I've got a box-o-tubes

Bill Terry · From: Bastrop, TX

I have an uncle who was an EE for many years and was an avid electronics hobbyist. When he graduated from Texas A&M they were still using slide rules... so his 'hobby stuff' was typically tube based.

He was cleaning his attic a while back and found a box of old tubes. We had talked many times about tube amps vs solid state and he knew I was a bit of a tube amp junkie.

So... he boxed all that stuff up and sent it to me. There must be about 50 to 60 tubes of various sizes and types. I would say that all of these probably date from the 60's when he fooled around with radios and such.

I've started going through them and found a few that I recognized, a couple of rectifier tubes commonly used in Fender amps, and quite a few 12AX7, 12AT7, ...that sort of thing.

My question concerns how to identify a lot of tubes that I don't recognize. In particular I have a handful of Telefunken tubes that are about the same physical package as a 12Ax7 type tube, but have numbers I don't recognize. Besides the Telefunkens, there are quite a few Sylvania, GE, and Raytheon, plus some other names that I didn't recognize.

I've done a fairly lengthy web search without much success, can anybody suggest some sort of tube x-ref that might be useful? I expect a lot of these tubes are probably for some RF applications and not useful for audio, but I think it's possible I may have some fairly desirable tubes in this lot....

Thanks for any help.

Bryan Knox · From: Gardendale, Alabama...Ya'll come

Bill,
Here is a link to a forum I frequent and you perhaps could find some answers there.

Tell 'em BAMA sent ya.

Amp Workshop Forum

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Prevent Juvenile delinquecy...teach children to STEEL

1976 MSA D-10 8+4, G&L Skyhawk, 1920 Gibson A Mandolin, Fender DPC750 w/Tubefex, 70's Fender Super Reverb, Takamine 6-String

[This message was edited by Bryan Knox on 28 September 2006 at 02:40 PM.]

Brad Sarno · From: St. Louis, MO USA

Bill, it sure sounds like you've got yourself a big box of useless junk. I think you should just carefully send it to me so I can help dispose of it for you. I'm generous like that.

Brad

Bill Terry · From: Bastrop, TX

Hey Bryan, thanks for the link. That looks promising...

Brad, thanks so much for the generous offer

BTW, did I mention there is one (1) KT66 that's opaque gray??? (Unfortunately, no matching tube) is that some milspec thing or something????

and a bunch of Mullards too..

Blake Hawkins · From: Florida

Bill, I'm from the same era as your uncle.
If you can post or send me a list of the tube numbers, I'll tell you the intended purpose of the tube.

Blake

Al Michalczak · From: San Antonio, Texas, USA

Hey Bill, See if any of them will work in my Ampeg amp.Ha Ha!
Al

Jim Phelps · From: Mexico City, Mexico

I've had boxes of tubes (valves, for all the UK members) for years, being an electronic experimenter my whole life... sold all of them before moving, along with 90% of the rest of our stuff.

FYI, I advertised them on Ebay and sold them very easily for quite a good price. I also had a box about a foot square of oldies, 01A's and the like, sold them on Ebay too to a collector in Korea for a very nice price. I wrapped them individually in bubble-wrap and put them in a 1/2" plywood box, they got there safe and he was happy to pay the shipping even with the extra weight of the plywood box.

You might consider selling them on Ebay yourself, but you'll need to inventory the ones you can identify, and specify whether or not you've tested them and then list for example "12 mini unidentifiables not tested" or whatever.

[This message was edited by Jim Phelps on 28 September 2006 at 04:08 PM.]

Bill Terry · From: Bastrop, TX

Hey Al.... Ouch!!! I'll email ya about that amp. My bad...

Thanks for the offers and help guys, I'm gonna put a list together of everything I've got. I may just post it here.

[This message was edited by Bill Terry on 29 September 2006 at 07:12 AM.]

Ray Minich · From: Bradford, Pa. Frozen Tundra

Look for...
5U4
12AX7
12AT7
6L6 with vaious suffixes (i.e. GT, GB, etc)
50L6
50C5
35Z5
35W4
12SQ7
6BQ6
12AU7's make great .22 targets...as do 6SN7's

If you find any 80 tubes, save 'em...

0Z4's ain't worth much...

Gene Jones · From: Oklahoma City, OK USA, (deceased)

*

[This message was edited by Gene Jones on 29 September 2006 at 03:37 PM.]

Ole Dantoft · From: Copenhagen, Denmark

Bill,
The Telefunken tubes will have the European designations on them and if they are physically like the 12AX7 they are most likely these :

ECC83 = 12AX7
ECC82 = 12AU7
ECC81 = 12AT7

They may also be the MillSpec/Special quality versions :
ECC803 or E83CC = ECC83 (12AX7)
ECC802 or E82CC = ECC82 (12AU7)
ECC801 or E81CC = ECC81 (12AT7)

Hope that helps !

Ole

Jim Sliff · From: Lawndale California, USA

I'd be very careful about these:

50L6
50C5
35Z5
35W4

Those are normally used in cheapo "transformerless" amps where one side of the chassis is hot. They are a great way to get electrocuted. Basically, any amp where the sum total of the first numbers of the tubes adds up to 110-120 means line voltage is used for the heaters and there's no power transformer. You can use them safely with a GFCI, but it's still chancy. I've thrown those amps...and tubes...in the trash. Unsafe.

And Gene, a properly maintained tube amp will tonally bury any solid state amp you find, unless your only aim is squeaky-clean tones with no warmth. I have about 20 tube amps, all completely reliable - because I take care of them. Solid state amps are lighter and cheaper, but there's a reason tube amps are still made and used - tone and ease of service.

BTW, I have hundreds of tubes inherited from my father-in-law. And those are guitar amp tubes - I weeded out a couple thousand radio/TV tubes and gave most of them to radio clubs. If anyone needs 6V6's, let me know - I have tons of matched pairs....

[This message was edited by Jim Sliff on 29 September 2006 at 11:12 AM.]

Ole Dantoft · From: Copenhagen, Denmark

In case anyone should be interrested :

The European tube designations are actually quite informative in that the letters actually tell you something about the tubes function !

E means 6.3 Volts, parallel heating
C means Small Signal Triode
F means Small Signal Pentode
L means High Power Pentode

So an
ECCxx is a 6.3 Volt, parallel heated, small signal dual-triode
EFxx is a 6.3 Volt, parallel heated, small signal pentode
ELxx is a 6.3 Volt, parallel heated, high power pentode

The specific purpose of the tube is given by the actual type-number (xx) but just by looking at it, you know a lot about it already. There are a lot more combinations of letters of course.

Ole

John Hauck · From: Long Beach, California, USA

Interesting thread. Glad to hear that there are those out there that have a real interest in tube amps.

Jim, can I ask if you are playing through a tube amp, and what type? I'm presently using a
Rivera for gigs and and older Carvin for practice stuff. Both have the true "tone" you
speak of.

Thanks

Jim Sliff · From: Lawndale California, USA

John - I normally use a Deluxe Reverb around the house. For stage use, a '64 Vibroverb Custom and/or a '69 Pro Reverb - warmer sound than a Twin, and the mix of 2x12" and 1x15" pushes a LOT of air. Sometimes one of those will be swapped out for a 2x10 Holland Little Jimi, an amazing amp for smaller places; not a ton of headroom, but beats all the others hands-down for tone.

Others I'll use are an Ampeg V4 (two power tubes removed); a '55 tweed Deluxe; '66 Bassman modified to '64 specs with slightly more gain on channel 2; various other small tweed Champs and such; and a 1/4watt all-tube Zvex Nano with a 12" Greenback - that sucker screams at low volume! Oh - and a '62 brown Princeton, which has the best low-volume clean tone of any amp ever made IMO. Probably the one I'll use when I get the guts to start recording some of my hopeless playing...

The only solid-state amp I have (I cannot find one with tone I like - they all sound cold and harsh to me, plus are a pain to service) is a Fender GDec, which is tremendous for practice - tweakable MIDI backup band built-in with 50 presets and 50 user patches - great for trying all sorts of styles (blues, punk, surf, reggae, 5/4 jazz, prgressive rock, metal etc). It's not giggable and the tone is mediocre, but it is worth its weight in gold for a beginner - the band is always in tune and the drummer never shows up drunk.

Gene Jones · From: Oklahoma City, OK USA, (deceased)

EDIT FOR CLARIFICATION........
The reason I deleted my post above is because after looking at the thread again I realized that it was a discussion about tube amps among individuals who like tube amps, not about the "pros & cons" of tube amps. More specifically, the discussion is about tubes, not amps.

I shouldn't have intruded on someone elses conversation as I did and my comment was "off topic" so I deleted it. My apology to anyone who may have taken offense.

John Hauck · From: Long Beach, California, USA

Everyone, my appologies for maybe taking this thread to a discussion @ tube vs: solid state amps., when in fact is was @ tube i.d.'s.

John

Gareth Carthew · From: West Sussex, UK

Svetlana used to have a good list on their website. Several hundred tube numbers and their equivalents.
Unfortunatly when last I checked that site had been down for a couple of years.
I know I've got a hard copy of it somewhere. I'll try and dig it out and get it inot soft copy for you.

I also found a great website database some time ago when I was trying to identify my own box of tubes. I'll try to find that too.

I'll get back to you.

Jim Phelps · From: Mexico City, Mexico

Jim Sliff, you're right about some of the old transformerless stuff, many old AC/DC table radios were very dangerous, but you make it sound like it's the tube's fault or that the tube itself is dangerous....

I'm sure you don't mean it that way and you know the tube itself is not going to electricute anyone! I think throwing these tubes away because they have been included in some dangerous circuitry is silly, there are radio collectors who need these tubes and are aware of the dangers of their old radios or whatever.

Besides, they are also used in many old table A.M. radios that didn't have that problem. Before moving here and selling everything I collected and repaired old radios and many of them had these tubes and didn't have hot chassis.

Better throw away our old Fender amps too, you can get a nasty shock or even be electrocuted if the ground switch is in the wrong position. There's nothing wrong with selling or giving away those tubes if that's his plan.

You can't get rid of everything because someone might hurt themself with it... that's the government's job...

[This message was edited by Jim Phelps on 29 September 2006 at 07:20 PM.]

Bill Terry · From: Bastrop, TX

Thanks again to all for the info.. Gareth, that list would be great if it's something that wouldn't be a huge amount of trouble. Please don't do a bunch of typing.

Regarding topic drift, personally I don't care so much. Tube amps, tubes, it's all the same, I enjoy reading this stuff. I see it as just like a face to face conversation, sometimes the topic wanders. How bout those Dixie Chicks huh?

Gene, was it you who told the story about the Twin Reverb going end over end out of the back of a truck on the way to a gig and ending up in a barb-wire fence? Loaded it back up and went to the gig and it worked? I loved that one.. I'm pretty sure it was somebody here on the forum.

Jim Phelps · From: Mexico City, Mexico

As for 12AU7's making good .22 targets... that's a real shame. They are also used in some amps, and if I'm not mistaken, Brad's Black Box uses one. I think they're the best-sounding audio preamp tube out there.

Jim Sliff · From: Lawndale California, USA

Jim - no I wasn't saying to toss the tubes - just to be caseful with amps that use them. You do NOT want to have a guitar plugged into one of those, hold the strins, and touch an aluminum door - you have a 50/50 chance of getting knocked across the room. In radios it's not an issue as you rarely, if ever, touch a part connected to the chassis and a grounded item.

The Fenders with ground switches are easily modified for safety. Not the transformerless amps.

Yes, those tubes can be saved for the radio guys. But the amps that use them are not safe, period. Plus they are usually cheap, lousy-sounding budget amps to begin with - a manufacturer saves a LOT of money deleting a power transformer!

Gene Jones · From: Oklahoma City, OK USA, (deceased)

Yes Bill, that was me. We were going to a New Years Eve gig at Altus AFB.

However, the same amp that survived coming off the luggage rack at highway speed, didn't survive a later job playing a bass through it!

John Daugherty · From: Rolla, Missouri, USA

Bill, what you need is a tube manual. I haven't bought one in a long time. You might try Radio Shack or an electronics parts supplier.
Here is a link to an online tube database. You may find your tubes listed here:
http://www.nj7p.org/Tube.php
I'll offer a little hint from an old timer with a good deal of education and experience ...... Don't place much faith in a tube checker. If a tube checker shows a tube as "bad", it probably is bad. If it checks "good", it may still be bad. The real test for a tube is to plug it into the circuit it is to be used in, and see if it works.
I don't intend to get into a discussion about tube checkers. This laymans approach should suffice and stay on-topic.

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www.home.earthlink.net/~johnd37

Jim Sliff · From: Lawndale California, USA

The RCA tube manual is a good one, and they can be found cheap on eBay. I'll have to look, I may have a spare....

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