Orange AD30 tube issues

[Jerm]

Hello all! Its been a while since ive been on so I hope everyone is doing well. I am currently working on an orange AD30 and Im at a wall and need help troubleshooting the issue. Only 2 out of the 4 power and pre amp tubes are glowing. Ive moved the tubes around and its always the same sockets that arent working. Any ideas?

Thanks!

[olddawg]

Hello all! Its been a while since ive been on so I hope everyone is doing well. I am currently working on an orange AD30 and Im at a wall and need help troubleshooting the issue. Only 2 out of the 4 power and pre amp tubes are glowing. Ive moved the tubes around and its always the same sockets that arent working. Any ideas?

Thanks!

If they are PCB mounted tube sockets make sure that the connections to the pads have not cracked due to heat and vibration. If the filament voltage is present on the socket connections and the tubes aren't lighting up you will have to retention the sockets or replace them.

[MarkusBass]

Have you checked voltage on sockets?
Does the board look similar to this one (this is different model)?

Did you look at the wires connected to sockets?

Mark

[Jerm]

If they are PCB mounted tube sockets make sure that the connections to the pads have not cracked due to heat and vibration. If the filament voltage is present on the socket connections and the tubes aren't lighting up you will have to retention the sockets or replace them.

Solder joints are ok. No cracks or clouds. I do notice no voltage to the filiments on one side.

[Jerm]

Have you checked voltage on sockets?
Does the board look similar to this one (this is different model)?
[ATTACH=CONFIG]15642[/ATTACH]
Did you look at the wires connected to sockets?

Mark

Htr10 wires look charred but also rewired to bypass a melted 2 pin connector. ( that side is the glowing side ) htr9 wires look fine ( this is the side not glowing ). The power lamp is not getting voltage so it appears that the amp is not on when it actually is. Lamp is fine voltage is at 0.

[Jerm]

Bump**

[MarkusBass]

Htr10 wires look charred but also rewired to bypass a melted 2 pin connector.

Doesn't this explain the problem? Can you post a photo? I think that in this amp heaters are connected in exactly the same way as on the photo I posted previously; with twisted wires and DC sockets connected to valve sockets. So either the wires are melted, or DC sockets are not contacting correctly. Alternatively everything is OK but the valves are dead. This can be simple verified with DMM. A photo would help.
Edit: older Orange amps had separate windings for preamp and power amp valves. I would also look whether there are any fuses (possibly open).

Mark

[Jerm]

This is where I started. so, yes, one would assume this is or was the problem. but the head scratcher is that the windings affiliated with the charred/rewired side is the side that appears to be working fine. Its the other windings side where the filaments are not glowing.

[olddawg]

This is where I started. so, yes, one would assume this is or was the problem. but the head scratcher is that the windings affiliated with the charred/rewired side is the side that appears to be working fine. Its the other windings side where the filaments are not glowing. [ATTACH=CONFIG]15654[/ATTACH]

I don't have a schematic, but you will need to find the filament source(s) and measure them. If the source(s)is there then it is a simple matter of finding the spot where you lose it with your dvm.

[MarkusBass]

This is where I started. so, yes, one would assume this is or was the problem. but the head scratcher is that the windings affiliated with the charred/rewired side is the side that appears to be working fine. Its the other windings side where the filaments are not glowing. [ATTACH=CONFIG]15654[/ATTACH]

It would help if you'd make a photo of the bottom of the board. And also if you explain what was done with the yellow and black wires. Looking at the photo I'd say that the wires are not connected correctly. The two diodes are most probably 1N4007 and they are in high voltage power rail (>300V). So I wonder why the yellow wire is soldered there. I think that the task here is very easy: you have two (or three including ground) wires for the high voltage supply (should be most probably connected to these diodes) and two (or maybe three) wires for the heaters and you should identify them. After this you will be able to draw a schematic and check whether the wires are connected correctly. It seems to me that you have one wire from the heater circuit shorted with high voltage rail.
BTW, doesn't this look similar?

This is another Orange amp. You have to be sure that the board is not conducting and there is no short to the ground.

Mark

[Jerm]

I don't have a schematic, but you will need to find the filament source(s) and measure them. If the source(s)is there then it is a simple matter of finding the spot where you lose it with your dvm.

With over the top usage of hot glue over each htr connecter its near impossible to test the wires. With continuity test on my dmm all 4 wires connecting htrs 1-10 are all reading as if shorted together.

[Jerm]

This might help a little. If not bare with me as I try my hardest to explain the process. The main board is pc134 and the valves that are not glowing are v2,v4,v7,v8. Test point 9 is reading 11.8v. Test point 10 is reading 0v. Also channel two is not working at all but channel one seems fine.

[Jerm]

Hey mark, the yellow wire that is soldered to the diod is fine. The trace runs from the diode to the pin where the yellow wire was originally connected to. It's all on the same trace.

[olddawg]

With over the top usage of hot glue over each htr connecter its near impossible to test the wires. With continuity test on my dmm all 4 wires connecting htrs 1-10 are all reading as if shorted together.

You can usually soften hot glue with a heat gun or even a blow dryer. Continuity is a valid test proceedure but it will not tell you if the supply is not present or shorted to ground. If at all possible measure then follow the filament supply sources and circuits with the amp on. Make sure you have a speaker or dummy load connected.

[MarkusBass]

Hey mark, the yellow wire that is soldered to the diod is fine. The trace runs from the diode to the pin where the yellow wire was originally connected to. It's all on the same trace.

I can see that on the photo but I was wondering why the black wire is connected there.

The main board is pc134 and the valves that are not glowing are v2,v4,v7,v8.

There is a simple test that will clarify the issue.
1. Remove all valves to be sure that you are not taking false measurements by measuring valves.
2. Check for continuity between working valves e.g. between pin 4 of V5 and pin 4 of V6. The same with pin 5 of V5 and pin 5 of V6. I'm sure there will be continuity.
3. Check for continuity between not working valves e.g. between pin 4 of V7 and pin 4 of V8. The same with pins #5. Most probably there is a continuity (if not, just check why).
4. Check for continuity between one working valve e.g. V5 and one not working valve e.g. V7. Check between pins #4 and #5. Most probably there will not be continuity.

The problem here is that valves in this amp are supplied in two rows; V1, V3, V5 and V6 are together in one row and V2, V4, V7 and V8 are together in the other row. In your case it means that one of the rows does not get 6.3VAC supply. It means that either one wire from the transformer to the first valve in the row is not connected or one wire in the connection chain is melted or not connected.
If you don't want to remove the glue from the plugs, you can use needles or simply measure the continuity directly on the sockets of the valves.

Test point 9 is reading 11.8v.Test point 10 is reading 0v.

I think that this is irrelevant in this case. You have to find out 6.3VAC on every valve socket. And this is very easy because if v5 and v6 are working, the voltage is on pins 4 and 5. The same should be with V7 and V8 but most probably it's not.

Also channel two is not working at all but channel one seems fine.

This is simply because one row of the valves does not get 6.3VAC to heaters.

Mark