 1400-1900 giving coverage 3500-4000 and 6800-7300.  Half lattice 
crystal filter.  

This one works well but 'transformerless' design of a high gain selective HF 
superhet is not for the faint of heart because of the decoupling issues 
associated with having two separate grounds that have a voltage between 
them.

Walt
KJ4KV