Larry, You probably have some slivers of aluminum embedded in the thermal pads. Unless you have some good thermal conductive material laying around, I would request replacement thermal pads from [email protected].
BTW - when you replace the hardware, do not use the internal toothed lockwashers - they can dig out bits of aluminum and cause just the problem you are having. Substitute split lockwashers. You may have enough left over from the option installation, normally a few extras are included. 73, Don W3FPR On 1/23/2011 8:43 PM, L Kendall wrote: > I built the KNB2 board and installed it today. > > No problems with that, but it occurred to me while the 100 Watt board > was removed to check the TO220 packaged Q7 and Q8 on the RF board for > any electrical continuity to the heat sink . > > I have to back those 4-40 nuts out to barely finger tight or it measures > short to ground. > > Is there a suitable substitute material I can use for those adhesive > insulating pads between the transistor and the grounded heat sink? > Elecraft p/n in the manual is E700002. > > Thanks, > Larry > K5END > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
