Re: {Collins} 811A Blues



Joe,

Do not feel that you are alone. The EXACT same thing happened to me. White powder & all. I knew I was beyond the "30 Day" warranty (6 months old) so kind of knew it was going to be a fruitless battle and just threw them in the trash and replaced with NOS RCA 811A tubes!!!

`Word to the wish gentlemen.

73, Tom W1ALZ


On 5/25/2015 4:12 PM, Joe wrote:
Guys,

Back about 18 months ago, I acquired a RE 30L1 but the guy shipped it with
the tubes in. There was a pair of Cetron's and a pair of nice RCA's. As it
would be one on each pair came loose and broke. With help from the seller I
purchased 3 brand new Cetrons from Surplus Sales of Nebraska. Now I'm pretty
experienced engineer who held a general class ticket in 1963 at the age of
13 so I didn't just fall off the turnip truck. Anyway after going through
the amp and installing the tubes she came up fine on all bands into my dummy
load. The amp sat for about a year and was never put on the air so I had no
more than 30 minutes on the tubes. Then I decided to put the amp into
service and prior to powering up I noticed white crystals around the base
and plate caps on all three tubes purchased from Surplus Sales. The
remaining Cetron from the original purchase seems fine, no white crystals at
all. I removed the top two 811s and right away the plate cap was loose. I
took pictures of both the tubes I removed and the remaining ones in the
bottom and sent a nice email to Surplus Sales explaining what had happened,
here is his reply:

JOE,

THE WARRANTY IS 30 DAYS. LOOKS LIKE WE HAVE ABOUT 2 YEARS HERE. THE TUBES
ARE NOT COVERED FOR REPLACEMENT.

THERE WAS NOT A "BAD LOT OF TUBES" ELECTRICALLY. EVERY SINGLE 811A WE HAVE
SOLD HAS PASSED AN RF TEST BEFORE SHIPPING. WHAT WE DID FIND IS THAT IF GUYS
GOT A LITTLE ROUGH WITH THE INSTALLATION, THE CAPS COULD COME LOOSE. THE
WHITE CRYSTALS ARE AN AFTER EFFECT FROM THE GLASS CEMENT THAT WAS USED TO
REINFORCE THE CAPS AND BASES. IT DOESN'T HURT ANYTHING. IF YOU HAVE A LOOSE
PLATE CAP THAT MEANS YOU EVEN TORQUED IT ENOUGH TO BREAK THE BOND ON THE NEW
CEMENT.

BOB  WD0FDE


I have since removed the other two tubes and not only are the caps loose but
so are the bases. I want to know if this guy is being honest with me because
I can't see how this could of happened, I know my handling was not the cause
of this. I happen to own another 30L1 with RCA tubes and have never seen
anything like this.

Any input would be appreciated

Joe KV4PN





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