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Hello, this is my first amp build. I clearly have done something wrong, but I'm not sure what it is.

I put together the Plexi and hooked it up to a speaker output. I got a staticky ticking sound when it was turned on, but no guitar sound.

I'm now checking voltages and with only the rectifier tube in, the preamp and power amp plate voltages are all around 430V DC. On the rectifier tube, here are my voltages:
Pin 1=318V AC
Pin 3=442v DC (I think)
Pin 7=318v AC

I'd appreciate any suggestions you might have for what to look for.

The first thing people are going to ask you is for good close ups of the inside and a little more info. Help will come

Thanks @stetterhawk. I am uploading some pics now. I thought the voltages might do it because the preamp tube plate voltages are a lot higher than what was listed in the directions ( ~150-250V).

The photos are coming. Is there any other info I can provide?

Here is a link to Gut Shots.
https://goo.gl/photos/hYtTzpSxW6e25BqJ8

Overview Photo Below

Voltages will read high with no tubes in place. With no loads all the voltage dropping resistors won't do much. Your readings at the rectifier socket look OK.

Recheck your wiring. Make sure all the parts are in the right place. Check all your solder connections. They look good in the photos, but check that they are all solid. Make sure nothing is shorted, especially the shielded cable.

Put the tubes back in and read the voltage at all the pins. Post these readings. It will help us narrow down the problem.

Good luck with the amp.

Mitch, I'll recheck wiring tomorrow AM when I am fresh. In the meantime, here is the latest:
This time when I hooked up the amp to the speaker and powered it up, it was silent....but when I moved it around the ticking and periodic static came back. Initially the static only was there for a moment when I moved things around...then it just stayed around.

Check of voltages revealed that pins 6 and 8 on V1 are off. I am not sure why pin 8 registers as 4.96 because I checked turret board by R5(?) and it was just over 1V as expected.

Here's the full set of voltages:
V1 pin 1,3,6,8=
1.52
1.04
280
4.96

V2:
173
1.89
281
174

V3 pins 1-3, 6-8:
198
57
89
211
60
89

V4: pins 7 & 9
351
345

V5: pin 7
351
[I did not get voltage at 9; I was a little confused due to inconsistency in manual's instructions on which pins to check for the EL84s ]

V6: pin 1, 3, 7
310
371
310

Please let me know if any of the voltages look bad to you or if you have suggestions on what to check. Thanks for your help!

I found a bad joint for turret connection to V1 pin 4 and fixed it. Also fixed a bug at the input. Good news is, I now have sound from the 1 tone knob channel!!!

The bad news is that I still have a staticky noise, like a fast paced ticking sound. Also, the TMB inputs do not work.

I'm sure the problem with the TMB inputs is related to my wiring job, but any ideas on the ticking noise?

At this point, I've got both channels working...IF the impedance selector is set to 4 Ohms. If I set to 8 or 16 Ohms, nothing. When set to 4 I still get the ticking noise.

**EDIT: I caught a missing connection b/w pin 3 of V4 and V5. Fixing that didn't change the problem**

The odd thing is that, when it's turned off, continuity tests show connectivity between all 3 OT taps at the switch and the red (hot) points and chassis ground. So I'm not sure how the signal is getting to the output at the 4 Ohm setting.

I feel like I'm so close! Any help would be really appreciated.

The output switch looks like it's wired properly in your photos. With no speaker connected, do you get a really low resistance reading between hot and ground on the output jacks? Try each setting on the switch. The reading should vary a bit from one position of the switch to the next, with the highest reading on the 16 ohm position.

If you don't see this, and your connections to ground, the jacks and the switch are good, then the output transformer is bad.

You can verify this by measuring the resistance from the black wire to the yellow, green and orange wires and you should get the results mentioned above.

As for the ticking sound, do any of the pots make it louder or quieter? Does moving the amp to a different location make a difference? Maybe it's picking up noise from lighting, other electronic equipment, or machinery nearby.

Also make sure everything that's supposed to connect to ground actually does and you have a good connection to the AC ground.

Thanks for takinga look at the photos Mitch!

So when it is turned off, set to the 4 ohm position, and no speaker connected, I get a reading of .8 Ohms between the hot and ground. When I go to the 8 or 16 positions, I get infinite resistance.

I think the connections to ground, jacks, and the switch are good. I get about 1.1 Ohms resistance between Ground and 16 Ohm switch lug. It goes down to about .8 Ohms at the 4 Ohm lug. But I would be surprised if the OT is bad--is that a rare occurrence? Would you suggest any other tests to confirm that it is the OT that is the problem?

Regarding the ticking and static noise: It's pretty audible even at very low volume/gain settings and if you turn up the volume/gain. a loud bassy hum becomes apparent. It's possible that the outlet is poorly grounded--I can test it on a different outlet if you think that could be the culprit.

The resistance readings look good. That's about what you should expect. If you measure continuity between black and each of yellow, green and orange, the OT is good. Yes, it's rare for them to be bad.

If you don't see the same readings at the speaker jacks, then the switch could be bad or you don't have good connections for the 8 and 16 ohm wires.

Try measuring from the common terminal of the switch to the three lugs where the transformer wires connect. Pick parts of the lugs where there is no solder or flux. It should read pretty much 0 ohms for each position. If it doesn't, then the switch is bad.

If the switch measures good, then re-do the solder connections for the 8 and 16 ohm lugs. Sometimes solder connections look good but they are actually cold joints.

Just back from a trip and now getting back on the amp. If I understand what you mean, I checked from the metal tip that moves onto different terminals depending on the position of the switch. Resistance to each of the terminals was about .4 ohms, but I think that's as close to zero as my DMM will get. When I touch two points on the chassis I also get .4 Ohms,

https://goo.gl/photos/fgRc8PfCaUAxuYUX7
As you can see in the linked image, I have the indicator light wired to the terminal strip and have that connected to the black wire that twists around the white one. Should I re-do the wire so that there's a single wire running from the LED indicator all the way to the "N" lug?

One more thing: Remember when I said:
"The odd thing is that, when it's turned off, continuity tests show connectivity between all 3 OT taps at the switch and the red (hot) points and chassis ground. So I'm not sure how the signal is getting to the output at the 4 Ohm setting."

Actually this is only true when the switch is at the 4 ohm setting. When the switch is at 8 or 16, I get no continuity between any points. My intuitive understanding is that the red wire should be continuous with the terminal that is selected with the switch right? If so, does this mean the switch is bad?

Your resistance readings from the common terminal of the switch to the other three terminals indicate that the switch is good.
Earlier resistance readings of the various windings on the OT indicated that the OT is good.
Try resoldering the connections to the 8 and 16 ohm terminals on the switch.

You should see your .4 ohm reading (or the same reading you get when you short the two meter probes together) from the common terminal on the switch out to the hot terminals of the speaker jacks for each position on the switch.

The image in your last post about the indicator light didn't show up for some reason.

Dear Mitch, thank you I edited the post so that the photo is linked and the link is also below. I'm wondering if it is bad that the power switch is connected to the black wire via the terminal strip. I did that I did not cut a long enough piece of black wire, but if you think that is a problem, I have enough of the other colors that I can run a continuous line from the switch to the "N" lug. Let me know what you think. Thanks!

https://goo.gl/photos/fgRc8PfCaUAxuYUX7

It's not the neatest AC wiring I have seen, but it looks like it will work. You can change the black wire if you want, but it should work fine the way it is going to the terminal strip.

OK, so I've redone the joints at the 8 and 16 ohm lugs but those connections still don't work.

Also, I re-did the black wire to omit the terminal connection, but as you suspected, that didn't affect the ticking.

I checked what happens if you pull out tubes. The ticking remains in all cases except if you pull out V3. However, with V3 out, there was also no guitar sound, so I suspect that may not be so informative.

Any other ideas to try out? Would voltages help?

If you suspect your OT for some reason, you can do a resistance check to get an idea of it's health.

Disconnect all the wires from the circuit, then use a digital ohm meter to measure the following resistances.

Primary
Brown - Red: 275 ohms
Brown/White - Red: 160 ohms
Blue - Red: 331 ohms
Blue/White - Red: 166 ohms
Brown - Blue: 606 ohms
Brown/White - Blue/White: 326 ohms

Secondary
Black - Orange: 1.0 ohms
Black - Green: 0.7 ohms
Black - Yellow: 0.6 ohms

_________________
Stephen
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Sorry to be dense, but can you clarify which wires should be disconnected? Do you mean that I should disconnect the output transformer wires from the rest of the amp?

Thank you!