Mike, I¡¯d look around that area for a shorted capacitor. I had some smoke a few years ago that was caused by a shorted SM cap. It should be fairly easy to find.?
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
On Thu, May 1, 2025 at 20:30, Mike W5RKL via groups.io <
mikew5rkl@...> wrote:
I'm working on bringing a Drake TR3 back to life. During power up
I noticed smoke coming from below the chassis. I quickly powered
the TR3 off.
I turned the TR3 upside down, front panel facing me, and found a
1/2W resistor that had overheated. The picture below shows the
location of this resistor. Does anyone know the resistor's value
and where on the schematic it's located? The Yellow shaft is
used as a pointer and the Black arrow is also pointing to the
resistor. It's to the "Left" of the audio transformer and between
the 2 small PC boards.
I need to determine what that resistor is so I can find it on the
TR3 schematic then track down what caused it to over heat.
The TR3 was in "receive" when the resistor overheated. There
was no audio heard in the speaker. The 8 pin remote VFO plug
was in place with pin 2 connected to pin 8 as shown on the
TR3 schematic (the RV3 was not plugged into the remote VFO socket).
Any help would be appreciated. Please reply direct to my email
address.
73
Mike W5RKL
