Will this chip work? (2023 Update)

Gentlemen,

I have a fairly substantial Hacker Helmsman transistor radio made in 1970 and its audio board has failed. Repair does not seem practicable so I'm now going to replace the faulty board with an IC I've found in my inventory. I'm just wondering if it will be suitable, though. In particular I'm concerned about the line in the datasheet that says it's especially suitable for mains-powered applications. That seems to imply it's a current hog and will drain batteries in short order. This radio runs off batteries, although admittedly quite heafty ones: 8x 1.5V 'D' cells for 12V in total.

Here's the chip:

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I'm sure there are better-suited ones out there, but I'd far sooner use one 'from stock' unless there's a compelling reason not to.

Observations from contributors north of the Tropic of Capricorn only, please. Thanks!

Reply to
Cursitor Doom
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On a sunny day (Sun, 2 Jan 2022 18:27:08 -0000 (UTC)) it happened Cursitor Doom snipped-for-privacy@notformail.com wrote in <sqsqps$vv9$ snipped-for-privacy@dont-email.me:

LM380 2.5W 10-22V LM386 about 1W 4-12V Both are single supply and classics.

As to transistors, just buy some BC107 BC109 and play with those. Never mind the f*cking math, these are current amplifiers. with high Zout high beta NPNs

Reply to
Jan Panteltje

The problem with the 380 is the 10V min. The battery pack is 12V so when that starts to sag.... Really not enough headroom. Shame, as the Iq is very low; about a quarter of the draw that the chip I found is quoted at. The 386 wouldn't have enough grunt, I'm afraid. :(

Reply to
C Doom

On a sunny day (Mon, 03 Jan 2022 15:31:21 +0000) it happened C Doom snipped-for-privacy@notformail.com wrote in snipped-for-privacy@4ax.com:

The 10V minimum is actually 8V depending how you read the datasheets:

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8V your battery is likely empty?

Reply to
Jan Panteltje

This is odd. The datasheet I found clearly says 10V min!

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I'd sooner have a bit more headroom to be on the safe side.

Reply to
Cursitor Doom

On a sunny day (Mon, 03 Jan 2022 19:13:24 +0000) it happened Cursitor Doom snipped-for-privacy@notformail.com wrote in snipped-for-privacy@4ax.com:

Sure, if you look at the current drain versus voltage graph it still is working down to 8V You will have more limited output of course. I have a LM380 somewhere, could try IF I can find it. Used that chip several times in the past, beware it is class AB, so it will pull down your battery on high output so I think there is your limiting factor. But it was just a suggestion... There maybe be more suitable ones, but that chip has proven itself here. You can do it discrete too, just a few transistors, been there done that long before LM380.

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5pcs for 7$50

Reply to
Jan Panteltje

I'm sure I have one (at least here already). The problem is locating it out of the thousands of siimilar looking ICs. I usually just give up after a few hours and order one. Then a couple of months later I'll find I did already have one - or a dozen. I can't win. :-/

Reply to
Cursitor Doom

The John Doe troll stated the following in message-id <sdhn7c$pkp$ snipped-for-privacy@dont-email.me:

And the John Doe troll stated the following in message-id <sg3kr7$qt5$ snipped-for-privacy@dont-email.me:

And yet, the clueless John Doe troll has itself posted yet another incorrectly formatted USENET posting on Wed, 5 Jan 2022 02:04:39 -0000 (UTC) in message-id <sr2ubn$jeh$ snipped-for-privacy@dont-email.me.

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Reply to
Edward Hernandez

On a sunny day (Tue, 04 Jan 2022 22:20:55 +0000) it happened Cursitor Doom snipped-for-privacy@notformail.com wrote in snipped-for-privacy@4ax.com:

Yes, same problem here, after I moved house things are in some of the 40 big boxes many full of electronics. I have some sorted out now. I took pictures of the contents with my smartphone, that does help and prevenst a lot of heavy lifting...

Reply to
Jan Panteltje

If you don't find your 380 you could always use an opamp and a class B germanium output pair. Done that before. Just be careful about temperatures with geraniums. Ge is much more forgiving in class B than silicon.

Reply to
Tabby

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