too much preamp voltages

[yalesmith]

no readings just zero resistance

[Firestorm]

How about resistance from the ground end of the turrets where the cathode resistors are connected to the minus end of the filter caps?

[yalesmith]

again there is no resistance it is a zero.

[yalesmith]

no resistance...is that a bad thing? I am just a little green and a bit ignorant too theory

[Firestorm]

The cathodes have to be grounded (through a resistor for bias) in order to conduct. I was just checking to be sure you had solid grounds.

SO:

1) The plate resistors have supply voltage and the plates themselves have voltage, but it is the same as the supply; no drop.

2) The cathode resistors are well grounded, but show no voltage.

This might happen with dead tubes or if the tubes are not heating. You have AC voltage on the heater pins, but are the tube filaments lighting up?

[yalesmith]

OK ...the filaments are not lighting up! now what? the voltages are 3.2 v ac on pins 9 and 4/5 of the preamp pins...the rectifier and power tubes are lighting up and those voltages are okay.

[Firestorm]

Could you post a photo of all the filament wiring, especially the connection from the output tubes to the preamp tubes. Also see how may AC volts you read from pins 4/5 to pin 9 on the preamp tubes.

[greekie]

Please, please check, that you have wired the sockets right. I can't follow the wiring under the board, but it looks like you have miswired some of the sockets - e.g. plate lead on grid, etc.

See if there's anything to that claim. It could have damaged the tubes.

[yalesmith]

I switched out the tubes, so I am sure the tubes okay.

[Tillydog]

OK ...the filaments are not lighting up! now what? the voltages are 3.2 v ac on pins 9 and 4/5 of the preamp pins...the rectifier and power tubes are lighting up and those voltages are okay.

...see how may AC volts you read from pins 4/5 to pin 9 on the preamp tubes.

^ Do this ^

Likely you have a break in one side of the preamp filament wiring and you are measuring the same 3.2V at either end of the filament. The above measurement will tell you if this is the case.

Andy

[surfsup]

Yea and it doesn't read 6.3vac between 9 and 4/5, you can test continuity of the runs that go between the last power tube and the PI. Since the preamp/PI are not lighting up, but the PA is, I'm thinking the break has to be between the PA and PI?

[Firestorm]

Easy to tell if it's a break: pull the preamp tubes and power up. If there's a break in continuity, one side won't show any voltage. I was also thinking that with all the color changing wire (why did you do that?), you might have managed to wire both sides of the preamp heaters from same side of the heater supply. That would still show 3.2VAC on all the pins, but would not heat the tubes ('cause it's in phase). Start by measuring AC between pins 4/5 and pin 6. If it's 6.3~ volts, then I'm stumped.

[yalesmith]

There was a break and I was thrown because I got continuity. I replaced the wires going from the PT to the PI and it litt right up. This was such a silly mistake that i am a bit embarrased. Funny, I started thinking it was something more complicated than is actually was. I am such a dummy but thanks for all the help!

[gingertube]

Join the club - no need to be embarassed, I for one have had the exact same problem. In my case some tubes lit, some did'nt, it turned out that where I joined wires at one socket the wire insulation had prevented a proper connection and hence a break in the heater chain. Took me ages to find it.
So instead take satisfaction from your "learning experience".
Cheers,
Ian

[Structo]

Usually the heaters are wired so they are in phase.

The filament supply is AC (alternating current) with positive and negative wave forms.

What that means is you use two different colors of wires like you did but you connect the red side to, say pins 4&5 and the blue to pin 9 on down the line.
Keeps everything happy.

That is supposed to reduce noise a bit.

The power tubes are not as critical but most of us keep the same color on the same pin of each power tube.

Hope that makes sense.

I know even Kenny didn't do it all the time so maybe there is some m0jo in it.