Hi Mike,
That mod should apply to all of the 51J series receivers. I know
for sure that it is on the J3 and J4, and on the R-388 version of the J3.

Pete

"Mike Knudsen" wrote in message
...
In article ,
"Pete
KE9OA" writes:

No, it did not have a product detector. I did do one author's mod to
these
receivers over the years, where you convert the cathode follower for the
I.F. output to a product detector. It was great, because the mode switch
on
the front panel has an extra set of contacts that you can use for routing
the audio.

Would that mod also apply to the J3/R388? The need for extra audio
switching
is a big problem in most PD mods, leading to use of relays in R390A for
example, with all kinds of problems. Don't recall seeing extra switch
contacts
on my 388, maybe just on the J4.

Since the BFO switch is broken on my SP-600, I just might replace it with
a
3PST switch (good luck) and put a PD tube in place of the BFO
riveer. --Mike
K.

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