Almost no voltage coming out of rectifier tube

[cavinccr]

Thanks in advance to anyone taking the time to reply.

I am working on a little single el84 build (basically a Kalamazoo Model 1), which is my first full build. I have the circuit wired but when I went to test voltages, I found only about 2.9 volts was coming from the 6X4 rectifier. The heater wiring is the correct voltage throughout. The AC into the rectifier is about 545vac, which is just a bit high. Troubleshooting, I replaced the tube twice and then tried a solid state version of a 6x4. I then replaced the tube socket twice. Now I'm left rather stumped so I'll gladly try any suggestions.

Since I'm quite new to this I'm hoping this is simply a "Silly newbie you have a lot to learn" situation so if any criticisms are due I'll take those to heart. Thanks for your time.                                                                                                                                                                         

[sluckey]

You say you have 545VAC into the rectifier. Are you measuring this between pin 1 and pin 6 of the 6X4?

Do you have the transformer center tap connected to chassis ground? How much AC voltage do you measure from pin 1 of the rectifier tube to chassis? How much from pin 6?

Show us your schematic. Maybe post some pics of the amp.

[Colas LeGrippa]

You prob. forgot to fill the rectifier tank with jet fuel, I'm pretty much sure. Once it's done, don't forget to prime it twice

[Colas LeGrippa]

...post a schem with voltages and we'll solve the problem, promised.

[PRR]

> I found only about 2.9 volts was coming from the 6X4 rectifier.

Did you switch your meter from AC to DC?

The transformer side is AC. The rectifier and cap is big DC with small AC riding with it. It would be reasonable, for some meters, to show a few V AC here. We really want to see like 300V DC. The AC is of no interest.

[jjasilli]

Either that, or maybe there's a short.  I would disconnect the lead from the tube socket lug for the output pin of the 6X4; then see if there's proper DC voltage on that lug.  If yes, then there's a short somewhere downstream in the B+ rail.  In that case the chassis might be "hot" (i.e., at high voltage) & present a shock danger.  Another option is to use the light bulb limiter test.

[Colas LeGrippa]

The a/c is of big interest I would say, because we put pi filters and chokes in our amps to get rid of it....


Colas

[shooter]

we put pi filters and chokes in our amps to get rid of it....

hence;

The AC is of no interest.

 Gotta love side-ways logic

[Colas LeGrippa]

LOL