+++++++++++++++++++ From: "Larry - WA2DGD" To: , Subject: Re: [Elecraft] Radio Resets By Itself Date: Fri, 2 May 2003 10:52:01 -0400 Excellent point Ron. When I read the message regarding BFO drift, it sounded like you should "key down" for about 10 minutes to "heat up" the interior of the K2, something I did not feel comfortable doing. Sending CW for 10 minutes is far more acceptable. Thanks, Larry WA2DGD ----- Original Message ----- From: "Ron D'Eau Claire" To: Sent: Friday, May 02, 2003 10:41 AM Subject: RE: [Elecraft] Radio Resets By Itself There's a resettable fuse in the K2. It sounds like that is tripping and shutting down the K2. If you are trying to run the K2 at 100% duty cycle, the finals may be drawing enough current as they heat up to trip it, then it resets once things cool down. When you say "transmitting" into a dummy load, what are you transmitting, Jason? Are you sending normal CW or are simply holding the key down (uninterrupted carrier)? The K2 is not rated for 10 watts output with the key down (that is, 100% duty cycle). I ran a number of tests of the stability transmitting into a dummy load, but always sent CW. I loaded up a message buffer and set it in "repeat" mode most of the time. It seemed to work as well to send dits or dahs (although the latter has a much higher duty cycle). Ron AC7AC K2 # 1289 -----Original Message----- Last night I was trying the frequency stability test as outlined in the K2 Temp-Comp Pll Ref Upgrade. ...I transmitted into a dummy load with 10 watts for a period of time. ... about 2 to 3 minutes at 10 watts and then the radio would reset itself with elecraft being displayed and the output power dropping to zero. Then after the reset, the power would return and then it would reset again. Here are some of the specifics. K2 with all of the options except the KPA100 Voltage and current on rx as displayed 13.4v at 300ma Voltage and current on tx (10 watts) as displayed 12.4v at 2.78a Good dummy load with low swr ATU in cal s so as to bypass it The problem appears to heat related because the time to failure is dependant on cool down time. Does anyone have any ideas? Thanks. Jason +++++++++++++++++