Any current sources for LM308 out there?

Fama said:
Was there any reliable way to check if you have legit LM308's? Trying it in a circuit without the compensation cap seems to be the way to go? Or alternatively if pin 5 is connected to something else, although OP07's don't seem to have it connected either.
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Click your heels together and pray to Aslan that Falcor delivered the goods to the Shire.
Seriously, what it this obsession with part branding lately?!? If it works, it’s legit. Full stop.
 
Betty Wont said:
Click your heels together and pray to Aslan that Falcor delivered the goods to the Shire.
Seriously, what it this obsession with part branding lately?!? If it works, it’s legit. Full stop.
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Come on now, I'm rational and sensible like 90% of the time, let me have some magic voodoo parts at least some of the rest of the time!
 
Betty Wont said:
Click your heels together and pray to Aslan that Falcor delivered the goods to the Shire.
Seriously, what it this obsession with part branding lately?!? If it works, it’s legit. Full stop.
Click to expand...

Why do you always have to take a dump on someone when they want to try a 'magic beans' part for themselves? It's not like it does any harm. At some point you'll have tried these yourself and decided they're not really any different from another part. Well most other builders want to try them too and I don't see what's wrong with that?

Edit - I just reread this and it's harsher than I intended. I'm on day 4 of quiting smoking and I'm getting twitchy.
 
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I have LM308s in the metal can format and I am located in Australia. I have had these for years in a drawer with a ton of other stuff which I am selling off on other sites. As I am located in Australia postage to the US with tracking is $20, I can put them in an envelope for a few $ but there is no tracking for that. What is a reasonable price for an LM308 in a metal can?

Tried taking some images with the phone, there is a mixture of National and Motorola LM308s.

I have used them in various things such as this 308 distortion as I mostly do synth stuff (I made a few of these):

308 Distortion Module – Synthrotek

www.synthrotek.com www.synthrotek.com

Also what other parts are people after I can check what I have as an example CA3045 (ceramic 3046), CA3046, CA3086, LME497010HA, LME49713HA, LME49720HA, CA3080 (single OTA), CA3280 (dual OTA), CA3060 (triple OTA) etc.
 

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SillyOctpuss said:
...I'm on day 4 of quiting smoking and I'm getting twitchy.
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STAY THE COURSE!

Ewe kin dewit!

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Worked out a reasonable price for LM308 Metal Cans:
10pcs $6 each.
25pcs $5 each
50pcs $4 each.
$20 delivery to USA
+4% for Paypal (to cover the fees unless sent as friend).

Less than 10pcs is not worth it for me as I have to fill in customs forms etc., to send them O/S.
When these are gone there is no more.

50 have been SOLD already.
 
I bought a few from Jameco not that long ago.
Also a source of 1N270 germanium diodes (caution when bending leads, these babies will crumble if you look at them wrong)
 
Chuck D. Bones said:
How did you test the Jameco parts? They do not have a good reputation.
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Haven’t tested them yet. They look legit, though. May pop one into a Rat I have sitting in my drawer to see how they compare.

Was hoping I could get a dual rat board done that I bought from a private party so I could have one side with LM308 and the other OP07 to make it easy to AB, but that is the one board I can’t get to work for the life of me (thinking there’s some oscillation issues).
 
I made a dual Rat breadboard for comparing LM308s. The easiest test is to measure the opamp's power supply current. Typical range is 250μA to 350μA. Most other opamps are much higher. If you have a scope, drive one with a 1KHz square wave and measure the slew rate.

The Rat has a lot of gain, so if the board layout is not right, oscillation could definitely be a problem. No oscillation on my breadboard.

Can you post a photo of the markings on the can? Or at least provide the P/N, LDC and mfgr.

(several posts up)
Hey! That's Eddie Van Halen's ex! you suppose they watched reruns of One Day at a Time together?
 
Chuck D. Bones said:
I made a dual Rat breadboard for comparing LM308s. The easiest test is to measure the opamp's power supply current. Typical range is 250μA to 350μA. Most other opamps are much higher. If you have a scope, drive one with a 1KHz square wave and measure the slew rate.

The Rat has a lot of gain, so if the board layout is not right, oscillation could definitely be a problem. No oscillation on my breadboard.

Can you post a photo of the markings on the can? Or at least provide the P/N, LDC and mfgr.
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No scope anymore. Sold it when I shut down the amp repair/build business and now I’m a weekend warrior I wing it with my fluke meter.
They are 8-pin DIP and not the metal can version. But I’ll get what I can this weekend for you!

And I’m definitely thinking oscillation: all components verified, and signal on output of opamp lower than input, and as I probe it takes nothing to get clipping LEDs to light up hard with no signal and stay lit. Kinda just pushing it aside and doing some other builds and figure I’ll move back to it some other time…
 
The NatSemi logo on the pdips isn't even correct
It's not thicker in the middle. I can't find them currently. May have tossed them. I'd stear clear of the jameco pdips for sure. I bought a ton of logic stuff from them too. Hopefully it's not all fake.
 
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