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Help with EZ80 rectifier

Son wants to build an audio amplifier using tubes. I'm a total noob when it comes to tubes. So we got ourselves a EZ80 rectifier and a few other tubes. First things first we wired up the EZ80 to the transformer. 4-5 Pins to 6.3VAC and Pins 1-7 both to 120V AC. The ref wire output of the transformer (120VAC ref) was grounded to the body. When switched on, we only get 62VDC at pin 3 (with body Ref) . Any idea why?.
 
Son wants to build an audio amplifier using tubes. I'm a total noob when it comes to tubes. So we got ourselves a EZ80 rectifier and a few other tubes. First things first we wired up the EZ80 to the transformer. 4-5 Pins to 6.3VAC and Pins 1-7 both to 120V AC. The ref wire output of the transformer (120VAC ref) was grounded to the body. When switched on, we only get 62VDC at pin 3 (with body Ref) . Any idea why?.
EZ80 is a fullwave rectifier where 1 and 7 is the two anodes. 3 is the cathode
What is your transformer ? Is it a single 120V winding with (120VAC ref) in the middle ?
 
Thank you for your replies.

I'm not able to do multiple quotes (New to the forum) but here are my replies.

@batteryman "Smoothing capacitor or inductor?"

- Not yet connected. We just measured the volts using a muti. Pin 3 to Red wire and Black to Plate.

@MarcelvdG "Are 1 and 7 shorted (half wave rectifier) or connected to opposite ends of a centre-tapped winding (full wave rectifier)? Was pin 3 loaded by something?"

- Pins 1 and 7 are shorted and given to 120V DC wire, the Ref wire (0VAC) is connected to plate. We have not loaded anything to the output of pin 3 (Open circuit).

@petertub "EZ80 is a fullwave rectifier where 1 and 7 is the two anodes. 3 is the cathode
What is your transformer ? Is it a single 120V winding with (120VAC ref) in the middle ?

- Transformer is 4 wire out. 0 - 6.3VAC (2A) (2 wires). 0-120VAC (2A) (2 wires).

I think i have wired it for half wave rectification. I will see if i can connect 1 and 7 to Ref and 120V AC. I will post a pic of the connection.
 
A half-wave rectifier without smoothing ideally produces an output voltage of √2/π times the RMS input voltage. That's about 54 V. You may get somewhat more due to the difference between the unloaded and loaded output voltages of the transformer, or maybe because the meter has some input capacitance. It should go to about 170 V...200 V when you connect a smoothing capacitor, still without load.

Is it a toroidal or an EI transformer? Toroidal transformers are normally not suitable for half-wave rectification.
 
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I've attached the following.

1. The circuit diagram
2. The photos of the transformer
3. Plate with the tube
4. Connection.

I apologize for the low quality of the photos. My son did most of the work and called me only when the problem arose. I think we messed up on the selection of the Transformer as its not center tapped. I'm basically from the solid state school of electronics and I don't understand why my son has taken a fascination towards tubes.
 

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I've attached the following.

1. The circuit diagram
2. The photos of the transformer
3. Plate with the tube
4. Connection.

I apologize for the low quality of the photos. My son did most of the work and called me only when the problem arose. I think we messed up on the selection of the Transformer as its not center tapped. I'm basically from the solid state school of electronics and I don't understand why my son has taken a fascination towards tubes.
Have you missed off the anode resistors?
 
Build this
bridge3.jpg

from here ....valvewizard.co.uk/bridge.html
Be sure to size the cap. according to the EZ80 data sheet...Cmax 50uF
Beware EZ80 Iout max....90mA
 
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As drawn that amplifier section won't work!! There are no load resistors! And your cathode resistors well are.....
What valves are you using? The more data the greater the help.
From what source is your circuit derived.
PS Welcome to vacuum tube audio.The journey is well rewarded :)