[MRCA] [BoatAnchors] Smart People: BC-9 TX/RX Freq Shift- Q?

[Katsuhiko Hirai]

Dear Dave, AB5S

  Good morning.
I appreciated your kind note.
I found one example of the audio frequency transformer into the article 
as follows:

Issue: AUG 1925 - QST (PG. 16)
Title: The DeForest D-17 Receiver   which includes two A.F.T. 
Author: Livingstone, Edward A.
Article: QST Archive [PDF]

Copied sentences:
" First A.F. Transformer--(11)-- Ratio;5:1. DeForest type A-50. Turns: 
 Primary 2800 of No.38 wire. Secondary 14,000 of No.40 wire. D.C. Resistance: 
 Primary 540 ohms; secondary 7370 ohms. Impedance: Primary 60,000 ohms; second-
 ary 1,500,000 ohms. Inductance at 1000 cycles: Primary 9 henries; secondary 
 250 henries.
  Second A.F. Transformer--(12)-- Ratio: 3.5:1. De Forest type A-35. Turns: Pri-
 mary 2800 of No.38 wire. Secondary 9800 No. 40 wire. D.C. Resistance: Primary 
 540 ohms; secondary 5160 ohms. Impedance: Primary 55,000 ohms. secondary 
 680,000 ohms. Inductance at 1000 cycles: Primary 8.5 henries; secondary 102 
 henries. In both cases the closed core is of laminated silicon transformer 
 steel 5/8 inch square and is sufficiently large to permit maximum amplifica-
 tion without distortion over all frequencies. "

I'm happy if these notes were helpful for you, although you might know it well.

Have a nice new day for you,
Best regards,
Katsuhiko Hirai, JA3ECA


On Wed, 8 Feb 2017 06:28:04 -0600
"David Stinson" <arc5 at ix.netcom.com> san wrote:

> P.S.  I'm sorry, I do not know the turns ratio of the interstage transformers.  Perhaps members who are more familiar with these very early audio amplifiers will have some insight.
> 73 Dave S.

-- 
平井勝彦 <mxc04040 at nifty.ne.jp>