Gary is right on here. Even though my sample is small compared to the number of rigs some of the others here have worked on, EVERY SINGLE 7-line radio that I have worked on has had at least one problem related to oxidized Molex pins. A first step with troubleshooting any rig should be re-seating the boards.
73 -Jim On Mon, 22 Mar 2010 15:25:19 -0400, Garey Barrell wrote: >Chris - > >Even MOLEX pins that 'look like new' can still have enough oxidation to >interfere with the minute currents involved in these radios. If the 5V >supply to the Parent Board is 4.67V, then something is dragging it down, >most likely leaky electrolytics. > >It's always a good idea with these rigs to slightly unplug each card and >connector with power OFF, and 're-seat' them before going too far >troubleshooting. Just doing the connectors will 'solve' about 80% of >TR-7 "problems". > >73, Garey - K4OAH >Glen Allen, VA > >Drake 2-B, 4-B, C-Line& TR-4/C Service Supplement CDs ><www.k4oah.com> > > >Chris Hughes wrote: >> Thanks for the tip , the MC7805 is runing hot , but checks out ok , as >> is the MC78L24C , ill check the other voltages and see whats happening >> , the Molex pins are all like new .... >> > >_______________________________________________ >Drakelist mailing list >[email protected] >http://mailman.zerobeat.net/mailman/listinfo/drakelist -- 3/21/2010 "So this is how liberty dies... with thunderous applause." (Padmé Amidala, "Revenge of the Sith") _______________________________________________ Drakelist mailing list [email protected] http://mailman.zerobeat.net/mailman/listinfo/drakelist
