03-26-2016, 08:32 PM
Well, it's fixed - and a real DUH! moment for me.
I traced the loss of signal to Q3 on the head amp (phono preamp) board (see schematic below).
Then I took a close look...
...and saw that, yes. I had installed Q3 backwards (collector and emitter switched).
Like I said, DUH...
Removed Q3, tested it and (amazingly) it was still good. Reinstalled, making sure the leads were in the proper positions this time.
Worked like a charm...
[Image: http://www.philcoradio.com/images/phorum...1-001a.jpg]
The SX-1500TD is back in my home office now. I'm listening to the smooth tones of Nat King Cole playing on my Technics turntable as I type.
And even though the record (Love is the Thing, 1957) is in mono, the music is coming through both channels...nice and clear...sounds great.
So now, that is it for this SX-1500TD thread.
I traced the loss of signal to Q3 on the head amp (phono preamp) board (see schematic below).
Then I took a close look...
...and saw that, yes. I had installed Q3 backwards (collector and emitter switched).
Like I said, DUH...
Removed Q3, tested it and (amazingly) it was still good. Reinstalled, making sure the leads were in the proper positions this time.
Worked like a charm...
[Image: http://www.philcoradio.com/images/phorum...1-001a.jpg]
The SX-1500TD is back in my home office now. I'm listening to the smooth tones of Nat King Cole playing on my Technics turntable as I type.
And even though the record (Love is the Thing, 1957) is in mono, the music is coming through both channels...nice and clear...sounds great.So now, that is it for this SX-1500TD thread.
--
Ron Ramirez
Ferdinand IN
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
