The external speaker swtich is the first thing I wiggled. The sams I have for thim one is for the correct sound module. This is the 10 watt analog board. I have 4.89vdc on pin 27 of U3101 whether the speakers are turned on or off in the menu. 4.9 is what is called for on the schematic also. thanks Walter --- Joe Dickerson <[EMAIL PROTECTED]> wrote:
> Walter, > What voltage do you have on pin 27 of U3101 > (speakers off)? It should > be .02 on and 2.29 off. Also, check the external > speaker switch to see > if it has gotten "dusty" over time. It seems > there was also a muting > transistor that was a culprit on this chassis, > but I can't remember > which one. > Good luck, > Joe > > walter wood wrote: > >>Recap" > >>This set has a great picture, but the sound > would > >>go off in about 5 seconds. > >>List members were generous in providing > >>schematics. > >>One tech suggested opening up the DC sense line > >>to > >>see if that was the problem. > >>I unsoldered pin 16 of JS1900. > >>The audio stays on longer now, but still shuts > >>off. > >>There is a slight thump in the speakers at turn > >>on, > >>but nothing unusual at all when the sound > >>disappears. > >>I got out my trusty Radio Shack audio signal > >>tracer > >>and I have sound on pin 7 of U1901 and U1902 at > >>all > >>times. > >>This can be varied with the sets volume control > >>as > >>it should. > >>Pins 2 and 4 have the required +17 and -17. > >>Pin 3 shows -12.3 on the schematic. > >>there is -17 there at plug in. > >>That goes to -13 when sound is present, then > goes > >>to app. -15 when the sound disappers. > >>The afore mentioned pin 16 JS1900 is still > >>unsoldered. > >>This might be a clue. > >>When I was testing the voltages the probe > slopped > >>and I temporally shorted Pin 5 to 3 on U1901, > and > >>the sound returned briefly. > >>I have to admit that I don't understand this > >>mute/DC sense circuit. > >>Anyone got any clues at this point? > >>TIA > >>Walter > > > > > > > > ===== > > Walter Wood > > Future Tech Home Center > > 2786 Hwy. 43 N. > > Lawrenceburg Tn. 38464 > > 931-829-3337 > > Fax 931-829-4044 > > mailto:[EMAIL PROTECTED] > > > > _______________________________________________ > > Tech Repair CD...order your just $49.00 plus > shipping...One year of updates free. > > www.intrepid-video.com www.tech-repair.net > > Techs mailing list > > [EMAIL PROTECTED] > > > http://intrepid-video.com/mailman/listinfo/techs_intrepid-video.com > > > > > -- > Joe Dickerson > Joe's TV & Appliance > Rt 1 Box 3781 > Jasper, Texas 75951 > (409) 384-3325 > use same no. for fax > > > _______________________________________________ > Tech Repair CD...order your just $49.00 plus > shipping...One year of updates free. > www.intrepid-video.com www.tech-repair.net > Techs mailing list > [EMAIL PROTECTED] > http://intrepid-video.com/mailman/listinfo/techs_intrepid-video.com > ===== Walter Wood Future Tech Home Center 2786 Hwy. 43 N. Lawrenceburg Tn. 38464 931-829-3337 Fax 931-829-4044 mailto:[EMAIL PROTECTED] _______________________________________________ Tech Repair CD...order your just $49.00 plus shipping...One year of updates free. www.intrepid-video.com www.tech-repair.net Techs mailing list [EMAIL PROTECTED] http://intrepid-video.com/mailman/listinfo/techs_intrepid-video.com
