[ARC5] IF transformers.

[Kenneth G. Gordon]

On 15 Jun 2013 at 22:55, WA5CAB at cs.com wrote:

> Ken,
> 
> REF NAVAER 08-5Q-4 Figures 37A, 37B & 37C, bottom one third (center
> and top thirds are 239 KC and 85 KC respectively).
> 
> First, my earlier statement about the pie thickness was incorrect. 
> All six 705 KC pies are the same approximate thickness.
> 
> But I'm afraid that some of your statements aren't correct.

I don't doubt that in the least. I was going from memory and I have really bad 
CRS disease for some things. :-)

>  All three
> of the IFT's in the 1.5-3.0 receivers (and for that matter the others)
> use the same base contacts.  1 and 2 Primary, 5 and 6 Secondary.  3
> and 4 are not used in any of the three.  
> 
> Regardless of which pins are omitted from the male connectors in the
> chassis (mainly done in later production SCR-274-N receivers, which
> set does not include a 1.5-3.0 MC receiver), you cannot rotate the IFT
> 180 deg. and plug it in.  The pin pattern is 6-pins on an
> approximately 6-3/4-pin pattern.  The distance from pins 1 to 6 is not
> the same for example as the distance from pins 1 to 3.

Ah HA! Good to know.

> 
> Balance of comments interleaved.


> What I'm building up to asking is this: >
> >If a 3rd IF transformer is fitted into the 1st IFT position, does its
> > >primary > >now get used as the secondary and vice versa? > > Good
> question. I don't think so.
> 
> They do not.  Primary remains primary and secondary remains secondary.

I thought so, but didn't know. Thanks again, Robert.

Thank you for straightening me up,. Robert. 

After this, we should all ask the experts. That's you. :-)

Ken W7EKB