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Svetlana MVSZ ---> cheat??

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Hi there...........I've a sneaking suspicion that all's isn't going well over there in Russia....Someone may know better than me, but I suspect 6550C manufacturing is waning ? My own supplier is having difficulty getting my quanitiy.....

I've also tried direct ordering but the danger of too many old websites which haven't been updated...the US is also to blame for this...If youv'e ordered by CC, keep an eye on that statement.

Big companies are notorious for lazy email replies....

richj
 
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Probably better to deal with PM Components, the people who import and distribute Svetlana (winged C) tubes in Europe and the USA.

I looked at that website and it is hard to know whether it is even the real Svetlana.

The poor English, and unprofessional feel of the website make me suspicious. Buying Russian tubes directly might be safer through someone like www.tubes.ru (if they are still around - I was unable to connect to their site today.)

If you paid by credit card or paypal and have not received your tubes I would file a complaint immediately.

Note that the Svetlana brand ubes sold by New Sensor in NYC (SED box) are not made or designed by Svetlana in St. Petersburg..

I don't know what is going on with Svetlana, but current production Russian made 6550 are readily available here.

Kevin
 
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I just checked their site and it is indeed up, just the usual vagaries of internet hosting and dns lookup serving. If I had the ip address it would probably have been directly accessible.

Anyway the point I was trying to make is that it is not clear to me whether that Svetlana MVSZ website is totally legit - it wouldn't be the first time something like that happened.. Better to buy from someone you really know.

It is my understanding (possibly erroneous) that Technical Center Navigator aka www.tubes.ru is descended from the state controlled agency that handled tube sales to the west back in the late days of the Soviet Union. They have a lot of different types available at reasonable prices in quantity.

Best place to get Svetlana tubes for the average guy is probably from PM Components Group or one of their authorized distributors.

Kevin
 
PLEASE, russian speakers needed !!

Hi all,

Today, I have get an email from Svetlana MVSZ.

They say that send tubes past May 19th and they attach a picture of post office... but... I don't speak in russian, and I don't understand a sole word.

Please, if you can read russian, can you translate these words that I attach?



specially, I am very interesting in TRACKING NUMBER if it exists)


Thanks in advance.
 

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Hi,

here the relevant information:
it' s a receipt for an internation air-mail parcel, 500 gr. weight, sent to Madrid, Spain.
It was sent on 18th May, 2005, 6:18 PM.
The name of the clerk at the Russian post office is E. V. Vedernykova.
The receipt number is: 94927 (I guess you can refer to this shipment number if you want to place any complaint).

Cheers,

Bruno

EDIT: the complete tracking no. should be 190000 (62) 94927 7.
Actually, 190000 is the Zip code of the town in Russia where the shipment has been made.
 
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Note that some winged C tubes are sold under the PM brand, these include the 6550 and KT88.. Prices nothing to write home about though.

Triode Electronics might be able to help source these tubes if you are looking for them.. The other option is to buy them from a reputable overseas vendor..

IMHO the JJ product is about as good in my experience, and the EH EL34 sounds better in many amps than either..

Kevin
 
I have get the tubes, but matching is very bad

Carondimonio said:
Hi,

here the relevant information:
it' s a receipt for an internation air-mail parcel, 500 gr. weight, sent to Madrid, Spain.
It was sent on 18th May, 2005, 6:18 PM.
The name of the clerk at the Russian post office is E. V. Vedernykova.
The receipt number is: 94927 (I guess you can refer to this shipment number if you want to place any complaint).

Cheers,

Bruno

EDIT: the complete tracking no. should be 190000 (62) 94927 7.
Actually, 190000 is the Zip code of the town in Russia where the shipment has been made.

Hi Carondimonio,

Thanks for your valuable help.
I have founded the parcel and yes, you are right, these numbers are the correct Tracking Number.

It has past three months since I buy the tubes at Svetlana... a large lead time.

On the other hand, I have measured bias points of SV-300B (they are sold as matched pairs) and I must say that matching is non existent in this pair I have received.

Bellow are numbers I have found in measures:

Va = 300V
Vg = -61V
Ia1 = 45 mA
Ia2 = 67 mA
gm1 = 5,0 mA/V
gm2 = 5,8 mA/V

:dead: wow !! there is a 48% of mismatching in DC plate current and a 16% in gm!!
 
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Hi,
I didn't realize that you had bought the 300B. Five out of ten I bought failed due to intermittent filament to grid shorts, and of the ones that remain none are now closely matched! All came from SED or directly from Svetlana in St. Petersburg.. IMHO they sounded good when new, deteriorated relatively quickly and are only slightly better than the cheaper chinese tubes. I had both type II and the later type III which was supposed to fix the shorting issue but didn't. I have had far better luck with JJ.. IMHO the tubes you got are probably old ones, to my knowledge they are not even made anymore, and it is not hard to see why with the problems. It is not even so much workmanship related as design related, the assembly on all of mine was well executed, but the filament geometry to the grid was not right due to the length of the filament support springs.

I use mine only for initial testing and hesitate to sell even the good ones I have left on eBay, although none failed in the catastrophic manner of some chinese made ones. (VA and Shuguang both)

Sorry to hear of your misfortune..

Kevin
 
Hi there..........the same goes for poor glass quality....as an end user of alot of tubes I've never seen so much poor glass quality with bubbles and sleeks in tubes from other vendors. (sleeks gradually leak air)......I send em' back.
The only exception was an order of Svet 6550C's the glass was completely flawless. I'm beginning to like these tubes.

My forefathers would have never accepted KT88's with cosmetic problems......nor would anyone accept a new car with scratches.....would anyone ?

Caveat emptor.... so much these days..... it's only the financing that counts.....who cares about the rest ?

richj
 
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