Back around Christmas I took a chance on a "for parts or repair" function generator on Ebay. When it arrived, I noticed a rattle, so I disassembled it before testing. A 5w resistor had gotten so hot, it fell off the board (see my Toasty resitor thread"
I replaced it, and did a quick test. Horrid looking waveform, and that resistor and a transistor close to it were very hot.
Some testing found that Q522 (a 2N2905a) was shorted, and it's neighbor Q520 (2N2219A) was also bad.
Digikey and Mouser were both back-ordered on one of the transistors so I ordered from Jameco. $6.00 shipping and it took about 3 weeks.
They arrived just as we were leaving for Mexico, so I just got around to replacing them today. Replaced the 2 transistors, and the 2 toasty looking resistors, and fired it up. Works great!
Transistors and resistors are running cool, and waveforms look great!
I replaced it, and did a quick test. Horrid looking waveform, and that resistor and a transistor close to it were very hot.
Some testing found that Q522 (a 2N2905a) was shorted, and it's neighbor Q520 (2N2219A) was also bad.
Digikey and Mouser were both back-ordered on one of the transistors so I ordered from Jameco. $6.00 shipping and it took about 3 weeks.
They arrived just as we were leaving for Mexico, so I just got around to replacing them today. Replaced the 2 transistors, and the 2 toasty looking resistors, and fired it up. Works great!
Transistors and resistors are running cool, and waveforms look great!
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