Please give your contribute - add a tube to this list

[kagliostro]

Please add a tube to this list 

At flea market sometime you can find NOS cheap tubes, they aren’t the usual tubes we all remember well, but often they are useable for guitar amp

The purpose of this list is to have a reference as to get when find “on the cheap” tubes that can be used to build amps

this list is based on my limited knowledge 

12ay7
12az7
EL500
EL504
EL509
5879
5654 = Ef905
6ak5 = Ef95
6an8
6an8a
6au6 = Ef84
6bm8 = Ecl82
6gw8 = Ecl86
12dw7 = 7247 = ECC832
EL95 = ½ ell80
6af11
6ac10
12ac10a
6d10

Thanks

Kagliostro

[tubeswell]

ECL80 and ECL82/6U8 (small signal pentode and triode in one bottle)

6P3S (reeeal cheap)

6P3Se (my favourite '5881' at the moment)

6P6 (reeeal cheap 6V6)

6F6G (10W output tube with low input sensitivity - does good at about 300V with an 8k load)

[sluckey]

QK653

 

[kagliostro]

Thanks for adds

Sluckey

QK653

I'm not able to find a data sheet for that tube

which tube is it ?

have you a link for that data sheet or a link to a schematic were that tube is used ?

----

If requested I can post some link to schematics that use many of the tubes I put on the list

Kagliostro

[DummyLoad]

1614
1619
1621
1622
4E27A/8001/5-125A
5932
5933
6021
6072
6111
6112
6201
6384
6681
6788
6889
6AB4
6AT6
6AV6
6AY11
6C10
6CA5
6CH6
6CU5
6CW5
6CZ5
6CM6
6DT8
6DY7
6DZ7
6GK6
6HC8
6JB5
6LU8
6Q11
6T10
6U10
7C5
7C7
7EY6
7F7
12BZ7
12DT8
12HL7

[DummyLoad]

QK653

 

tease!

5.3MW? really?

[kagliostro]

QK653 = Amplitron tube

I think my ears will stop at frequencies slightly lower 

Kagliostro

[kagliostro]

DummyLoad

a big list of tubes

are those tubes useables or are tubes that has been used in some amp ?

I'm looking to tubes that were used or can be used as substitution of other more common tubes

I'm not able to plan the use of an "odd" tube like build a champ with a QB3/300

Kagliostro

[jojokeo]

A few more...
12bh7a
ecc99
6ak6
6am5
6ar5
6bl8
7868
6bq6
6jn6
6y6
50c5

[DummyLoad]

a big list of tubes...

you asked... 

are those tubes useables or are tubes that has been used in some amp ?

some have - some are tubes i have experimented with or want to experiment with.

I'm looking to tubes that were used or can be used as substitution of other more common tubes

sorry, i did not filter on that criteria. some of them are drop in like 12AZ7, 12DT8, 12BZ7, 6072, 6201, 6681, etc.

--DL

[sluckey]

5.3MW? really?

Yep. I run mine cool at 4.5MW. Psssh... That's peak power with a duty cycle of 0.00072. P_avg is only about 3.2KW.

[sluckey]

I think my ears will stop at frequencies slightly lower

Oh you can hear it just fine. Mine is pulsed 360 times per second. Everything in the transmitter room sings that note. Heck, I can sync a scope just with the air! And when the waveguide arcs, you can hear it all over the 2 acre compound. Probably not a good choice for guitar. Forget the roady. You need the whole tractor/trailer!

Sorry, I couldn't help myself...

[kagliostro]

Hi Sluckey

I think you must see this

this is only 50KW but I think that can be enough ..........................

 

Kagliostro

[kagliostro]

Well yesterday I was to the Marzaglia (MO - Italy) Radio Amateur Flea Market

and I got a few tube on the cheap (only the Sylvania 5879 was at normal price)

2 x 6201 / JG-12at7 - General Electric NOS (from military stock) - € 3.00 each
1 x 12SN7 - Sicte (old Italian Brand) NOS = € 1.00
2 x 6ak5 - SFR (old France Brand) NOS = € 3.00 each
1 x 6au8 - Westinghouse NOS = € 1.00
2 x 12av6 - Thungsram NOS = € 3.00 each
2 x 12at7 - Siemens NOS = € 3.00 each
1 x 5879 - Sylvania NOS = € 10.00
1 x 5879 - RCA NOS = € 3.00
1 x 5879 - Branded Tektronix inc = € 5.00 (don't think is NOS, it comes in a white box printed only 5879)
3 x 14gw8 - PCL86 - Giant Electronics Brand (???) NOS = € 1.00 each
1 x 6ar11 - General Electric NOS = € 1.00

any suggestion of use for the 6ar11 compactron tube ????? I got it as it was with other "on the cheap" tubes




Kagliostro

[DummyLoad]

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.

--DL

[darryl]

any suggestion of use for the 6ar11 compactron tube ?

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. 

[DummyLoad]

it seems that the 6BN11 would be a better fit. sharp cut-off. similar slope - albeit sightly higher... 12BW11 is a closer match to the AR, but is also a dual sharp cut-off pentode.

i'd bank on the 6LU8 1/2 kind_of_12AT7_like triode and 14W beam pentode w/ moderately high slope ~9500umohs.

something else that looks interesting... the 6AL9 - the pentode is extremely high slope, akin to 8417 yet higher still, but w/ a 10W plate rating in sweep duty. the triode is hi-mu similar characteristics to 1/2 12AT7. without # crunching, i'm thinking a single tube "clean" geetar amp may be possible with <300V B+. i'm thinking however, that one caveat is that pentode could have an achilles heel as the 8417 does - the elements are bound to be very close together to realize such a high slope, and therefor may be fairly prone to arcing...

i think the next "odd ball" amp i put together will be going down the 6LU8 road. AFTER i finish the PRR/ISOdummy 4E27A A1 glo-champ amp.

--DL

oh yeah, add...

6AL9
6FJ7 -  compactron similar to 6DR7 (possible reverb driver or triode output amp)
6FM7 - yet another compactron similar to 6DR7.
6FY7 - lower pdiss of above.
6T9 - *very* rare - compactron triode similar to 1/2 12AX7 and pentode is 6V6ish...

[darryl]

6T9 - *very* rare - compactron triode similar to 1/2 12AX7 and pentode is 6V6ish...

The 6T10 is far more common. It has the same power pentode as the 6T9, while its "dual control" pentode section can be triode connected. Makes a nice 8-watt push-pull amp . . .

[kagliostro]

Thanks for infos

may be is better the 6AR11 rest in my junk box (at € 1.00 I can permit myself to get a "wrong" tube)

I'm still collecting spare parts to build the 6AF11 "Squirrel Monkey" amp, results are sure because the project was build and tested

Kagliostro

[PRR]

> AFTER i finish the PRR/ISOdummy 4E27A A1 glo-champ amp.

GU81M. 45 Euro. Data

[PRR]

> 6AL9 - the pentode ... a 10W plate rating in sweep duty.

No. VIDEO-amp duty.

Sweep tubes ideally have low dissipation, but when things go wrong, dissipation goes high. They must be specified with a large margin.

A Video Amplifier is a plain class-A amp. It runs hot. It isn't going to get much hotter from minor errors or drift. It is in fact more robust than a transformer-coupled SE audio power amp because the video amp is resistor-loaded and an increase of current makes voltage decrease.

Look at the picture (there's on on eBay today). That plate is not as bg as EL84, maybe 6AQ5. It barely looks like 10W Design Max. The "Typical" condition is 7 Watts dissipation.

It could be a one-bottle small-Champ, ~~3Watts.

[DummyLoad]

> AFTER i finish the PRR/ISOdummy 4E27A A1 glo-champ amp.

GU81M. 45 Euro. Data

no wai jose!

1.2KV Va? that ain't happening + i'm getting much to old to muscle 100# parts around.

maybe if i take up amateur radio as hobby.

45 euros... not a bad price for such a beastly tube.
   

[DummyLoad]

No. VIDEO-amp duty. ....

ack! understood.

don't know why i was thinking vert. sweep & datasheets clearly state VIDEO AMP?

a 3W champ w/ <300V B+ wouldn't be a bad thing. might make a decent first timer build & sockets are still plentiful. maybe throw the 3W at a quirky webber  6x9.   

looking at pic on fleabay - at first glance 6AL9 does seem to be a bit on the wimpy side. but from a height/circumference ratio perspective, after a good stare, it does seem to be similar to 6AQ5 in surface area, perhaps a bit less.

--DL

[kagliostro]

GU81M

not sure that those I've seen are exactly that tube, but often at Ham Fest I've seen on sale tube that looks very close to that

at the Radio Amateur flea market in Marzaglia, in 2010, in the ARI (Italian Radio Amateur Association) stand there was an audio amp with one of those big horned tubes without speaker, sound was coming from a plasma flame


Kagliostro

[3choplex]

6SF5 /  12SF5. Hugh mu single triodes. I have been very happy with the 6SF5s in my most recent build. I think they run about $5 a piece.

[Geezer]

How about different filament voltages?
You can get NOS tubes that would cost 10x to 20x more IF they were 6.3v heater versions. Filament transformers are cheap in comparison. I have used many of these tubes with excellent results! Most I've found are 50's/60's/70's manufacture, same basic tubes but different heaters.

An added bonus is that as the filament/heater voltage goes up, the current needed to heat them goes down, so smaller rated transformers can be used. For example, a 6L6GA will eat 900mA, but the 19BG6GA only needs 300mA! You can buy a smaller/cheaper filament tranny, PLUS your main PT will run cooler with the lower demand on the 6.3v winding.

EL84/6BQ5 (also 6GK6 already mentioned above) = 10BQ6 (10v), 10GK6 (10v), 16GK6 (16v...$2 each), 29GK6 (29v)

6BM8/ECL82 = PCL82/16A8 (16v....$6 to $8 ea), UCL82 (50v)

6L6GA = 19BG6GA (19v)....most places I checked have these for $1 ea


Those are just the few I have used.......

[PRR]

> 6SF5 /  12SF5. Hugh mu single triodes. I have been very happy

6F5 is the direct ancestor of 12AX7. 6SF5 is the same without a grid-cap. Same specs. 12AX7 just puts two 6F5 in one smaller bottle with the same total heater demand.

While nominally "same specs", F5 and AX7 are clearly built differently, and as a musician you may hear a difference.

---------------------

> voltage goes up, the current needed to heat them goes down, so smaller rated transformers can be used.

Transformer cost is (should be) proportional to V * A. 6V 0.3A and 12V 0.15A are both 1.8 Watts and both would be wound on a 2VA core and sell at the same price.

True, there's often odd-lots and just odd pricing. 10VA-50VA is often cheap in 24V as excess industrial control parts. Radio Shed used to sell a 2VA, a 4VA, and an 8VA all at the same price (high but not excessive for retail).

[RicharD]

You should always keep an eye out for the unobtainable 6386. 

[kagliostro]

You should always keep an eye out for the unobtainable 6386

NOS NIB $ 249.00

http://cgi.ebay.com/1-NOS-NIB-1959-GE-5-Star-6386-tube-Blk-P-3mica-bent-/270612737987?pt=Vintage_Electronics_R2&hash=item3f01c6afc3

yes I must remember that tube when I'm at Ham Fest  

Kagliostro

EDIT: I've just read that can be try to substitute the 6386 with a pair of 6BJ6 - 6BA6 triode connected and that tubes are not very expensive - remains the pleasure of the hunt for a rare tube, if found on the cheap .....................

[RicharD]

Manley makes what's called a "T-Bar" mod that converts a single 9 pin socket to 2 - 7 pin sockets for just such a substitution in their earlier vari-mu compressor.  Apparently this tube was only used in a couple of thangs ever, both being compressors.  I guess the factories didn't make very many of these.  Supposedly JJ is making a reissue and it's like 2 bills as well.  Where the rub lies is you need a bunch of matched bottles in parallel, but if you find one for a dollar in a candy dish, it's worth it to flip.  Not much use for geetar amps but great fleaBait.

[tubeswell]

How about different filament voltages?

6BM8/ECL82 = PCL82/16A8 (16v....$6 to $8 ea), UCL82 (50v)

Or for that matter a 6GW8/ECL86 = 6.3V 700mA filament - the triode is the same as a 1/2 12AX7 and the pentode is similar to an EL84. (i.e.: like a 'more powerful' ECL82)

[DummyLoad]

How about different filament voltages?

6BM8/ECL82 = PCL82/16A8 (16v....$6 to $8 ea), UCL82 (50v)

Or for that matter a 6GW8/ECL86 = 6.3V 700mA filament - the triode is the same as a 1/2 12AX7 and the pentode is similar to an EL84. (i.e.: like a 'more powerful' ECL82)

one of my prized finds at hamfests. i designed a guitar amp based around a pair of those not long ago. they are also used in the hammond AO-44 reverb unit and i'm still on the lookout for one that costs less than a good steak. ebayers are wanting insane prices for that stuff now.

another consideration?

6KY8 - 12W BPP & hi-mu triode in a novar pkg. w/ exhaust tip (needs 9 pin sockets w/ a hole in the center). looks kind_of_similar to 6BM8 but g2 slope comes in at lower voltage and max V rating is 150V for g2 - Vg2 would need to be kept in check. triode looks to be similar to 1/2 6SL7. selling about 3-5bux on ebay.

http://tubedata.milbert.com/sheets/049/6/6KY8A.pdf

[kagliostro]

Hi DummyLoad

6KY8 a 12W plate dissipation tube - thanks

........... please can you translate BPP ............

BPP = ?? (this day was very hot and hard job so .....................)

Thanks

Kagliostro

[DummyLoad]

Beam Power Pentode...

 

[kagliostro]

    

I'm tired ............. I was thinking <B = ????> <PP = Push-Pull> 

thanks

Kagliostro

[mat janssen]

I have got an amplifier with 4 x 807 as end penthode.
Also usable !

[kagliostro]

807

that is a fine tube

also some old Geloso amplifiers used that tubes

that is a well known tube in RF use and also in AF can give good results

Kagliostro

[kagliostro]

I noticed that i have committed another error (in addition to purchasing the 6AR11), thinking to 12AV7 I bought 2 x 12AV6

http://www.nj7p.org/Tube4.php?tube=12AV6
http://www.nj7p.org/Tube4.php?tube=6AV6

assuming the double diode section is of no use in guitar amps, what can I do with the triode section of this tubes ?

Can I compare this 12AV6 to a tube of the 12**7 series ? which one ?

Thanks

Kagliostro

[DummyLoad]

Can I compare this 12AV6 to a tube of the 12**7 series ? which one ?

6AV6 w/ 12V filaments

1/2 12AX7 ignore the diodes.

--DL

[kagliostro]

1/2 12AX7

That is fine

Thanks

Kagliostro

[kagliostro]

Jojokeo told 6bq6

now I can got some 6bq6gtb on the cheap

(also they are cheap at thetubestore http://thetubestore.com/nos-6bq6.html $ 3.95 each)

what can I do with this tube (BPP <=  ) ?

which B+ voltage for plates and which OT primary impedance ?

have you schematics of amps using this tube ?

Thanks

Kagliostro

EDIT p.s.: I've read somewere that a PP of 6bq6 can be supply at 320/350v on plates ( ??? ), 150v on screen and 4kohm OT - what about biasing ?

[kagliostro]

A friend want to give me an RCA CRC-6080-WA tube

I've seen only schematics that uses this tube for stabilized power supply

have you never seen an audio use for this tube ??

Thanks

Kagliostro

[DummyLoad]

http://www.pmillett.com/file_downloads/ax_lowmu.pdf

[kagliostro]

Thanks DummyLoad

I was thinking a 13W + 13W plate dissipation triode was used for power section not preamp

Kagliostro

[PRR]

http://www.mif.pg.gda.pl/homepages/frank/sheets/164/6/6AS7.pdf

[DummyLoad]

6AS7 being lo mu has very high drive requirements - usually near the B+ required. this guy in 1949 solves the problem by using 8:1 inter-stage step-up transfo.  the design is an unlikely candidate to be a guitar amp.

http://www.bonavolta.ch/hobby/en/audio/6as7_1.htm

the best solution would be two supplies - one ~250V high current for the output stage, the second a high voltage (~350-400V) low current for the pre-amp/driver.

looks like use of the 6AS7/6080 wouldn't be very economical or practical.

[kagliostro]

Thanks PRR for the attached link

Thanks DummyLoad for the schematic you posted

http://www.bonavolta.ch/hobby/en/audio/6as7_1.htm

it is interesting to me be because of the way they act the cathode bias of the power tube

as I can see a solution near that I was thinking was used in the past and feasible

http://www.el34world.com/Forum/index.php?topic=11828.0

looks like use of the 6AS7/6080 wouldn't be very economical or practical

after the explanations I can uderstand and agree with you 6AS7 isn't a tube devoted to guitar amp use

Kagliostro

[kagliostro]

Today I was to another Radio Amatuer Ham Fest

I got an old italian amp (GEM Super Deluxe 50 R) a 11 tube amp two channel with 4 el84 final tubes + reverb and trem

Also I got

2 used 5751 (till now the only 5751 I've seen at flea market, here that tube is not so common)

4 NOS 6005w Siemens tubes

1 used 5687wb tube (seems to be JAN GE)

the seller told me that 6005w is the same of 6aq5 tube (military version)  

but I find only datasheet for 6005 tube, not 6005w

can I assume the 6005w and 6aq5 (el90) are the same tube ?

as far I can understanf from a datasheet a PP of 6aq5 needs 250v plate and 10Kohm load (10W out)

what will happen If I use those tube with a PP in an 8Kohm load ?

What about 5687we tube ? in guitar amp is that tube usable and if so, where in the circuit ?

MANY THANKS

Kagliostro

[DummyLoad]

I got an old italian amp (GEM Super Deluxe 50 R)

if it's broken, beat it with a prosciutto...  just kidding!! nice score! how does it sound?

the seller told me that 6005w is the same of 6aq5 tube (military version)

6005w is 6005/6AQ5/EL90 same tube electrically. they are military - the "W" designation means just that.

what will happen If I use those tube with a PP in an 8Kohm load ?

nothing bad as long as you keep plate dissipation in check.

What about 5687we tube ? in guitar amp is that tube usable

i wouldn't use it as a gain stage, maybe as a reverb driver or a cathodyne. it has a combined plate dissipation of 7.5 watts or 3.75W/section. it seems as though it would likely be a better choice for hi-fi amp or headphone amp use.

[PRR]

6AQ5 is a small 6V6. It is fine at 250V 10K load, is over-spec at 6V6's 285V 8K load (but usually works fine).

6005 is a high reliability 6AQ5. The W just means it passes military testing.

If you want 6005W to "never fail" (5,000-10,000 hours), keep it down to 250V. If you want a maximum output hot-rod stage amp, go ahead and hit it with 300V, 350V.