Add group to favorites
Back to post list
Send new message to group Search:
Post Subject:
6L6GC's with large silver spot
6L6GC's with large silver spot
Just pulled my tubes out to have a look at them, and noticed the
powertubes each have a large silver spot on the glass case about the
size of a quarter... last time i pulled the tubes out (when i first got
the amp) i did not notice these spots... (not sure how new the tubes are
now or when i got it).
Are these spots normal? they are about midway up one side.
Marshall JTM30 & 6l6gc rca blackplates
Just pulled my tubes out to have a look at them, and noticed the
powertubes each have a large silver spot on the glass case about the
size of a quarter... last time i pulled the tubes out (when i first got
the amp) i did not notice these spots... (not sure how new the tubes are
now or when i got it).
Are these spots normal? they are about midway up one side.
Marshall JTM30 & 6l6gc rca blackplates
Re: 6L6GC's with large silver spot
Picasso wrote:
> Just pulled my tubes out to have a look at them, and noticed the
> powertubes each have a large silver spot on the glass case about the
> size of a quarter... last time i pulled the tubes out (when i first got
> the amp) i did not notice these spots... (not sure how new the tubes are
> now or when i got it).
>
> Are these spots normal? they are about midway up one side.
>
> Marshall JTM30 & 6l6gc rca blackplates
RCA blackplates?
Sorry, those are totally fried. Please send them to
NBS Electronics, 230 South Broadway, Denver,
CO 80209-1510 for proper disposal. ;-)
Actually, that spot is called the "getter." It's a
compound that binds up loose gas molecules
to keep the vacuum in the tube pristine. In fact,
when those spots start to turn a brownish-pink
or whitish color, it means that the tubes are
nearing the end of their useful lifetime. The
fact that yours are nice and shiny means you
have nothing to worry about. They're great tubes -
enjoy 'em.
Lord Valve
BaaaaarrrAAAACCCKKK!!! <Safety!>
Picasso wrote:
> Just pulled my tubes out to have a look at them, and noticed the
> powertubes each have a large silver spot on the glass case about the
> size of a quarter... last time i pulled the tubes out (when i first got
> the amp) i did not notice these spots... (not sure how new the tubes are
> now or when i got it).
>
> Are these spots normal? they are about midway up one side.
>
> Marshall JTM30 & 6l6gc rca blackplates
RCA blackplates?
Sorry, those are totally fried. Please send them to
NBS Electronics, 230 South Broadway, Denver,
CO 80209-1510 for proper disposal. ;-)
Actually, that spot is called the "getter." It's a
compound that binds up loose gas molecules
to keep the vacuum in the tube pristine. In fact,
when those spots start to turn a brownish-pink
or whitish color, it means that the tubes are
nearing the end of their useful lifetime. The
fact that yours are nice and shiny means you
have nothing to worry about. They're great tubes -
enjoy 'em.
Lord Valve
BaaaaarrrAAAACCCKKK!!! <Safety!>
Re: 6L6GC's with large silver spot
Picasso wrote:
> Just pulled my tubes out to have a look at them, and noticed the
> powertubes each have a large silver spot on the glass case about the
> size of a quarter... last time i pulled the tubes out (when i first got
> the amp) i did not notice these spots... (not sure how new the tubes are
> now or when i got it).
>
> Are these spots normal? they are about midway up one side.
>
> Marshall JTM30 & 6l6gc rca blackplates
**IMPORTANT INFORMATION ABOUT THE GETTER**
(information taken from Vacuum Tube Valley magazine; a reply by Eric
Barbour)/ **IMPORTANT INFORMATION ABOUT THE GETTER**
(information taken from Vacuum Tube Valley magazine; a reply by Eric
Barbour) - See Tube world Site.
The "getter flashing" absorbs free oxygen, nitrogen, carbon dioxide,
carbon monoxide and hydrogen from the tube whether the tube is used or
not. You can be certain the vacuum is bad "ONLY" if the flashing turns
chalky white all over. If it is silver, black, rainbow-colored, or even
totally gone, the tube might still work fine. In fact, a "BLACK" getter
is MORE effective than a "SHINY" getter at absorbing gas.
Here's a quote taken from GETTER MATERIALS FOR ELECTRON TUBES by Werner
Espe: "If the getter is vaporized very slowly, the first barium atoms
evaporated will absorb the gas present so that the remaining getter is
deposited in a very high vacuum, exhibiting a "shiny" mirror. If
flashing is done very rapidly, however, the getter deposits in a rather
high vapor pressure, and the getter mirror will be discolored
(rainbow-like) due to the dispersion of the barium. If vaporization is
carried out in the inert atmosphere of a rare gas, the condensed deposit
will be "black", resulting in a "dispersal" getter. This condition does
not mean that the getter is contaminated, but merely that the deposit is
finely divided and therefore absorbs light. Such deposits exhibit "HIGH"
efficiency than the bright deposits: i.e. DARKER is better.
Let me make a blanket statement to adequately cover the the subject of
tube viability: The ONLY way to accurately determine the health of a
vacuum tube is to test it ELECTRICALLY. PERIOD. Anyone who discards a
tube because its getter flashing is slightly "discolored" is making a
sad mistake."
Picasso wrote:
> Just pulled my tubes out to have a look at them, and noticed the
> powertubes each have a large silver spot on the glass case about the
> size of a quarter... last time i pulled the tubes out (when i first got
> the amp) i did not notice these spots... (not sure how new the tubes are
> now or when i got it).
>
> Are these spots normal? they are about midway up one side.
>
> Marshall JTM30 & 6l6gc rca blackplates
**IMPORTANT INFORMATION ABOUT THE GETTER**
(information taken from Vacuum Tube Valley magazine; a reply by Eric
Barbour)/ **IMPORTANT INFORMATION ABOUT THE GETTER**
(information taken from Vacuum Tube Valley magazine; a reply by Eric
Barbour) - See Tube world Site.
The "getter flashing" absorbs free oxygen, nitrogen, carbon dioxide,
carbon monoxide and hydrogen from the tube whether the tube is used or
not. You can be certain the vacuum is bad "ONLY" if the flashing turns
chalky white all over. If it is silver, black, rainbow-colored, or even
totally gone, the tube might still work fine. In fact, a "BLACK" getter
is MORE effective than a "SHINY" getter at absorbing gas.
Here's a quote taken from GETTER MATERIALS FOR ELECTRON TUBES by Werner
Espe: "If the getter is vaporized very slowly, the first barium atoms
evaporated will absorb the gas present so that the remaining getter is
deposited in a very high vacuum, exhibiting a "shiny" mirror. If
flashing is done very rapidly, however, the getter deposits in a rather
high vapor pressure, and the getter mirror will be discolored
(rainbow-like) due to the dispersion of the barium. If vaporization is
carried out in the inert atmosphere of a rare gas, the condensed deposit
will be "black", resulting in a "dispersal" getter. This condition does
not mean that the getter is contaminated, but merely that the deposit is
finely divided and therefore absorbs light. Such deposits exhibit "HIGH"
efficiency than the bright deposits: i.e. DARKER is better.
Let me make a blanket statement to adequately cover the the subject of
tube viability: The ONLY way to accurately determine the health of a
vacuum tube is to test it ELECTRICALLY. PERIOD. Anyone who discards a
tube because its getter flashing is slightly "discolored" is making a
sad mistake."
Re: 6L6GC's with large silver spot
Picasso wrote:
> Just pulled my tubes out to have a look at them, and noticed the
> powertubes each have a large silver spot on the glass case about the
> size of a quarter... last time i pulled the tubes out (when i first got
> the amp) i did not notice these spots... (not sure how new the tubes are
> now or when i got it).
>
> Are these spots normal?
Yes. It's called 'getter' a mixture of highly reactive metals intended to
'absorb' by oxidation any gas left in the tube after 'evacuation' ( putting
the vacuum in - LOL ) at the factory.
Graham
Picasso wrote:
> Just pulled my tubes out to have a look at them, and noticed the
> powertubes each have a large silver spot on the glass case about the
> size of a quarter... last time i pulled the tubes out (when i first got
> the amp) i did not notice these spots... (not sure how new the tubes are
> now or when i got it).
>
> Are these spots normal?
Yes. It's called 'getter' a mixture of highly reactive metals intended to
'absorb' by oxidation any gas left in the tube after 'evacuation' ( putting
the vacuum in - LOL ) at the factory.
Graham
Re: 6L6GC's with large silver spot
Eeyore wrote:
>
> Picasso wrote:
>
>> Just pulled my tubes out to have a look at them, and noticed the
>> powertubes each have a large silver spot on the glass case about the
>> size of a quarter... last time i pulled the tubes out (when i first got
>> the amp) i did not notice these spots... (not sure how new the tubes are
>> now or when i got it).
>>
>> Are these spots normal?
>
> Yes. It's called 'getter' a mixture of highly reactive metals intended to
> 'absorb' by oxidation any gas left in the tube after 'evacuation' ( putting
> the vacuum in - LOL ) at the factory.
>
> Graham
>
...You expected more from our GO Getter*? :-) mvm
* Go Gutter
Eeyore wrote:
>
> Picasso wrote:
>
>> Just pulled my tubes out to have a look at them, and noticed the
>> powertubes each have a large silver spot on the glass case about the
>> size of a quarter... last time i pulled the tubes out (when i first got
>> the amp) i did not notice these spots... (not sure how new the tubes are
>> now or when i got it).
>>
>> Are these spots normal?
>
> Yes. It's called 'getter' a mixture of highly reactive metals intended to
> 'absorb' by oxidation any gas left in the tube after 'evacuation' ( putting
> the vacuum in - LOL ) at the factory.
>
> Graham
>
...You expected more from our GO Getter*? :-) mvm
* Go Gutter
