6SJ7 Vs 6Ж8 - Can the russian tube be considered an equivalent tube ?

[Kagliostro]

Within a pair of weeks I go to the biggest Hamfest here in Italy

a friend bring me some tubes from East Europe and I would like to know

if the russian 6Ж8 tube is a good substitute for the 6SJ7 tube

''Èñòîê2''. Ðàäèîëàìïû - ïî÷òîé. Ïàðàìåòðû è õàðàêòåðèñòèêè 6Æ8

http://www.mif.pg.gda.pl/homepages/frank/sheets/093/6/6SJ7.pdf

( I'm still not able to read correctly tube datasheets 😱 )

Many Thanks

K

 

[MrCurwen]

Looking at the curves: yes. The max g2 voltage rating is different, but russian ratings are more of suggestions than actual ratings. =)

 

[elektroj]

Yes. Russian 6zh7 is a copy of 6SJ7 made by RCA.

 

[Kagliostro]

Thanks

I was thinking 6zh7 is a 6J7 not a 6J8

6J7 has a top cap

6J8 didn't has a top cap

but now I'm confused

😕

K

 

[Kagliostro]

WOW !!

I think I solved the mistery 😀 😀

there are two 6J8 tubes

one is 6J8 the other is 6Ж8

as known J = Ж

but one, the 6J8 tube is a triode / pentagrid tube

the 6Ж8 is a pentode

K

 

[Soundhappy]

I would like to know if the russian 6Ж8 tube is a good substitute for the 6SJ7 tube

@ Kagliostro

From Francis Ibre book " Audio Tubes " Elektor |Publitronic

Yes 6SJ7 = 6Ж8 = 6SH8

Best regards

 

[Kagliostro]

Thanks

but 6SJ7 is slightly different from 6SH7

6SJ7

An externally hosted image should be here but it was not working when we last tested it.

6SH7

An externally hosted image should be here but it was not working when we last tested it.

and I'm not able to find info about 6SH8 you mention

only 6HS8, but is s different tube, a twin pentode with G1 - G2 and cathode in common

6HS8

K

 

[kevinkr]

Cyrillic has 31 characters IIRC as opposed to 26 in the English alphabet and as a result there are several analogs used for the Ж character including "J" "ZH" and perhaps "SH" I generally use the Russian character when ambiguity exists or most commonly the J.

There are also a number of Russian tubes for which no exact equivalent exists. I'm a big fan of a good number of Russian types.

The vademecum found at Frank's here: electron Tube Data sheets - Search will frequently list equivalents and near equivalents if you check the box when you do a datasheet search.

 

[Soundhappy]

I'm not able to find info about 6SH8 you mention....

After book cyrylic Ж = SH in latin characters

Best regards

 

[Kagliostro]

OK, I'm not a good connoisseur about cyrillic characters

I use this correspondence table that is on Duncan's tube search

TDSL Cyrillic characters

Many thanks for the info

K

 

[crispycircuit]

I believe a 6au6 is the miniature version of the 6SJ7....

 

[Kagliostro]

Someone, some time ago, told me that 6au6 corresponds to the 6SH7

---

BTW, someone told me that the 6J7 is comparable to the 5879

K

 

[artosalo]

I would just compare the data of the tubes under comparison rather that search what someone has someday said.
Otherwice you are in the endless speculation.

Datas can be search from here: electron Tube Data sheets - Search

 

[rongon]

I believe a 6au6 is the miniature version of the 6SJ7....

Just to clear things up, if only a little:

6SJ7 triode strapped has mu of 19
6AU6 triode strapped has mu of 36

They're definitely different.

--

 

[Kagliostro]

Have you compared the data on the datasheet ?

They seems establish that those tubes are very close each other

K

 

[rongon]

Yes, of course, I got that information from the data sheets (from Frank Philipse's site).

From the data sheets, it looks like 6AU6 is indeed closer to 6SH7 than it is to 6SJ7.

6SJ7 triode mu = 19
6SH7 triode mu = ca. 35 (estimated from triode curves on datasheet)
6AU6 triode mu = 36

--
6SH7 data sheet - http://www.r-type.org/pdfs/6sh7.pdf

 

[Kagliostro]

Ah, OK, I misunderstand you

I was thinking you were talking about 6SH7 & 6AU6 not 6SJ7 & 6AU6

I apologize for the mistake

K