[HBR] Help with old home-brew receiver

[hbr@mailman.qth.net]

Well ... We may have a winner.   QST, March, 1956, p. 39, "A Nine 
Tube Amateur Band Receiver With 3-Kc. Selectivity", by Emory E. 
Toops, Jr., W9HLH.   This is a double conversion receiver with the 
tubes as listed by Kevin except that there's a 6BA6, there's no 
6BY6, and there's no 12AU7.

The tube lineup in the W9HLH receiver is:

6AQ5 Audio Output
12AX7 1st Audio/BFO
6AL5 Detector/AVC/ANL
6BJ6 x2  85 Kcs IF's
6BE6 x2 1st & 2nd mixer
6BA6 RF
6C4 Local Osc.

The 1st IF freq. is 1600 kcs and consists of just one transformer 
located between the two mixer stages.   The 6BE6 2nd mixer is self-
excited, with a crystal at 1685 kcs.   

That looks like it, though there are obvious questions about the 
12AU7 and 6BY6.   The 6BY6 is probably a substitute for a 6BE6 -- 
the basing is the same.   I'd guess the unidentified tube is the 6BA6 
RF stage -- if so it will be nested in with the coils.   The 12AU7 ... Q-
multiplier?    Selecto-ject?   The TNS (twin noise squelch) used a 
12AX7 I think?   

The author describes his goal as coverage of 80 through 10 meters, 
simple to construct, and use as many parts as possible from a BC-
453.   He describes use of the IFTs, BFO coil, nine bypass caps 
(ugh ...) and resistor terminal boards from the command set.

"No S-meter was included because it was considered an 
unnecessary expense."   The receiver is tuned with a National UM-15 
three gang 15 mmf/section variable cap.

Congratulations, Kevin -- you snagged a *rare* one!   And that's a 
good sound design;  it should be quite usable on the lower bands in 
any case and on 20 and up according to the builder's degree of 
fanaticism.   

Unfortunately I have no blowback facilities for microfiche but maybe 
someone can go to a CDROM version and print the article for you.   
It's a pretty good article, too.

Walt Hutchens
KJ4KV