Please give your contribute - add a tube to this list

[kagliostro]

MANY THANKS DummyLoad & PRR

so 6005 / 6005W is another tube that can be add to the list of usable tubes

about 5687 i'll use it if I need but don't look to have more

about the amp it isn't in perfect conditions, rats has nibbled some part of the PT outcoming wires

so It must be serviced before to turn on

Kagliostro

[kagliostro]

My mind isn't the same of some years ago, sometime I've little remembering confusions

So, by mistake, thinking to buy a pair of ef40 tubes, I got a pair of ef42 tubes

http://www.r-type.org/pdfs/ef40.pdf

http://www.r-type.org/pdfs/ef42.pdf

are this tubes usable in audio amps ?

Thanks

Kagliostro

[kagliostro]

A new tube to be added to the usable list ??

12fq7

http://www.tubebooks.org/tubedata/HB-3/Receiving_Tubes_Part_2/12FQ7.PDF
http://www.tubebooks.org/tubedata/HB-3/Receiving_Tubes_Part_2/6FQ7.PDF

it is a pin to pin swap with 12a*7 tubes

and if the info I've are correct has a bit more gain than 12au7, however less than 12ax7

what do you think ?

Kagliostro

[DummyLoad]

6cg7/6fq7/12fq7 are 6SN7 with down-rating of plate voltage and plate dissipation.

http://www.triodeel.com/rca_c13.gif

i've been fooling around with sub-miniatures lately - 6111 - 6112 - 5639, etc. i use a mill-max 8 pin DIP wire-wrap socket - kind of a rig, but it works.

--DL

[sluckey]

Kagliostro, did you see the pic of the QK653 I posted in the 'Other Topics' forum? It's been recommended for a nice high power Champ.   

[kagliostro]

@ DummyLoad

I've seen some of those little tubes just yesterday, here

http://www.ebay.it/itm/5977-Sylvania-triodo-amplificatrice-lotto-n-10-pezzi-/220937164704?pt=Attrezzature_e_strumentazione&hash=item3370e197a0

http://www.ebay.it/itm/5719-Sylvania-triodo-amplificatrice-lotto-n-10-pezzi-/220937166363?pt=Attrezzature_e_strumentazione&hash=item3370e19e1b

http://www.ebay.it/itm/5896-Sylvania-doppio-diodo-lotto-n-10-pezzi-/220937168047?pt=Attrezzature_e_strumentazione&hash=item3370e1a4af

If I remember well the "Super Champ" preamp use one of those micro tubes

@ Sluckey

QK653

What a tube ........!

---

which is the gain factor for the 12fq7 ?

http://thetubestore.com/gainfactor.html

Kagliostro

[kagliostro]

I've just discovered that with an adaptor a 5755 can be used instead of a 12ax7

http://minkara.carview.co.jp/userid/192998/car/80313/2974631/photo.aspx

only all the text is in japanese and I'm not able to understand well also with the use of a translator

the question is:

compared with 12ax7 which tube is a 5755, a less or a same gain tube ?
(as you know I and datasheet we aren't too friendly)

Kagliostro

[HotBluePlates]

The 5755 seems largely similar to the 5751.

Compared to the 12AX7, it has somewhat less gain; mu is 70 instead of 100.

Compared to the 5751, it has same mu, higher heater current and high Gm. I am betting the higher Gm is largely due to the higher heater current, with most else being similar to the 5751.

[DummyLoad]

much higher plate resistance than a 5751 and an lower anode volt rating. ~140k rp. need to work around that - typical ~1M loads will load the poor little 5755 down.

HBP, i have around 10 sleeves of them and i acquired them for next to nothing - message me if you'd like to give a pair a spin around the block.

best results i've been able to sim so far with what seems like decent headroom, etc., is:

250V = B+
Ra = 100K,
Rk = 2K2,
Ibias ~ 0.66mA,
Vgk ~-1.5V
AV ~28,
Vo ~ 60V pk,
Zo ~55K.

datasheets say tube was designed for low noise instrumentation amp. applications.

seem to have gain similar (a bit less) to that of the 12AY7 with fenderish component values and B+.

--DL

[kagliostro]

Many Thanks HotBluePlates & DummyLoad

Kagliostro

[66merc]

I think we have overlooked the obvious 12v6.  Available for about five bucks if you look hard enough.  I'm building a simple self-split push-pull using two of these.  5F1 simple front end.  Edcor PT with 180v HT and 12.6v heater secondary.  Cheap, but decent aluminum chassis from ebay.  The Edcor OT is 10k, 10W---I hope it's beefy enough.



66merc

[DummyLoad]

5992

rare. expensive. bendix red-bank. high-rel 6V6

cool and very rugged looking tube.

--DL

[kagliostro]

12V6 & 5992

OK two other tubes in the list 

thanks

Kagliostro

[DummyLoad]

If I remember well the "Super Champ" preamp use one of those micro tubes.

it does - the 6948. very nice sounding tube with similar characteristics of the 5751.

much thanks for the ebay.it links. i contacted the seller to see if he'd ship to USA.

http://www.ebay.it/itm/5719-Sylvania-triodo-amplificatrice-lotto-n-10-pezzi-/220937166363?pt=Attrezzature_e_strumentazione&hash=item3370e19e1b#ht_520wt_1163

we'll see what they say.

grazie! 

--DL

[kagliostro]

Yes, they do

Spedizione in: America, Europa, Asia, Australia

only you must ask for expedition price

Ciao

Kagliostro

[kagliostro]

Would say that things are not to be despised, on the contrary

http://jjs.at/electronic/class_a_subminiature.html



http://jjs.at/electronic/class_ab_subminiature.html



AB amp samples

Clean (347 kB) - gain at 9 o'clock, strat neck pickup
http://jjs.at/electronic/class_ab_subminiature_clean.mp3

Distortion (652 kB) - gain at 12 o'clock, strat bridge pickup
http://jjs.at/electronic/class_ab_subminiature_half.mp3

Distortion (839 kB) - full gain, strat bridge pickup
http://jjs.at/electronic/class_ab_subminiature_full.mp3

Were it not for the advent of transistors, today  mini tubes would be in all HiFi equipment

The mini tubes we can find were planned to be used in military equipment, so they have a high quality that many of the other tubes haven't

About 6AR11 unfortunately I've a pair but didn't result that they are usable tubes for guitar amp purpose

from the previous page of this tread

any suggestion of use for the 6ar11 compactron tube ?

twin semi-remote cut-off pentode w/ high slope. data-book says it's used as IF amp in TVs.

seems to be of no use. maybe a small P-P amp @ 2.5-3W? don't know if remote cut-off tubes will work in power amp - i'll deffer to the experts.

---

I did try that with a 6AR11 - I can't remember the circuit values, but the output power was minimal, and the crossover distortion horrendous. I too will defer to the experts.  

Obviously it could be triode wired as a small signal valve, but there are plenty of twin triodes which would do a better job.

Why build a mini bassman, or tiny twin.

Why many people love things like Ipod  

Kagliostro

[Tiny_Daddy]

Let's not forget 829B, a matched power pentode pair in every bottle. I run a pair in the house stereo amp.
Similar to QQV07-40. This tube has been called the most popular VHF tube of all time.

[kagliostro]

Hi Tiny Daddy

This reminds you of something ? 

 



Kagliostro

[Tiny_Daddy]

Yeah, something... oh, that's my stereo amp! Been running it over 10 years now.

[kagliostro]

One other tube which purpose was to be used as filter in PS

the 6216



http://www.wps.com/archives/tube-datasheets/Datasheets/CBS-PA-5/4.JPG

http://www.wps.com/archives/tube-datasheets/Datasheets/CBS-Bulletin-E-290S/8.JPG

http://www.wps.com/archives/tube-datasheets/Datasheets/Raytheon-SP-7357-8-61-20M/8.JPG

http://www.wps.com/archives/tube-datasheets/Datasheets/Raytheon-SP-7357-8-61-20M/9.JPG

someone knows if it was used  only for military purpose or also in audio equipments ?

Kagliostro

[DummyLoad]

8077/7054 - 5W power pentode cool little tube. 12V heater. g2 is frail.  

http://tubedata.milbert.com/sheets/079/8/8077.pdf

edit: 

added 7061 - interesting lower voltage tube. 10kRa-a PP @ 200V B+ seems workable for about 6W or so. can be had for 5-10 buks.

http://tubedata.milbert.com/sheets/049/7/7061.pdf

--DL

[kagliostro]

Interesting tubes

Thanks DL

Kagliostro

[kagliostro]

One more tube

6BE6 an heptode

http://www.retrovox.com.au/6BE6audi.pdf

http://www.r-type.org/exhib/aaa0011.htm

it was also used by Playmaster in guitar amps as mixer

Kagliostro

[markusv]

Kagliostro

Are you building a list that you will share?

Here's my contribution:
6N2P
Its a Russian equivalent to 12ax7 and if you hurry- it is still cheap on eBay
Just a simple heater re- wire

Markus V

[kagliostro]

Are you building a list that you will share?

That is my intention

Ciao

Kagliostro

[PRR]

> used by Playmaster in guitar amps as mixer

As a variable-gain amplifier to do tremolo.

(It really does work the same as the RF+LO modulator in a superhetrodyne radio, which IS called a "mixer", but it isn't linear mixing.)

[kagliostro]

Hi PRR

Thanks for your clarification

Can you give a bit further explanation or a link for documentation about ?

As far as I can understand the signal goes to pin #1, the oscillator signal goes to pin #7 (of the 6BE6), the effect is that the signal present on pin #7 change the "gain" of the tube and so there is an AM modulation of the signal present on pin #1 when taken at the plate

I know, my knowledge is poor and my explanation is bad, but this is what I can understand from the circuit (and that may be wrong)

I've never seen other amps using this method, do you think it was advantageous or not ?

Thanks

Kagliostro

[sluckey]

5814

[DummyLoad]

2C52

[kagliostro]

Hi Sluckey & Dummy Load

Many Thanks for adding tubes to the list

Please, about your last two adds (5814 - 2C52), can you briefly indicate which will be a possible use for those tubes ?

Today I recovered a PT from a Sommerkamp FT277 and also I got a 12BY7-A (without the adequate glasses I've read it as a 12BH7), does someone knows if for our purpose (guitar amp & related things) this pentode is usable ?

http://www.r-type.org/pdfs/12by7a.pdf

Kagliostro

[DummyLoad]

2C52 is a 12AX7 in octal envelope with 12.6V ONLY filament and 6SL7 pin-out.

--DL

[kagliostro]

2C52 is a 12AX7 in octal envelope with 12.6V ONLY filament and 6SL7 pin-out.

Thanks DL

that is an useful info ........ and tube

Kagliostro

[kagliostro]

From other theads we can add to the list

6x4 and 6x5 rectifiers for small amps (4W / 5W)

6j5 = 1/2 6sn7

6sq7 = 1/2 12ax7

---

6at6 was present in a previous post but unspecified, it is 1/2 5751

K

[kagliostro]

Also this is a good tube to be added to the list

7c5 = 6v6 but with loctal base

K

[DummyLoad]

6F8G - granddad of 12AU7. cool tube - has a grid cap. :-)

--DL

[kagliostro]

Quote from DummyLoad in one other tread

should anyone else have interest in fiddling with 7-pin valves, the 6AB4 is 1/2 of 12AT7, the 6AT6 is 1/2 of 5751, and the 6C4 is 1/2 of 12AU7. there are others but those aforementioned are common still and available at reasonable cost; for time being.... :-\

So as to have also this useful info easily to be find I put it on this tread

6AB4 = 1/2 12AT7

6AT6 = 1/2 5751

6C4   = 1/2 12AU7

K

[kagliostro]

Periodic update of the tread with usable tubes

someone was also previously present in the tread

but here there are reported OT spec & cathode resistor spec

Quote from DummyLoad in one other tread

6AM5 - 4.0W p-p; 250V B+; 24K load; Rk 600R @ 3W
6AR5 - 6.8W p-p; 250V B+; 15K load; Rk 240R @ 3W
6AS5 - 4.4W p-p; 150V B+; 9K load; Rk 1.2K @ 2W
6BF5 - 3.8W p-p; 110V B+; 5K load; Rk 68R @ 2W
6BK5 - 7.0W p-p; 250V B+; 13K load; Rk 68R @ 2W
6CU5 - 4.6W p-p; 120V B+; 5K load; Rk 75R @ 2W
6DS5 - 5.6W p-p; 200V B+; 12K load; Rk 91R @ 2W
6HG5 - 9.0W p-p; 250V B+; 10K load; RK 120R @ 3W  <<-- my favorite.

none of the above exceed the the 60mA 1/2 primary rating at full power. the 6HG5 pushes 9W but may do OK but may have weak lo-freq. repro.
considering the hammond has a spec of 8W @ 100Hz. lo-freq down to 50Hz @ 4W seem doable, 70Hz is what most guitar iron is rated at, and likely have a better response overall running 4-6W . the 6AS5 plan seems to be the easiest to implement - 120V PT will get you up around 160V B+ - close enough - run OT @ 10K load - again, close enough.

K

[kagliostro]

Update

Quote from DummyLoad in one other tread (Thanks Pete)

6J7 is closer electrically to 5879 than 6SJ7.

6SJ7 and EF86 are close electrically.

6SH7 and 6AU6 are electrically same.

6J7/6SJ7/6SH7 are all octal except 6J7 has grid cap. i like 6J7, followed close by 6SJ7.

K

[kagliostro]

This seems one other tube that can be add to the list

the E130L (Power Pentode)

http://www.mif.pg.gda.pl/homepages/frank/sheets/009/e/E130L.pdf

Class AB, 2 tubes in PP = Va 300v | Vg2 150v | Vg1 -17v | Raa 1.6k = 60W



what is uncertain is whether it is economically convenient to use it, prices are very different from one seller to one other 

http://tubedepot.com/nos-7534.html = $ 49.95

http://www.thetubestore.com/Tubes/6000-to-9999-Types/7543 = $ 6.95

My fault the second link is about 7543 not 7534 


K

[kagliostro]

Two other tubes for the list

6bw6 = a 6v6 in a 9 pin bottle

http://www.r-type.org/pdfs/6bw6.pdf

http://www.r-type.org/exhib/aaa0343.htm

6br7 a small low noise pentode

http://www.r-type.org/pdfs/6br7.pdf

http://www.r-type.org/exhib/aaa0346.htm

K

[kagliostro]

One other tube

the QE08/200

http://www.mif.pg.gda.pl/homepages/frank/sheets/030/q/QE08-200.pdf

this monster tube here compared with KT88 and EL34




was used by Philips in one of his audio amp, the EV4418





K

[shooter]

I've been playing with the 6J6, 2 nos, 2 new, in 3 different circuits and all the tubes are micro-phonic.  Is that normal with 6J6? 

[murrayatuptown]

I'm not sure I understand whether this is a list of known-useful tubes, or just bargains...

Hopefully this fits:

I just bought some odd NOS ones.

8 x RCA 5964. Dual triode with common cathode, 7-pin mini, typ. mu = 39, gm=6000 uS, similar to 6J6? $17.95 shipped
5 x Dumont/ERP 7060. medium mu (40?) triode + small power pentode (2.75 W anode diss. max.), 9-pin mini, 12-15 V filament (13.2 nominal, mobile use originally) $7.95 shipped

I'll do some reading and spreadsheeting before asking how to make use of the 7060's

[PRR]

5964 is common-cathode which is awkward in most guitar amp stages. Aimed for much higher current than we usually need for audio. Yeah, probably a 6J6 with new data and name.

7060 is a fine filler for complex systems like a TV set. 12V heater is not common in guitar amp builds. As a power stage it is barely over 1W, and that at awkwardly low B+ (say 150-200V). The triode is again a high-current lowish gain job. Both together do not make a sparkling mini-amp for guitar.

[DummyLoad]

I've been playing with the 6J6, 2 nos, 2 new, in 3 different circuits and all the tubes are micro-phonic.  Is that normal with 6J6?

IME, yes. there are some commercial/industrial/military variants that may perform better in audio but i haven't tested any. list below. the 7244 looks promising: has stacked ceramic spacers so should be more rigid.

5844
5964
6045
6101
7244
7244-A

--pete

[DummyLoad]

6J6 makes a fine LTPI or bonded single stage - e.g. use as single triode.


--pete

[kagliostro]

Cool Pete 

I've some of those tubes

Franco

[PlumMojo]

6cz5 amazing American tone.(10bucks nos)

Just like a 6973. Like a 6v6 except handle higher voltage.

Also 5v     5cz5 (2bucks )