Hi: The Tek 2430A input is "50 Ohm 5V RMS". I put 200V in CH1, then smell something. after that the 2430A can't pass the Extended-Diagnostics! (CH2 is OK). Does anyone know which component was burnt away? thanks Li 0000 Extended -Diagnostics 1000 Sys-Rom Pass 2000 Reg Pass 3000 Sys-Ram Pass 4000 FPP Pass 5000 WP Pass 6000 Cksum-Nvram Pass 7000 CCD Pass 8000 PA Fail 8100 Offset Fail 8110 Norm-SP Fail 8111 CH1 Fail 8112 CH2 Pass 8120 Norm-FISO Fail 8121 CH1 Fail 8122 CH2 Pass 8130 ENV-SP-slow Fail 8131 CH1 Fail 8132 CH2 Pass 8140 ENV-FISO-slow 8141 CH1 Fail 8142 CH2 Pass 8200 Pos-Agin Fail 8210 CH1 Fail 8220 CH2 Pass 8300 Balance Fail 8310 50mV Fail 8311 CH1 Fail 8312 CH2 Pass 8320 20mV Fail 8321 CH1 Fail 8322 CH2 Pass 8330 10mV Fail 8331 CH1 Fail 8332 CH2 Pass 8340 5mV Fail 8341 CH1 Fail 8342 CH2 Pass 8350 2mV Fail 8351 CH1 Fail 8352 CH2 Pass 8400 Gain Fail 8410 50mV Fail 8411 CH1 Fail 8412 CH2 Pass 8420 20mV Fail 8421 CH1 Fail 8422 CH2 Pass 8430 10mV Fail 8431 CH1 Fail 8432 CH2 Pass 8440 5mV Fail 8441 CH1 Fail 8442 CH2 Pass 8450 2mV Fail 8451 CH1 Fail 8452 CH2 Pass 8500 INV-Gain Fail 8510 50mV Fail 8511 CH1 Fail 8512 CH2 Pass 8520 20mV Fail 8521 CH1 Fail 8522 CH2 Pass 8530 10mV Fail 8531 CH1 Fail 8532 CH2 Pass 8540 5mV Fail 8541 CH1 Fail 8542 CH2 Pass 8550 2mV Fail 8551 CH1 Fail 8552 CH2 Pass 8600 Var-Max Fail 8610 CH1 Fail 7620 CH2 Pass 8700 Attenuator * Pass 9000 Trigs Fail 9100 Offset Fail 9110 A-trig Fail 9111 CH1 Fail 9112 CH2 Pass 9113 Slop Fail 9114 Ext1X1* Pass 9115 Ext1X5* Pass 9116 Ext2X1* Pass 9117 Ext2X5* Pass 9120 B-trig Fail 9121 CH1 Fail 9122 CH2 Pass 9123 Slop Fail 9124 Ext1X1* Pass 9125 Ext1X5* Pass 9126 Ext2X1* Pass 9127 Ext2X5* Pass 9200 Gain Fail 9210 A-trig Fail 9211 CH1 Fail 9212 CH2 Pass 9213 Ext1X1* Pass 9214 Ext1X5* Pass 9215 Ext2X1* Pass 9216 Ext2X5* Pass 9220 B-trig Fail 9221 CH1 Fail 9222 CH2 Pass 9223 Ext1X1* Pass 9224 Ext1X5* Pass 9225 Ext2X1* Pass 9226 Ext2X5* Pass 9300 Repet* Pass