[Collins] 51J-5

[Chris Kepus]

For those of you who might be interested in the 51J-5.

 

 I sent a request to the Hammond Museum of Radio for info on the 51J-5 that
they acquired.   Larry Asp, a museum volunteer, was kind enough to respond
and also sent me three pictures.  However, they are not quite as nice as the
three pictures of the 51J-5 on the Collins Radio Association site here:
http://www.collinsra.com/cra_album/0009/cra_0009.html.  

 

Here are Larry's comments:

 

"Chris - I volunteer at the museum - here are photos of the 51J5. There may
be only 2 in existence - I found out some information on one of them, we
have #2, havnt found out the fate (if any) of the 3rd." 

 

".. we have not turned it on yet. However it was in regular use by its
former owner, and was aligned as little as 4 yrs ago, and was in working
orderl  Since it is a prototype,  not all the bugs were worked out of it.
The passband tuning works on only odd bands properly, realingning it
differently, the pass band works only on even bands properly. Since the 51S1
(newer technology) went into production instead, thats the way it was left.
This radio was made in Canada in Collins Toronto plant where the last 75A4s
were made. They were preparing a new model general coverage reciever. So -
it has a 51J4 tuning and IF arrangment, and a 75A4 passband tuning,
mechanical filters, and SSB detector. It is likely the mechanical filters
are prototypes since the 51J4s use 500kc (I dont know how they modified the
filters), and it is in a 75A4 case. We have no papers or diagrams of the
radio, and it is not mentioned in any Collins books I have come accross.
There is a write up done for the CCA about 10 yrs ago on the radio written
by Peter Lower. For the moment it is on display beside a 75A4 in the
museum's Collins collection. Picture(s) will go into the museums web site
soon, and hopefully it will generate some interest and turn up more
provenance for the piece. We would love to get hold of a diagram. We don't
plan any full exams yet. We understand that another one of these turned up
at Dayton several yrs ago for 2 or 3 yrs running - we dont know where it
went. The museum is happy to have the piece so it can be appreciated by
anyone who has an interest in Collins." 

 

 

73,

Chris

W7JPG