YAHA HELP

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I see three options:

- remove the regulator from the board and wire as shown in the wiring diagram (I feel like I'm repeating myself :D If something about the wiring diagram is unclear to you, could you turn that into specific questions?)
- leave the regulator on the board, take both of your current R5s off, put a 1K Ohm resistor in the place of R5. Connect your 12V DC line to the hole to the lower right of the regulator (the one that is connected with a short diagonal trace on the bottom). Then connect the left-most pin of the regulator to GND via a 5K Ohm resistor.
- use fa-schmidt's original regulator circuit. Regulator on board, R5 = 4.2 Ohm (or R5 and R5' to give 4.2 Ohm when paralleled), 12V DC line connected to same hole described above. No R6.

You may want to wait for Avro Arrow to confirm what I wrote above. I'm fairly sure it's correct, but he's certainly more experienced than I am.
 
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thanks dfy- I have taken the regulator off the board and wired according to the wiring diagram. Could you kindly take a look at it and tell me if I have it right. It still doesn't work but I do get a very quiet hum through the headphones. :scratch1:
 

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Errr... did you connect the two wires from the power supply both to the "+12V DC" holes?!? That's not what you're meant to do. Let's hope you haven't fried any parts.

You have to check your power supply first to check which of your two wires (black/red) is positive. That one goes to both "+12V DC" holes, the other one goes to one of the "GND" holes!

(The way you wired the regulator looks good. But why did you take off the heatsink?! That's gonna fry it when you leave it on for too long :( )
 
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In the original version, the LM317 was being used as a current regulator.
In the two schematics posted in this thread, the LM317 is being used
as a voltage regulator. Either was is fine, as long as you don't mix up the
value of R5. What is the value of the R5 resistor you have?
In the picture, the LM317 is wired wrong. LM317's are not very tolerant
of being wire up wrong.
 
The ECC83 has dual heaters at 6.3v each. the first one is between pin 4 and pin 9 then the other pin 5 and pin 9. Hence my explanation but the diagramme of the Ecc88 valve that I have is not clear; ECC88 @ The National Valve Museum
It looks to me like pin 9 is the centre of two 6v heaters. A resistance reading will confirm this.
I have never heard of 3v heaters, ( two 3v in series?). I apologies if I am wrong.
 
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In the picture, the LM317 is wired wrong...

Are you talking about OP's latest picture? Apart from the missing connection from Vout to the heater, the regulator wiring seems okay to me? (picture attached).

It looks to me like pin 9 is the centre of two 6v heaters. A resistance reading will confirm this.
I have never heard of 3v heaters, ( two 3v in series?). I apologies if I am wrong.
I have attached a part of the ECC88 Amperex data sheet. It would seem to me that the heater supply is internally paralleled (so they are two 6.3V heaters in parallel rather than two 3V heaters in series), and that Pin 9 is the internal shield, not a center tap of the heater. From there I would conclude that the voltage across the two heater pins is supposed to be 6.3V :confused:
 

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Because you mounted the 1K resistor "in the air", you are missing the connection from Vout to the PCB hole marked with green arrows in the picture below. (That hole connects to the heater via a PCB trace on the bottom of the board.)
 

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Well I have made the changes suggested by dfy and almost got it working. When I turned it on the dim light bulb flared quite bright went off, The regulator got very hot instantly and the right channel on my headphone got toasted. :eek:
Fortunately they were cheap earbuds and not good phones :D
I'm sure I've done something stupid here so once again I will need some help please :worship:
 

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Okay, so a few safety rules first before you plug it in next time:

Power it on without phones or source plugged in of course! Then check DC offset at the output (measure voltage between GND and both channels at the output) before plugging anything in.

As to what went wrong... I re-checked all your pictures again, and it seems you have a large solder blob that connects two traces that shouldn't be and therefore put the right channel of your headphones at +12V DC. See attached picture.

The regulator may or may not be dead after this. There may be more wiring/soldering problems, really do some extensive testing with a multimeter (for connections that shouldn't be there before(!) you turn it on and for sensible voltages after you turn it on, but before you plug in phones or sources).
 

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Hi- I cleaned up the solder on the board. The dc offset is 1.7mv on one channel and .7 on the other. This seems high to me :confused:
The LM317 gets very hot in a matter of seconds :eek:

No, those millivolts should be fine as a DC offset. I'm at a loss about the regulator getting super hot though. Either it's dead or there is a wiring mistake that I missed or don't understand correctly. Let's wait for someone else to weigh in on that.
 
Time for some basic troubleshooting.

What is the output voltage from the regulator?
With a 1k and 5k resistor, it should be 7.5 volts.
Even that seem pretty high. the tube should have
6 volts between pin 4 and 5 +- 15%. People usually
use 6.3 volts. If, as you said, the tube glowed very
bright and then went dark, the tube is trashed.

If the regulator is blown and putting out 12 volts, that
will be why the tube is blown.

You mentioned the offsets were 1.7mV and 700mV,
is that correct?

dfy has been giving correct advice. The picture in post 14
is how it should be wired.
 
Hi Avro Arrow-
It's not the tube which flared and went out. It's the bulb on my dim bulb tester. Sorry if I said that incorrectly. The dc offsets were 1.7mv and 0.7mv. I will check the other measurements and let you know what I come up with. Last night I put on a larger heat sick and left it on for about 10min and it didn't heat up as much as before; still quite warm though. The tube was glowing steadily while it was on.

Thanks for all your help
 
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