Anybody have scan of AN-483B (Motorola)?

[Conrad Hoffman]

This was the old Motolora app note about medium power audio amps using darlington devices. I had it, can't find it anymore, can't locate it on the 'net, and it's driving me crazy! Happy to trade for a scan of some other useful thing- old Dynaco catalog, Onkyo T-15 tuner service manual, SWTP Tiger amp docs, or whatever else might be useful from my library of obsolete technology

[sixtek]

Hi,

I've found AN485-D, "High power audio amplifiers with short circuit protection", from 1985 by Motorola.
35>100W amplifier design with CFP output.

Maybe you tought of 485D application note instead of "483B"?

http://sixtek.uw.hu/an485d.pdf

[Conrad Hoffman]

I found that one also, but there are several audio related app notes that disappeared from Motorolas listing quite early. Possibly these "special" notes were only released to members of the secret audio society. You are a member, aren't you? Pretty sure my number is correct, as I built several amplifiers based on their circuits. I'm going to try the local antique wireless people, as they have a large collection of old data. I notice that nobody seems interested in darlington outputs these days, but I recently tested the amp I built from the app note, and was surprised at how well it did. I also used to have an Integral Systems 200 amp. It did 100W/ch using a single pair of darl outputs on huge spider heat sinks. Seemed risky to me, but it worked well and was very inexpensive. Thanks.

[Juergen Knoop]

I notice that nobody seems interested in darlington outputs these days

tsss, the black devil by Georg Schwarz/Gerhard Haas is still on my wishlist.
It features a single ended input stage, one transistor for voltage gain and a pushpull darlington output stage.
The authors promise "tube sound" with second harmonic distortion only.
And of course it has electrolytics at input and output!
I have still two pairs of BDX64/67 and I will try them in this circuit.

[fotios]

Originally posted by Conrad Hoffman
This was the old Motolora app note about medium power audio amps using darlington devices. I had it, can't find it anymore, can't locate it on the 'net, and it's driving me crazy! Happy to trade for a scan of some other useful thing- old Dynaco catalog, Onkyo T-15 tuner service manual, SWTP Tiger amp docs, or whatever else might be useful from my library of obsolete technology

Do you mean this?

[Conrad Hoffman]

Yes indeed, that would be the one! What sorts of things are you interested in that I might be able to scan in return?

Regards,
Conrad

[mikeks]

Original app_note available in .pdf. Send me mail.

[fotios]

Originally posted by Conrad Hoffman
Yes indeed, that would be the one! What sorts of things are you interested in that I might be able to scan in return?

Regards,
Conrad

I hope Mikeks that he solves your request. If it is not so, please inform me to send you the document in photographs because i have not scanner.
Fotios

[Valvepower]

Hi,

This is my first post here.

I’ve located this thread after searching for the Motorola application note AN-843A for Darlington transistors.

I noticed one of the members in this thread had a copy, in PDF form, but before I contacting the member directly, I felt it only right to resurrect the thread before doing so.

The reason for trying to locate the AN-843 application note is because I need to gather some background info on the HH TPA25-D power amplifier, which by my deduction uses Motorola Darlington transistors.

I’ve seen a summary of the application note in a 1971 copy of Wireless World, but I’d like to locate the original Motorola version.

A circuit for the HH TPA25-D would be nice at some point, but that’s for a separate post!

Regards.
Terry.

[lineup]

En esta práctica se analizará la etapa de amplificación de audio de la figura 4 del boletín
técnico de Motorola (nota de aplicación AN-483B).
http://www.ing.unlp.edu.ar/electrote...celec/lab5.pdf