Hello friends, I built a kit K1 80/40. Everything was no problem. All values of resistors and DC voltages were OK. But in chapter 9, part "Band 1 Allignment", transistor Q7 has been melted (2W at 80 m band). I changed it and after that I measured current - 0.1 W on 3.6 MHz current is 1.1A! On 7 MHz, is slightly better - 0.1W is 0.4 A but the 2W is 1.3 A. After several attempts to find mistake, I tried to use the "Signal Transmitter tracing" with DRV-ground jumper. Instead of RF Probe I used the old oscilloscop in multimetr mode. I performed the measurements to the point 15. All values looked like okay, but from the point 10, I watched the unstability. I switched oscilloscop to the measurement curve mode. And on OSC it is not pure sine wave. The point of MIX has been very vibrant. ATTN is clean. I do not know if the problem is on 6-7 intputs U8 or output 4. Please, see videos of measuring on youtube. ociloscop 150ns time raster: http://www.youtube.com/watch?v=fYTOw9DWfKI ociloscop 50ns time raster: http://www.youtube.com/watch?v=9mUunLQdBuU ociloscop-multimeter: http://www.youtube.com/watch?v=oFaKCssXsA In every video first part is on ATTN, second on OSC, and the third on MIX.
Please, do you have some recommendations how or where to find the error? Can Xtal X6 defective? Thanks 73 Igor OK1TGI ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
