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Tube question - OzRadio - 08-11-2006

I'm pricing a replacement tube - 25L6. Radio Daze lists it at 8.50 but has a 25L6GT/25W6 for 4.00. What is the difference in price? What does the GT indicate?
Thanks,
Ryan


Re: Tube question - n9vu - 08-11-2006

OzRadio Wrote:I'm pricing a replacement tube - 25L6. Radio Daze lists it at 8.50 but has a 25L6GT/25W6 for 4.00. What is the difference in price? What does the GT indicate?
Thanks,
Ryan

GT stands for Glass Tube. Some tubes came in a metal casing. Only those that did were dignified by GT.

Pricing varies from place to place. I find that the more pricey tubes like the one you're looking at, offer either NOS (new old stock), or used but guaranteed (?) good. Either way, most companies offer you a guarantee you will not receive a dud, and you'll have a tube with good life. If you're in the midewest, look up N9TEW radio tube sales. He's never done me wrong, prices are reasonable, and I've bought alot of tubes from him in the past.


GB


Tube Question - planigan - 08-18-2006

Ryan, there is another difference between the G and GT tubes. Most of the newer GT tubes have metal base and pin No. 1 is grounded. On some sets the pin No. 1 terminal may be used by the manufacturer as a common terminal for other circuits (other than the tube involved). If you use the GT tube you could ground out the circuit. This info was posted on Nostalgia Air, references, articles, Using GT tubes as substitutes for non-GT tubes. I also beleive the GT tube is a newer design of the G tube. Both class but the GT had the metal as opposed to the bakelyte/phenol/plastic base. I don't know what the designation was for the metal tubes but they where used do away with the metal tube shields. PL