Well, all the data for the aforementioned optimization is collected and in the computer. I’ve been chewing on the data and my notes for the last couple of hours and it’s safe to say, there is a lot more here than first meets the eye.
Continue readingWe’ve had a bit of a cold and rainy snap here which has prevented me from getting to the chassis work for the new 807 amp. But that doesn’t mean I’ve been totally idle.
Continue readingMy last post concerning unused and little used test equipment got me thinking. I decided that maybe some of the equipment I’ve accumulated over the years should really be put to better use.
Continue readingIt never ceases to amaze me how much test equipment I have seemed to have accumulated in the last 40 years or so. And some of it has been largely overshadowed by the continuing march of technology. It seems that everything now is so feature packed that lots of the old equipment is (nearly) totally obsolete.
Continue readingA comment by “Dave K” a few days ago got me thinking about how I intend to run my 807 power stage and the limitations listed on the data sheet. So it shouldn’t be a shock to anyone that I’ve decided that a little more testing is required. And that required an update of my 807 test jig.
Continue readingI’ve finished modifications to my test jig to allow the testing of the 6BQ5/EL84. It’s really a shame that so few other 9-pin power pentodes use the 9CV pinout. The 6CW5/EL86 is the only other really common one.
Continue readingIt really is amazing how much I can accomplish when suddenly I can’t work on all the projects which have been keeping me busy for the last month. The SSU assembly is complete and I’ve done some testing.
Continue readingAs it turns out, there is a crew working on painting the exterior of my house today. Since I can’t work on many of my outdoor projects around the house, I thought I’d take the opportunity to get a little done on the source selector unit.
Continue readingIt took a while but the DC checkout is complete and I’m finally ready to finish assembly on the Source Selector Unit.
Continue readingThe resistors for which I’ve been waiting showed up this afternoon. Time to get back to work on the Source Selector Unit.
Continue readingAs I said before, I decided perform the DC testing of the tube assembly for the source Selector Unit in the clamping fixture. But just as I started testing, I ran into a little problem.
Continue readingYesterday I was bottling mead but today I got a chance to wire up the buffers and tie in the coupling capacitors. This completes installation of all the signal chain components. All that’s left on the assembly is the final power supply wiring.
Continue readingHere’s the salient point about putting your entire amplifier design and build process on the internet for all to see. Invariably, regardless of how well everything is going, things always arise which manage to keep you humble. And today it happened again.
Continue readingI got a chance to do a little work on the amp today. I managed to install the top plate on the spalted alder chassis, install the filter inductors for the power stages, connect the output transformer secondaries to the speaker terminals, and wire in the power transformer primary and indicator light.
Continue readingIn the last few days I’ve managed to get most of the wiring on the 6L6 SE-UL top plate complete. This includes all the preposterously large power supply filter capacitors.
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