Pilot light on Melody tube amp

[glebert]

I got the isolation transformer wired in on my little Melody A-3L amp and it is sounding pretty cool (for what it is), but the pilot light has never been hooked up since I've had it. There was a 6.3V bulb in the screw type socket. Looking at the schematic it looks like it is supposed to be hooked up across half of one of the tube heaters. This would be fine for a 12AX7 type of tube but the 12AV6 tubes don't have a center tap on the heater. Any thoughts on what type of bulb should be in this and how it should be hooked up?

Thanks in advance,
Greg

[Jon Snell]

The heaters are all rated at 150mA in series. The 6volt lamp goes across the 5volt tapping on the rectifier.

[glebert]

The heaters are all rated at 150mA in series. The 6volt lamp goes across the 5volt tapping on the rectifier.

Thanks Jon, that makes sense now! I saw that the 35w4 had a tap on the heater but didn't look passed the diagram to see that the heater wasn't split symmetrically.

[novabell]

The power tubes have heaters that heat the tubes up to their normal operating temperature. You should wait a few minutes to let this happen before playing (putting a load) on the tubes. All electronic devices are damaged over time by cycling heat on and off, but tube equipment is even more delicate. They are similar to light bulbs: Light bulbs that are turned on and off repeatedly usually burn out faster than bulbs that are always on.

[mozz]

Same as a old radio which used the configuration. You will probably burn the tube out if no pilot lamp is there. If the tube is bad the pilot lamp will blow.

[glebert]

Same as a old radio which used the configuration. You will probably burn the tube out if no pilot lamp is there. If the tube is bad the pilot lamp will blow.

Amp is working fine now with the pilot light, thanks for all the help.

[novabell]

The power tubes have heaters that heat the tubes up to their normal operating temperature. Yaying (putting a load) on the tubes. All electronic devices are damaged over time by cycling heat on and off, but tube equipment is even more delicate. They are similar to light bulbs: Light bulbs Nox Vidmate VLC that are turned on and off repeatedly usually burn out faster than bulbs that are always on.

you should wait a few minutes to let this happen before pl