[Milsurplus] BC-9: Earlier and Later Operating Instructions.

[Kenneth G. Gordon]

On 13 Feb 2017 at 0:00, Mike Morrow wrote:

> Ken wrote:
> 
> > From the similarity of the circuit AFTER the oscillator tube,
> > I suspect that the two transformers, T-2 and T-3 are simply
> > common 3:1 transformers.
> 
> Ken, there is no T3 in the BC-9-A.  There are two T-1 and one T-2 AF
> transformers.  In the BC-9-* schematic, all identical components got
> the same designation...hence two T-1s, two R-2s, and two R-3s. 
> 
> T-1:  Signal Corps Coil C-21, 1:4 (plate:grid) turns ratio.
> T-2:  Signal Corps Coil C-57, 1:1 (plate:hi-z headphone) turns ratio.

Ha ha, Michael, you are such a kick! :-)

Your accuracy is amazing.

If I had said something like, "Looking at the schematic which W6MAB so kindly drew for us, 
the first transformer on the left is obviously a 1:1 type since, as far as I can see, that is the 
only one whose ratio is listed in the bit of information that David so far as been able to give 
us. In my opinion, from the similarity of the circuit to others with which I am familiar, the 
other two transformers, that is the second and third ones from the left are most likely 
standard 3:1 transformers."

That would have been more clear to you, I'll bet.

Instead, I had "named" them T-1, T-2, and T-3 as one would normally do when drawing 
them on a schematic to indicate that T-1 was the first one on the left, T-2 was the second 
one from the left and T-3 was the third one from the left.

I looked around on the net to see if I could find the actual turns ratio of the two "T-1s" but 
could find nothing, so I am very grateful to you that you found the ratios to actually be 4:1.

Thank you.

Ken W7EKB

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus