[R-390] Differences in 390A IF decks

[Tom Norris]

Tim, you know that, and I know that. I had posted the links for the  
benefit of those that didn't or for those that collect photos for no  
good reason. Or for good reason, either one. I think there is at  
least one, who I forget, that likes new and different pix taken.

On Aug 15, 2005, at 4:43 AM, Tim Shoppa wrote:
>
[snip]
> I assume you're talking about the fixed rather than variable caps
> around the filters?
>
yup, and the fact it's a Collins [Blessed be Art, etc] AFAIR all the
Motorola and Collins decks pre 1954 had fixed caps. I suppose most
Mot/Col decks out there will be capless, since they weren't made
past '56. An odd thing about the deck in the photo - there is no
contract number marked anywhere on the thing. Just a Collins p/n and
a serial. The other Collins 390A's I've had had the contract numbers,
at least I think so. I may have been hallucinating at the time, though.
heehee

Tom M reminded me of the different sheet metal design and other things
that were used in later contracts by EAC. I may also do comparison pix
showing those as well, I probably have an extra EAC module around here
somewhere. (rummage rummage)

Tim asks: "What exactly is that doo-dad in the ballast tube socket?"

The doo-dad?  It's a "Modified Horizontal Low Resistance Current Pass
Device"  Which means I have a 9-pin shorting plug underneath instead of
a b*11*st. The tube shield and label are there for effect, since the  
radio
is going out the door to someone with an odd sense of humor. I used
12BA6's for PTO and BFO. The radio is an Amelco, but it's a mutt. While
it has an Amelco RF deck and P/S, the IF is Collins and the audio is
Stewart-Warner. Now if the p/s were Helena-Rubenstein, we'd be
all set.... hehe

73

Tom NU4G