5F6A Build Has LOUD Hum and NO Amplfication

[5F6Afirstbuild]

The meter was set to measure AC Volts. There is a green/white wire that is grounded..no green/yellow.

And should the standby switch be off but the power switch on?
Thanks for your advice

[loudthud]

And should the standby switch be off but the power switch on?

That is correct. The high voltage didn't need to be on for that test, it's always safer if it's off when it doesn't need to be on for the test. You can still damage the transformer if you accidentally short one of the green wires (or just about any other transformer wire) to ground. This can happen at the pilot light if you try to remove the lamp when the power is on.

Just to double check, with the Power and Standby switches OFF, measure the ohms to ground of the green wires. They should measure less than one ohm.

Is the pilot light nice and bright? It should make a nice white light, not red or orange. Maybe your meter just doesn't measure low amounts of AC voltage accurately. You should be able to see the heaters in the tubes. They should be glowing red or orange.

Try to read the DC voltages on the other tube socket pins to ground. Both switches ON for this test. Pin 5 of the 6L6 tubes will be a negative voltage, other voltages should be positive, up to 450V or so. Be careful, it's a good idea to just use one hand and stick the other in your pocket. Don't touch the chassis.

Most people call the tubes by number. V1 is nearest the input jacks, V4 and V5 are the 6L6s and the rectifier is V6. We don't need the voltages on V6, the other voltages will tell us if it's working.

[5F6Afirstbuild]

Alright I'll get on that and let you know.
The light is really bright and i can see the heaters.

Again, I really appreciate the thorough advice.

[5F6Afirstbuild]

I was testing all the tubes (tried to post this last night but looks like it did not post for some reason). . .and heard that crackling sound again when I got to V3. This time when I plugged in a guitar it worked and sounds great . . .but only on Bright, nothing on normal channel.

I stopped testing after since I did not want to undo something I had done:
They seem crazy

V1:

1: 187
2: 0
3: 2.2
4: 0
5: 0
6: 0
7: 2.24
8: 2.29
9: 0


V2:

1: 187
2: 0
3: 1.3
4: 0
5: 0
6: 355
7: 187
8: 197
9: 0


V3:

1: 388
2: 0
3: 46
4: 0
5: 0
6: 0
this is when it crackled


Thanks again. ..

[g1]

Here is the Weber schematic for reference: https://taweber.powweb.com/store/5f6a_schem.jpg
You are showing 0V for pin 6 of V1. Please recheck. It should be almost the same as pin 1. It would make 1 set of inputs not work. Although the schematic and layout show the bright inputs going to the other half of V1. Check the layout.
V3 pin 6 is missing it's supply voltage. Check the voltage at either end of R40. Probably an intermittent connection somewhere causing the lack of voltage at V3 pin6. Your probing restored the connection. Maybe at pin6 on the V3 socket.

[loudthud]

Resistance measurements need to be made with the Power and Standby switches off and the caps discharged. It's a good idea to unplug the amp from the mains to be on the safe side.

V1: Pins 3 and 8 are supposed to be connected together so they should have the same voltage. Check your connections.
　
Pin 6 shows zero volts. Refering to the schematic R22 and R23 get their voltage from node D and we know R22 is working because the voltage at pin 1 is correct so either R23 is broken, has a bad connection or there is a short to ground at pin 6. Measure the resistance of pin 6 to ground. A short to ground will measure one or two ohms. If everything is normal pin 6 will not give a stable reading to ground because the capacitors in the circuit will confuse your meter, but you won't measure a short.
　
V2: Voltages look normal.
　
V3: Again pins 3 and 8 are supposed to be connected together and should have the same voltage. Check all solder connections. Pins 2 and 7 are a special case where touching the meter probe to them will affect the circuit and give a false reading. You can just skip measuring those. It's normal to get a loud crackling when measuring those pins.

Any wire should have the same voltage on each end, unless the wire is broken inside the insulation where you can't see it. You can also test this with the ohm meter. Look at the layout and test the continunity of any wire that connects two points on the backside of the board or where a wire that goes to a pot or tube socket connects on the backside of the board. Make sure that wires don't touch the chassis or anything else after they solder to a tube socket or pot terminal.