Are those tubes in normal condition ?

Pat_rocks92

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Hello guys i have an issue with a matched pair of tubes i bought,

i bought a (advertising : matched pair of tubes sylvania 6ca7 NOS)

however to my surprise i recieved a rca made in USA tube with the sylvania one.

So the RCA has 2 getters and is labelled made in usa. So if i remember correctly , rca tube factory was bought by sylvania. First issue : it has solder floating or some glass floating inside (could it be the transport ? but they were well packed).


IMG_4256.jpg


The sylvania 6ca7 has a single getter and it has poorly cut plate ends (holders). i saw some pictures of single getter sylvania tubes i seem that the plate ends are polished and not like that :



tube.jpg


is this normal for a sylvania tube ? I mean it looks like it was poorly cut or just burnt due to bad usage.

The tubes seems used and not NOS.

On my reception and refund asked by ebay, the guy instantly refunded me today without the need to give the tubes back... and this makes me feel bad for him...

However if you say that this is normal for a sylvania 6ca7 to have the ends of the plates this poorly trimmed and burnt i'am willing to leave him half of the price.

was this a scam and the guy sent me bad condition tubes ?

Or could it be that transport damaged the rca tube and the sylvania tube was just poorly manufactured ?

Any advices ?

thanks for your help.
 
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Jon Snell

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They all look like 5881s or 6L6s short and stubby. EL34s (6CA7s) have long envelopes.
Your first picture shows a valve that has been used but probably still OK.
The second photo you say 'cut and soldered'. That is not possible. The getters are spot welded in place and probably are a little untidy but not a problem.
The third photo looks like a healthy new 5881 with a single getter.
 

Pat_rocks92

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They all look like 5881s or 6L6s short and stubby. EL34s (6CA7s) have long envelopes.
Your first picture shows a valve that has been used but probably still OK.
The second photo you say 'cut and soldered'. That is not possible. The getters are spot welded in place and probably are a little untidy but not a problem.
The third photo looks like a healthy new 5881 with a single getter.
so the ends of the wire which seem burnt are normal ? one is almost cut in half.

Isn't this sign of overheat or bad usage ?

I didn't dare to use the tubes not knowing if they could damage the amp...

I have been looking for pictures of single getter sylvanias but in those pictures the wires seem polished and not burnt of cut.

if you confirm me this is normal and safe to use then i will pay him back half i spent and send back the rca tube or signal ebay there was a mistake and perhaps transport damage x)...
 
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Pat_rocks92

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"Update" i posted in a forum dedicated to vacuum tubes and they told me to send them back to seller. Apparently they are not in usable condition.
 

rdjones

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Music City, TN
Hello guys i have an issue with a matched pair of tubes i bought,

i bought a (advertising : matched pair of tubes sylvania 6ca7 NOS)

however to my surprise i recieved a rca made in USA tube with the sylvania one.

So the RCA has 2 getters and is labelled made in usa. So if i remember correctly , rca tube factory was bought by sylvania. First issue : it has solder floating or some glass floating inside (could it be the transport ? but they were well packed).


View attachment 1001196

The sylvania 6ca7 has a single getter and it has poorly cut plate ends (holders). i saw some pictures of single getter sylvania tubes i seem that the plate ends are polished and not like that :



View attachment 1001202

is this normal for a sylvania tube ? I mean it looks like it was poorly cut or just burnt due to bad usage.

The tubes seems used and not NOS.

On my reception and refund asked by ebay, the guy instantly refunded me today without the need to give the tubes back... and this makes me feel bad for him...

However if you say that this is normal for a sylvania 6ca7 to have the ends of the plates this poorly trimmed and burnt i'am willing to leave him half of the price.

was this a scam and the guy sent me bad condition tubes ?

Or could it be that transport damaged the rca tube and the sylvania tube was just poorly manufactured ?

Any advices ?

thanks for your help.
The RCA tube manufacturing operation was bought by GE.

RCA never made EL34s or 6CA7s.
EL34s labeled "RCA" were made by Mullard for the most part.
6CA7s labeled "RCA" were made by Sylvania or possibly GE.
The differences in the getters is due to late vs early production.
The sloppy spot welds on the plate support rods is charactistic of Sylvania and should not be cause for concern in itself.

Operating condition aside, it's doubtful that they are "NOS" if they were not supplied in factory cartons.
I don't believe this is an intentional "scam", rather just an opportunistic or optimistic eBay seller.
 

rdjones

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They all look like 5881s or 6L6s short and stubby. EL34s (6CA7s) have long envelopes.
Your first picture shows a valve that has been used but probably still OK.
The second photo you say 'cut and soldered'. That is not possible. The getters are spot welded in place and probably are a little untidy but not a problem.
The third photo looks like a healthy new 5881 with a single getter.
I'm certain that the tubes shown in the OP photos are not 5881s, 6L6s or "EL34s".
They are US made 6CA7 beam power tetrodes, not true pentodes like Mullard's EL34 design.

EL34s and 6CA7s are pin compatible and fully interchangeable, but different construction internally.
In both cases the suppressor grids/plates are brought out to pin 1, not connected internally to the cathode.
 

NTC

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^--- This is correct. 6CA7's have large bottles and look like a bigger 6L6GC. I have always heard they are beam power tubes, but the Tung Sol data sheet refers to them as pentodes. The suppressor grid still has a pin, though that connection could go to the beam forming elements.
 

Wally

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‘Fat bottle’ 6CA7s…Sylvania production. @Pat_rocks92, do you have a tech nearby who has a decent tube tester? It may be that after assuring the tubes are safe in a circuit…which I think they will be, one might find that those are some decent tubes…..or maybe not. If you get them into the circuit, then a Tech can assess their operation and you can hear what they do. I take it that you did not pay huge money for those tubes. Otherwise, the seller would have perhaps had more to say about the deal????
 




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