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GU81M glass defect (?)
GU81M glass defect (?)
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Old 19th November 2019, 09:20 AM   #1
NiaDebesis is offline NiaDebesis
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Default GU81M glass defect (?)

Hi,

I am not new to the forum, but I don' t remember my old email and nickname.
Bere Is my question.

I bought an GU81M in pristine condition for 35usd but It appears ti have an helicoidal junction in the middle of the glass evelope.
I have made a photo with a light perpendicular to the tube to show the imperfection, also the two parts are not at the same level.

The seller gave me a refound for other reasons, but I'd like to know of it's normal or not.

Thank you all
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Old 19th November 2019, 02:59 PM   #2
Kay Pirinha is offline Kay Pirinha  Germany
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I'm quite sure that it isn't a crack and won't affect the tube's performance.
Best regards!
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Old 19th November 2019, 04:12 PM   #3
NiaDebesis is offline NiaDebesis
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Quote:
Originally Posted by Kay Pirinha View Post
I'm quite sure that it isn't a crack and won't affect the tube's performance.
Best regards!

I thought that when they closed the glass they pulled the tube wrong from the lathe and due to the temperature of the glass they engraved a marking in the glass.

Is reasonable?
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Old 21st November 2019, 06:13 AM   #4
VladimirK is offline VladimirK  Uzbekistan
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If it will be needed, I can offer ceramic sockets for GU81M. 2pcs, used, but in very good clear state, with complete set of metal bracing around the ceramic base. I was looking for these sockets very long time, since had 6pcs of GU81M and planned project. But it seems not realistic for me now. Expensive and not enough time.
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Old 21st November 2019, 07:16 AM   #5
NiaDebesis is offline NiaDebesis
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Quote:
Originally Posted by VladimirK View Post
If it will be needed, I can offer ceramic sockets for GU81M. 2pcs, used, but in very good clear state, with complete set of metal bracing around the ceramic base. I was looking for these sockets very long time, since had 6pcs of GU81M and planned project. But it seems not realistic for me now. Expensive and not enough time.


Hi,

How much do you charge for a piece and two pieces?
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Old 21st November 2019, 08:59 AM   #6
VladimirK is offline VladimirK  Uzbekistan
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Quote:
Originally Posted by NiaDebesis View Post
Hi,

How much do you charge for a piece and two pieces?
I ask 100usd for a pair, plus shipment, around 30usd (shipment can vary a bit depending on destination). I can not use PayPal (not present in my country). Payment via MoneyGram payment system.
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Old 22nd November 2019, 07:49 AM   #7
NiaDebesis is offline NiaDebesis
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Anyone that knows what this symbol means?
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Old 23rd November 2019, 03:56 PM   #8
VladimirK is offline VladimirK  Uzbekistan
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Quote:
Originally Posted by NiaDebesis View Post
Anyone that knows what this symbol means?
A symbol means anode ( plate) C symbol means grid
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