Yes, I would definetely use a sony original part #. Shannen's Electronics 1619 N Taylor Ave. Garden City, KS 67846 (620) 275-4660 (620) 275-4668 (fax) shannen@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx -----Original Message----- From: techassist-bounce@xxxxxxxxxxxxx [mailto:techassist-bounce@xxxxxxxxxxxxx]On Behalf Of HarrisTV50010@xxxxxxx Sent: Saturday, May 31, 2003 4:44 PM To: techassist@xxxxxxxxxxxxx Subject: [TechAssist] Sony CTV KV27EXR20 (Chassis ANU-2) H. O. T. Shorts after 20 Minutes. I have a Sony Model KV27EXR20 Chassis ANU-2. The first time this set was in the shop it had a bad STRS6301 Regulator IC but the H. O. T. Was Ok. I checked and resoldered any questionable connections. The customer had the unit home about 2-weeks and it died again. This time the 2SD1886 H. O. T. had shorted. I checked the horizontal circuit using our Sencore TVA62 and everything checked ok. I replaced the H. O. T. and it ran for 20 minutes and shorted again. This time I thoroughly rechecked the regulator circuit using a resistor load and everything checked perfectly. I thoroughly went over the chassis for any questionable connections. I resoldered everything is the base drive & collector circuits of the H. O. T. I replaced the 2SD1886 again. I monitored the base drive and the collector waveform using our X100 scope probe. Everything looked textbook perfect. The Collector pulse width was 14us, which is normal. I did start monitoring the temperature of the H. O. T. Using an Infrared Thermometer. The temperature started rising and the transistor shorted at about 165 degrees. Does anyone have any ideas what might be causing problems? I am using RCA SK 2SD1886 which I haven't had any problems in the past. I checked RepairWorld and someone had used a 2SC4729 as a replacement. Do I need to try an exact Sony replacement? Any thought would be greatly appreciated. TIA, Dale Dale A. Lubow... HarrisTV50010@xxxxxxx ..515-232-1109..(Fax)515-232-3356 Harris TV & Appliance..........335 Lincoln Way.....Ames.....Iowa.....50010-3384 **************************************************************************** * The Tech Address Book: http://www.tech-assist.org/secure/tip/contact.html Add a Repair Tip Here, or Change/Remove your Email Address: http://www.tech-assist.org/secure/tip/main.html Lost Password: http://www.tech-assist.org and select "Lost your Login Info?". Email Archives: http://www.freelists.org/archives/techassist/ ***************************************************************************** The Tech Address Book: http://www.tech-assist.org/secure/tip/contact.html Add a Repair Tip Here, or Change/Remove your Email Address: http://www.tech-assist.org/secure/tip/main.html Lost Password: http://www.tech-assist.org and select "Lost your Login Info?". Email Archives: http://www.freelists.org/archives/techassist/