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Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 397

post #5941 of 10501

I am not a fan of the Chinese, even the JunDui doesn't do it for me. The best Russian is the DR variant but still prefer the Western 2C51s.

post #5942 of 10501
Quote:
Originally Posted by mordy View Post
 

Gibosi, do you have to cross wires inside the octal base to accommodate the 7963 tube? How do you insulate them and or reduce hum?

 

I am quite sure some of the wires would cross, so it will be necessary to insulate them in some fashion. As i lovemusic 2 suggested, a spent ballpoint pen ink tube and some electrical tape might do the trick, or if one has a heat gun, some heat-shrink tubing.

 

The rock grotto posting I referenced above shows the tube mounted into a 9-pin socket saver with heat-shrink tubing.

 

http://rockgrotto.proboards.com/thread/9798/sylvania-7963-best-e88cc-planet?page=1&scrollTo=134293

post #5943 of 10501

I want to try this tube(Sylvania subminiature 7963)but it is CAD $22 plus shipping wow....:eek:

post #5944 of 10501
Quote:
Originally Posted by i luvmusic 2 View Post
 

I want to try this tube(Sylvania subminiature 7963)but it is CAD $22 plus shipping wow....:eek:

 

Yeah, it's pretty crummy. If you check eBay's sold listings, a lot of 5 went for only $19.99, with free shipping in the states, just a few months ago. Now they are going for 5 times that! :(

 

There is currently one listing on eBay for $24, or best offer. My first offer was 3 for $30, and it was refused. My second offer was 2 for $30, and that offer was refused as well. Finally, I offered to buy just one for $20 and was accepted. Shipping in the states is $4, so it appears that for now, $24 is about cheap as we are going to get. However, it just might be possible to find them from sources outside of eBay for less....

 

I figure that there can't be that much demand for these as the wire leads limits them to tinkerers. Perhaps in a few months we will see the prices on eBay go back down.....

post #5945 of 10501

There are plenty of other good wired leadout tubes people may want to try that are more conventional in size like CV4033 (12AT7 / ECC81), CV4034 (12AU7 / ECC82), CV4035 (12AX7 / ECC83), CV4109 (7308 / E188CC), CV4069 (13D3). All of the listed CV numbers are 'premium' examples.

 

Others of note but not relevant here CV4001 (6X4 / EZ90), CV4086 (EF86).

post #5946 of 10501

For the 7963, 6832 and perhaps other sub-miniature "Pencil" double triodes.....

 

Mordy asked for a diagram indicating how to wire the external socket to the Vectors, so I thought I should also post it here:

 

Holding the tube upside down, the gap between lead #1 and lead #8 is a bit wider than the others, just like it is on our 7-pin and 9-pin tubes. And like those tubes, upside down, #1 is on the left and you go around the tube clockwise ending at #8.

 

9 Pin socket                                 Left LD socket                    Right LD socket
 
1 plate triode 2                                                                                   5
2 grid triode   2                                                                                   1
3 heater -- external PS or                                                                     3
4 cathode triode 2                                                                               2
5 cathode triode 1                                    2
6 heater -- external PS or                                                                     4
7 grid triode 1                                          1
8 plate triode 1                                         5

9 not used

post #5947 of 10501
Quote:
Originally Posted by TrollDragon View Post
 

 

That looks pretty badass!!!

 

Anyway here is my LD that I changed tubes on :)

 

 

post #5948 of 10501

Can you guys see any tubes in these pictures that are usable with the littledot or with a power supply. Thanks                                                                                                                                                                                                                                                                                       


Edited by MIKELAP - 4/25/14 at 4:36pm
post #5949 of 10501
Quote:
Originally Posted by MIKELAP View Post
 

Can you guys see any tubes in these pictures that are usable with the littledot or with a power supply. Thanks

 

A quick look...

 

In pic#1, there is an 8FQ7/8CG7 top center

In pic#2, there are a couple of 12Bh7

In pic#3, there are a couple 8FQ7 and a 6CG7/6FQ7

 

So I don't see any treasures, but again, it was just a quick look....

post #5950 of 10501
Quote:
Originally Posted by Androb View Post
 

That looks pretty badass!!!

 

Anyway here is my LD that I changed tubes on :)

 

What were your old tubes?  And what are your new tubes?

post #5951 of 10501
Quote:
Originally Posted by gibosi View Post
 

 

A quick look...

 

In pic#1, there is an 8FQ7/8CG7 top center

In pic#2, there are a couple of 12Bh7

In pic#3, there are a couple 8FQ7 and a 6CG7/6FQ7

 

So I don't see any treasures, but again, it was just a quick look....

Thanks alot gibosi  found around 35 tubes in all in that box nothing spectacular but usable, they belong to my kid brother so he told me ,take what you need he didnt tell me twice lol. Thanks again.

post #5952 of 10501
Quote:
Originally Posted by Androb View Post
 

That looks pretty badass!!!

 

Anyway here is my LD that I changed tubes on :)

 

 

Thanks!

 

Get out of here... teasing us with your Balanced MK VI+ and the Svetlana 6H5C's :tongue_smile:

post #5953 of 10501
Quote:
Originally Posted by TrollDragon View Post

Thanks!

Get out of here... teasing us with your Balanced MK VI+ and the Svetlana 6H5C's tongue_smile.gif
Hehe :P

Gibosi i'm not but I think they are called RCA 6080. They sound a bit congested compared to these tubes!
post #5954 of 10501

I got a Mullard 6SN7GTY today!

 

 

But everyone knows that Mullard NEVER EVER made a 6SN7.... Right? :)

 

And the flip side reveals that this is actually a BRIMAR CV1988 made in the Oldsway factory (FE)

 

 

I believe the date code of XB = February, 1965. But in the next picture, below, 3J5 = Week 3, Month J, Year 5, several months later. Maybe this is the packing date?

 

And I do not know what the number 383 indicates.

 

post #5955 of 10501
Quote:
Originally Posted by gibosi View Post
 

I got a Mullard 6SN7GTY today!

 

But everyone knows that Mullard NEVER EVER made a 6SN7.... Right? :)

 

Right. The print job looks pretty rough.

 

And the flip side reveals that this is actually a BRIMAR CV1988 made in the Oldsway factory (FE)

 

Believe it or not, the STC Oldway site was right here, next to a mansion of the same name:

 

 

I believe the date code of XB = February, 1965. But in the next picture, below, 3J5 = Week 3, Month J, Year 5, several months later. Maybe this is the packing date?

 

X is actually 1966. This is easier to explain: the CV labels were often printed later.

 

And I do not know what the number 383 indicates.

 

It could be a type code. Not mentioned here, though:

 

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