The unknown parts thread / General Chatting / Forums

Forums

4hv.org :: Forums :: General Chatting

« Previous topic | Next topic »

The unknown parts thread

first previous 3 4 5 6 next

Move Thread

LAN_403

Proud Mary

Sat Sept 04 2010, 06:15PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Oidium45 wrote ...

NEVERMIND EVERYONE! IGNORE THIS POST. THE NUMBERS WERE WORN OFF AND IT TURNED OUT IT WAS A 6BL6 NOT 3BL6.

Here is one that I would greatly appreciate a datasheet for.

Labeled Sylvania 3BL6 and stamped around the brass portion 205L4.

Thanks!

6BL6 is a broadband reflex klystron.

As it's designed to work with an external cavity, and has a really wide tuning range, you could have a lot of fun with it.

803

Sat Sept 04 2010, 06:16PM

Registered Member #2807 Joined: Fri Apr 16 2010, 08:10PM
Location:
Posts: 191

radiotech wrote ...

The GE 213 could be replaced with a MPS2222A. There is at least one other GE4 by General Electric and your's isnt it.

Starting about 50 years ago there were about 12 fits-all transistors that could replace many and by 1970 those few could replace about 10,000 types. The 213 and the 4 were fits-all types made by GE to sell into the hobby market and the transistor radio repair market.

What would the antique radio crowd pay for these tubes?

I collect antiqe radios and not much. $1-3 bucks if new, used, $10 for the lot. $20 if new. what are the parts numbers? I bet they were used in cheap, AA5s.

radiotech

Sat Sept 04 2010, 06:20PM

Registered Member #2463 Joined: Wed Nov 11 2009, 03:49AM
Location:
Posts: 1546

heres a listing for 6BL6 as well see

Also shown (poor photo) top unit is klystron tester.

Adam Munich

Sun Sept 05 2010, 02:17AM

Registered Member #2893 Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2242

So nobody has more info on the transistors?

MinorityCarrier

Sun Sept 05 2010, 03:07AM

Registered Member #2123 Joined: Sat May 16 2009, 03:10AM
Location: Bend, Oregon
Posts: 312

Grenadier, my old falling-apart 1982 GE semi. catalog has the GE 213 listed as a silicon NPN 3rd TV IF amp, which I seriously doubt is what you have pictured. Those look like vintage germanium transistors. Check one's base-emitter with a handheld DVM diode checker to see what the Vfwd is.

In the catalog 803 put up, the GE 4 pictured is a package style used almost exclusively for germanium power transistors. The GE 4 you have pictured may have had a number rubbed off.

Back in the late 50's and very early 60's, it was the wild west for transistor ID's (I first played with the CK-722 in 1963), so you'll maybe need to find an antique transistor radio collector/restorer to find out what those are.

radiotech

Sun Sept 05 2010, 03:44AM

Registered Member #2463 Joined: Wed Nov 11 2009, 03:49AM
Location:
Posts: 1546

Anyone who restores old electronics for long enough will start analytical thought about why circuits wont work and wont build new stuff full of bugs.

Adam Munich

Sun Sept 05 2010, 04:06AM

Registered Member #2893 Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2242

Well the back of one says PT-2, while the other says GE-1. They were all NOS, and no numbers/letters have been worn off.
They're definitely germanium ones too.

Proud Mary

Sun Sept 05 2010, 05:30PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Grenadier wrote ...

Well the back of one says PT-2, while the other says GE-1. They were all NOS, and no numbers/letters have been worn off.
They're definitely germanium ones too.

Even very modest multimeters are able to test hfe, which is well on the way to finding a suitable use for them.

Steve Conner

Sun Sept 05 2010, 05:49PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Plasmana wrote ...

They are made by Motorala and the part number is SJ2709 with 352 underneath it.

I know this one! "SJ" transistors are regular Motorola parts specially selected for big customers who have enough clout to say, "We want something like a MJ15003 but with a little more beta.". One customer like this was Peavey, a big manufacturer of PA and musical instrument amps. If you head over to the Music Electronics Forum, there's a Peavey authorized tech there who posted a copy of the cross-reference guide.

Germanium transistors are only good for one thing, building a Fuzz Face or Dallas Rangemaster for your electric guitar. And most of them aren't even good for that as they have too high leakage. (A forum member kindly sent me a half dozen a while ago, and I found two that worked pretty well in the Fuzz Face circuit, but the rest were unusable.)

The hfe function on a multimeter is fooled by leakage current and will give an abnormally high reading.

Matt Edwards

Mon Sept 06 2010, 12:07AM

Registered Member #2838 Joined: Fri Apr 30 2010, 07:55PM
Location: tehachapi, CA
Posts: 333

PROUD MARY- maybe you could shoot some ideas my way?

first previous 3 4 5 6 next

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob