I have a magnifying glass and a bright light, so I should be able to see pretty good down there. I do know the area (back of the cap near the tube) where the problem is occurring, so that will help also.
“.....and an improperly adjusted tension/spacing nut on the rear.” I saw that nut and wondered and wondered what its function was. Thanks for all the info on where to look at. I will keep the group informed. Roger White W5RDW Murphy, Texas From: K9sqg Sent: Sunday, July 29, 2012 9:39 PM To: rwhitete...@verizon.net ; drakelist@zerobeat.net Subject: Re: [Drakelist] Removing the Load Variable Capacitor on a L-7 Roger, It is hard to diagnose something like that without a visual inspection. If it were my amp, I would open it up and look everywhere to see what is what. My experience is that when you go in to fix one problem, you often find more problems. Particularly if "somebody has messed with it". As to the load capacitor, inspect it to see if the rotor plates are centered within the stator plates. Inspect them with a bright flashlight to look for pitting. Inspect the ceramic insulation for cracks, loose mounting bolts for the stators, and an improperly adjusted tension/spacing nut on the rear. Too, see if any screws are missing from any of the places where subassemblies are held together, etc. Please keep the group posted we all can learn from it. 73, Evan, K9SQG -----Original Message----- From: Roger White <rwhitete...@verizon.net> To: drakelist <drakelist@zerobeat.net> Sent: Sun, Jul 29, 2012 9:54 pm Subject: [Drakelist] Removing the Load Variable Capacitor on a L-7 I have had a Drake L-7 sitting on the shelf unused for a few years now and recently decided to sell it. It has had the power supply updated and the ON/OFF switch disassembled and cleaned. It had functioned OK the last time I had used it (2 years ago) with the only problem being an erratic reading Plate Amp meter (an quick tap on the meter made it come from “zero” to the correct reading). The problem I am having now (and one that has never occurred before) is the Load Variable Capacitor is appearing to short some of its plates over a narrow arc of operation (say 10-20 degrees of arc). I can hear the plates touching and, of course, the resultant negative effect of the power out going to zero, etc. I have only had the amp open once to clean the power switch, I could tell it may have been worked, on as far as the screws on the bottom cover(s) appear to have been removed at few times. One thing I have noticed as I looked at the cap with the cover removed is that I can hear the plates “unshort” if I “torque” the chassis a little bit or loosen the screw that holds the front half of the Load Cap to the floor. Has anyone had this sort of problem with one of the variable caps? Can the Load var. cap be removed easily? Thanks for any help in advance. Roger White W5RDW Murphy, Texas _______________________________________________ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
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