[Boatanchors] 51J's vs R-338's?

[Garey Barrell]

Robert -

The 51J-4 has BOTH the crystal filter and the mechanical filters. 

There is an R-388A/URR, plus there was a "kit" offered by Collins to 
convert the R-388 to an "/A", consisting of the subchassis with two 
tubes, the switch  and filters.  It was called the "Mechanical Filter 
Conversion Kit.   354A-1, p/n 522 9040 002.    I think (?) the same kit 
could be installed in the 51J-3, but not certain.

There are other minor differences, but the mechanical filters are 95% of 
the difference.

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual
<http://www.k4oah.com>



WA5CAB at cs.com wrote:

>Eugene,
>
>The 51J-4 has, as someone else has already pointed out, mechanical filters 
>instead of (?) a crystal filter in the front of the IF strip.  There was/is 
>supposed to be an R-388A/URR equivalent to the 51J-4 but I've never seen one.  
>Seems like someone either here or over on the Milsurplus or original Boatanchors 
>lists reported having one or having seen one.  But I may have dreamed that.
>  
>
>  
>