[Collins] Question about a 70E-11 PTO

[Heinz und Hannelore Breuer]

Hi,

a fellow ham without access to the list has a question quoted below
about a 70E-11 PTO.
If you can help him please reply to <reformschool@juno.com>

Thanks and 73
Heinz DH2FA, KM5VT

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Recently picked up a Collins PTO for either use as a 
replacement for my eldico pto or a stand-in external vfo to serve
while the stock pto is being rebuilt.  We both mused over just
which receiver it came from, and what in input voltages and 
where the output connects are.  When i got home and began
acutally looking into it, the PTO seems to be unexpectedly different
from the PTOs i have worked with in my murky past.  So i went
on line.

Tried to google up some info on it, but came only to dead ends 
for my model which is a 70E-11.

This particular PTO has been adapted for use with an HRO dial,
the PW yoke and harness being braced to the PTO using the 3
front frame bolts.  I had to logic it out, it looks so like a factory job
machine wise.  But you can recognise the PW cam and dial shaft 
immediately.  Collins and National?? Nahh, it's a homebrew.

I did find a reference showing the voltages and the freq. range.
But the reference seemed incomplete in that while it indicated a
B+ voltage needed at 250v, it did not indicate a tube compliment.
And,-- unless inside this what appears to be a hermetically sealed,
non vented squarish sub-assembly canistre,--  there is no indication
that there is any tube life even present in or on this thing. Not even
a place for it.  Does the can just contain the coil and slug mechanics?
But then why are there 4 inputs, 2 of them with polarity marks?

According to a hand scribed lable affixed to it, this PTO has been set 
for 2500 kc to 3000 kc. so it was used most likely in another homebrew 
setup, like a vfo or another receiver.

Anyway, i need a schematic and perhaps a bit of narrative on
this thing.  For one thing, unlike my eldico pto, it does not have
any tubes or trim pots on the housing, save one.. The Eldico has
a 6U8A and two trim pots on the top removable cover.  This
one **looks** hermetically sealed, with 4 inputs marked by the
owner : (1), (+), (-),and (no mark).  There is a round port covering
held by 4 screws, the removal of which reveals the back of a 
printed circuit board.  So i conclude that it must be solid state?
Or did Collins place the actual active circuitry, the tubes, etc.,
outboard ( which doesn't seem to make good sense from a
mechanical stability and rf shielding standpoint.)?  Or is it 
actually sealed up in this box?

There is another alphanumeric indicator on the square pto
housing, "P-3102". 

One thing is sure, it is smoooooth!  And solid as Gibraltar.
10 turns, perfect for the HRO dial.  Bry, i think i'm gonna have
fun with it soon as we nail down the operation.

( a picture of it appears on his web site.)

I would like to get this thing going, either in the eldico, or in a
nice homebrew receiver.  Any info would be appreciated.
I have never even brushed shoulders with Collins stuff before,
aside from Eldico, this is my only collins piece of equipment.

-gary // wd4nka
( ReformSchool Music)