[Collins] 51J-4

[KA9EGW]

Greetings to all!  New guy here; Brian KA9EGW since 1979.  I just acquired a
rather odd 51J4 that has differences [besides the obvious mechanical
filters] from my 51J-3:

1]  The panel, although appearing properly silkscreened, is gloss St. James
Grey, not the usual sort-of-hammertone finish.

2]  No rack handle holes.

3]  Fuseholders [1 marked ‘spare’] in upper left panel corner.

4]  Only 3/16 [approx.] holes for rack mount screws, and only 2 per side.

5]  *No* input/output connections to front panel at all.  No headphone jack,
no RTTY jack, no speaker jack, no DIODE LOAD tip jack
nothing.

6] Serial number is conspicuous by its absence, not stamped on rear panel
like my J3.

7]  AUDIO OUT on rear is a funny little 3-pin job with female pins.

8]  POWER on rear panel is about a 10-pin or thereabouts with male pins.

9]  IF OUT is an RCA connector, riveted.  Looks OEM.

10]  No strain relief on line cord; it exits through about a ¼” hole.

11]  All 4 corners of the front panel are notched about 1/8” [V] x ½” [H].

12]  Lacks MFP stamps.  Lacks MFP yellowing too.

13]  It appears to lack nomenclature-plate mounting holes above the dial
escutcheon, too.

14]  No model # engraved in dial escutcheon either.

The meter movement looks the same as my 51J-3’s.  It has the same tool clips
as my 51J-3.  The PTO s/n appears to be a handwritten “5903 CR”

Please, what have I bought?

73, Brian KA9EGW