Building A Stereo Tube Amp

Step 9 The Build: Testing and Finishing Up

So once you've put it all together it's time to see if it actually works. However, don't plug it in directly into the wall at first, because if you do and you've made some wiring mistakes, you could end up frying some components. If smoke comes out of it, that's probably not a good sign. You could use a power adapter for a phone or some other low-ish voltage device to check everything first. Connect this to the terminals of the power socket and use a multimeter to test the points on the schematic where the voltage is indicated. With a power adapter like the one pictured, the voltages should be off by about a factor of ten or so. If everything looks basically right, go ahead and plug it in and hope that nothing bursts into flame. Once the power supply is behaving, hook up some speakers and see how it sounds. Keep poking around until it works, but be very careful (check the Intro if you don't know what I'm talking about).

Comments

[Pentagrid]

An alternative to the plug pack could be an ordinary light bulb in series with the amp's mains wiring. I use such a device when plugging in old Radios for testing.

[Ceriand]

A variac would work well here. It lets you bring up the line voltage gradually and can supply more current than a wallwart. You can get them for like $50 at a place like Fry's.