[Drake] TR-7 Receiver Noise Question

Sun, 28 Mar 2004 13:54:54 -0500

Thanx to all who took the time to respond to my inquiry.  I received as many
different ideas as there are people who responded, so there appears to be no
single, common cause for my problem.  No biggie, I'll find it when I have
the time to dig into it.  While I'm in there I'll clean and reseat the board
contacts, as that reportedly cures many ills.  Regarding the 10 volt pot,
I'm not going to touch it unless I'm prepared to do the alignment: even if I
don't turn it, a noisy or dirty pot can change adjustment with any sort of
disturbance and I don't want to touch it until I have the time to go all the
way, if necessary.

73,
Jim

-----Original Message-----
From: Larry Taft [mailto:[email protected]]
Sent: Sunday, March 28, 2004 8:44 AM
To: [email protected]
Cc: [email protected]
Subject: Re: [Drake] TR-7 Receiver Noise Question

Jim,
A possible source of the noise is the 10 volt adjustment pot on the power
supply board.  Pull the top cover of the TR-7 and lightly tap on the
right-most pot on the PS board located on the right side just behind the
front panel.  Do NOT give it a twist as that will then introduce you to the
alignment process for the rig.
73,  Larry  K2LT
drakerepair.com
800-687-9161

At 07:26 AM 3/28/2004 -0500, you wrote:

>Hi All:
>
>My TR-7 exhibits a low level background noise that sounds similar to random
>atmospheric static.  The noise comes from inside the radio.  It's audible
>when a dummy load is connected, the RF gain is turned down and there's no
>external noise to mask it.  It's most noticeable (to the point of being
>extremely annoying) when using the 500 Hz CW filter; it's also present when
>using the other filters, but it's almost inaudible and isn't a problem with
>other modes.  It's independent of the audio gain control, so that's a clue
>as to where to start looking for the noise source.  Before I dig in, has
>anyone heard of this before?
>
>Thanx & 73,
>Jim
>WA2MER
>
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