Are this tubes usable ?

[kagliostro]

From a Jerrold 900B Sweep Generator

that a fried disassembled

I have some nice tube

12at7 - 12ay7 - 6au6 - 6cw5 - 6922 - 7308

are the 12ay7 - 6922 - 7308 usable for guitar amps ?

someone has link to schematics were this tubes are used ?

and more

I'm very curious about the screen connected to pin number 9 in the 6922 tube 
(between the two triodes)

which is the purpose for that ??

THANKS

Kagliostro

[jjasilli]

http://www.mif.pg.gda.pl/homepages/frank/sheets/030/e/E88CC.pdf

The 6922 is a double triode; there is no screen, only: cathode, grid and plate.  The drawing is deceptive, EDIT:  but the "center tap" (9) on the heaters is not connected to the grid.  The heaters wired are just like a 12a_7 tube.  However I think it only wants a total of 6V not 12V.

[SirElwood]

I'm very curious about the screen connected to pin number 9 in the 6922 tube  
(between the two triodes)

which is the purpose for that ??

It is shield between two triodes. Prevents crosstalk between two triodes (I think). Some russian tubes (6N2P for example) has same kind of shielding. Shield should be connected to ground. Heater wiring is pins 4. and 5. So no center tap like 12A_7 types.

[Rev D]

12ay7 works great as a lower gain preamp tube, its what was used for example in the Fender tweed deluxe as V1. The 12at7 can be used as a tube in the Fender reverb scheme I know my princeton reverb I built uses one.

Regards,

D.

[HotBluePlates]

I have some nice tube

12at7 - 12ay7 - 6au6 - 6cw5 - 6922 - 7308

are the 12ay7 - 6922 - 7308 usable for guitar amps ?

7308 and 6922 are special versions of the 6DJ8/ECC88. You could use the in guitar amps, but they'd probably be more useful in a hi-fi amp. They are often used in cascode circuits, which can use 2 triodes to give the performance and gain of a pentode. But you could just as easily use a pentode and fewer parts.

Hi-fi folks might pay good money for them, depending on brand and construction.

[kagliostro]

Thanks to all

at the moment my abilities aren't adequate to use the two tubes in a cascode self made schematic

but I think to keep it and don't sell

if I want to sell them I think I can do it also into the future

Kagliostro

[RicharD]

The 6922 (6DJ8) is one of my flavorite tubes.  I built a line level preamp & headphone amp that hangs off my PC using 6922's.  Maybe not quite hifi, but at least midfi.

[PRR]

2175V? 

[kagliostro]

Richard told me that the 2175v are a special add on feature of the preamp

to fry the mosquitos flying around giving disturbance    

Hi Richard

Many thanks for the schematic

Kagliostro

[RicharD]

Doh!  My fingers aren't really that fat, although 1 is bleeding at the moment.  Seriously considering DIY stitches.  It's Monday, it's hot, and now I'm bleeding.  Painful way to get the afternoon off.  Gosh I hate doctors.

[DummyLoad]

Doh!  My fingers aren't really that fat, although 1 is bleeding at the moment.  Seriously considering DIY stitches.  It's Monday, it's hot, and now I'm bleeding.  Painful way to get the afternoon off.  Gosh I hate doctors.

i guess you won't be helping me wire up the SC30 tonight?   

bummer 'bout the fanger... :(  hope it heals quick and well. 

[RicharD]

Yeah... I'm out of the game for a few days.  I shoulda gotten stitches but opted for liquid bandage & butterflies.

oops!  Thread hijack.  Don't run your 6922's at 2175V.   

[kagliostro]

OK I'll run it at 175v

hope your finger is better today

Yesterday you told it was a very hot day here it was very cold

I have had to change my shirt with short sleeves with one with long sleeves

is a strange summer

Kagliostro

[PRR]

> It's Monday, it's hot, and now I'm bleeding.

Electrical work is bloody.

I suggest the bacon bandages.



http://www.epartyunlimited.com/bandages.html#top

Actually, paper-towel and duct-tape is more functional than most sticky-strips, if you can tolerate the bulk long enough to stop dripping.

[RicharD]

Napkins from lunch and electrical tape is the typical triage.  Work with what you got right?  I swear by "New Skin Liquid Bandage".

[kagliostro]

Recently I have been able to experience of person the use of paper-towel and duct-tape

I've cut a finger, enough deeply, with a paper sheet

of necessity virtue 

Kagliostro

[Rev D]

Napkins from lunch and electrical tape is the typical triage.  Work with what you got right?  I swear by "New Skin Liquid Bandage".

 Years ago I was a tournament bowler, used to use that stuff to repair the thumb after 10-15 games worked pretty good. Of course the best solution was to get another pro shop drill the ball better which was the ultimate fix but won't have much to do in your case. :D The stuff does work though pretty good. Even the hospitals use something similar to super glue these days.

Regards,

D.