[R-390] That's more like it!!!

[g4gjl]

I cannot answer your first question as I (sadly) have no T-368 experience!
Any one wishing to rectify this situation by donating a T-368 to me is most
welcome!!

However, the mod antenna relay you described is part official and part
homebrew, it seems to me.

True, there will be an impedance mismatch at the 50 -ohm SO-239, but in
reality this is of little significance to most people.

The relay unit might be one from another similar application in another type
of receiver else has been locally modified.
I think some of the R-390 (no A) relays use removable coax connectors. All
the 390-A versions I have seen have the body of the relay assembly and the
coax connectors and an integral casting.

The electrical mod of grounding one side of the RF input transformer was
first specified by the Navy, as one of their numbered modifications. A web
search will most probably uncover a copy of the official document.

Pete
G4GJL

----- Original Message -----
From: "K3PID" <k3pid@comcast.net>
To: <R-390@mailman.qth.net>
Sent: Monday, January 26, 2004 12:42 AM
Subject: [R-390] That's more like it!!!


> Well I guess I am getting through...:>). Anyway the two questions were as
> follows:
>
> First. ( I now realize that this may not have come across as a question. I
> was looking for confirmation of my assumptions)
>
> SIDETONE QUESTION 1/3/2004
>
> The sidetone output of the T-368 is taken through a cap from the wiper of
> the 500 Ohm cathode resistor of the cathode follower. Is it normally
> connected across the "output" side of the 600 Ohm audio output of the
R-390?
> If so then the level of the sidetone is controlled by the cathode resistor
> independ from the R-390?
>
>
> Second.
>
> ANTENNA INPUT MODIFICATIONS 1/23/2004
>
> On my R-390 someone removed the twinaxial socket on the balanced input and
> replaced it with an SO-239. The center conductor of the new connector
passes
> thru to the high side of the transformer while the other side is now
> grounded. Was this a common mod? why wouldn't you just replace the
connector
> on the unbalanced input with the SO-239?
>
>
> Thanks and sorry if I shouted!! In the past I've gotten great answers from
> the group but it seemed like no one was listening... You know how it is
when
> you have the rig open on the bench and you're waiting for info...
>
> K3PID
>
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