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Well; here we go. Seems I am blowing fuses upon switching my unit on. I have gone over the trans and PS wireing and it all checks out and looks good. Can a shorted lead on the CCS cause a fuse out on power up? The tranny is Blue/Red secondaries to the anodes of the 6CA4(250V) Red/Yellow to chassis ground Yellow 5v secondaries to the Filament heater pins of the rec tube Cathode to the choke Choke to PS cap + The two primary black wires/ one to the AC input and the other to the switch Then from the switch to the fuse to the AC input neutral return
What amp fuse are you using? Slow or fast blow? I'm started with a 2A slow blow and it worked fine. Are you blowing as soon as you switch on or is it when the rectifier heats up?......Colin
this thing ought to be consuming about a half amp from the wall. However, there are going to be transients at switch-on which could easily exceed this amount. By a lot.... Slo-blo is the way to go. an amp or amp and a half should do quite adequately. If you have a 500 mA fast fuse in there I am not suprised you're toasting them... regards, Douglas
the 6CA4 is a 6.3 volt heater. Don't worry too much, I suspect you'll get a nice slow warm up and gentle application of HV. Check its cathodes colour compared to the 5687, you might want to put the 6.3 winding on it. regards, Dogulas
Are you hooking the red/yellow (center tap) to the chassis or the the signal ground path (opposite side of cap on B+)? The CT (or any of the HV supply) should not be in contact with the chassis. Are you using a 3-point (hot/neutral/ground) electrical connection from the wall outlet? I should have pictures of Guinevere up tonight. Amazing, FedEx actually found my house on the first try today and brought dad (OK, mom) a new toy ......Colin http://audioroundtable.com/GroupBuild/messages/210.html
Well, I used the 6V4 with the 5V tap. Turns out the 6V4 should be run off 6.3V. It works well with the 5V but I will up the voltage. Thanks for pointing this out. I should have paid more attention.....Colin http://tdsl.duncanamps.com/show.php?des=6V4