Is there any way to test a STK463 Audio Amp chip?

Is there any way to test a STK463 Audio Amp chip? (without having some
sort of special factory analyzer)?

I had a Marantz SR1000 receiver given to me. I plugged it in, and got a
few seconds of hum, panel lights dimmed also. Then smoke appeared. I
found the source of the smoke, a small electrolytic cap blew, and left
the board wet.

I may try to replace that cap, but I suspect there is more wrong. I dont
usually work on anything containing IC chips. And Im sure if that big
amp chip is bad, it would be very costly. (Not worth my time or money).
But I'd be willing to test it if I know how.

By the way, the power supply is working. As soon as I unplugged it
(after the smoke), I got a good spark when I shorted the main (large)
filter caps.

 

[Trevor Wilson]

On 19/04/2019 10:01 am, tubeguy@myshop.com wrote:

Is there any way to test a STK463 Audio Amp chip? (without having some
sort of special factory analyzer)?

**Yep. Download a data sheet, build up the test circuit and test.
Alternatively, plug it into the existing product, crank the unit up on a
variable auto-transformer (aka: Variac™). Watch Voltages and currents
carefully.

I had a Marantz SR1000 receiver given to me. I plugged it in, and got a
few seconds of hum, panel lights dimmed also. Then smoke appeared. I
found the source of the smoke, a small electrolytic cap blew, and left
the board wet.

**Which cap? You could analyse the circuit and determine what is causing
the cap to fail (assuming it is not just the cap).

I may try to replace that cap, but I suspect there is more wrong. I dont
usually work on anything containing IC chips. And Im sure if that big
amp chip is bad, it would be very costly. (Not worth my time or money).
But I'd be willing to test it if I know how.

**"Big money"?!! Are you serious? They're like 10 Bucks. 10 minutes of
your time (using a vacuum desolder iron, or 20 minutes with a manual
one), job done. Easy-peasy. Back when I was service manager for Marantz
Australia, I replaced a hundred or so of the things. Not so reliable,
but easy to replace. No fault-finding required.

By the way, the power supply is working. As soon as I unplugged it
(after the smoke), I got a good spark when I shorted the main (large)
filter caps.

**Yeah, no. That ain't real smart either.


--
Trevor Wilson
www.rageaudio.com.au

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

On Thursday, April 18, 2019 at 8:01:25 PM UTC-4, tub...@myshop.com wrote:

Is there any way to test a STK463 Audio Amp chip? (without having some
sort of special factory analyzer)?

I had a Marantz SR1000 receiver given to me. I plugged it in, and got a
few seconds of hum, panel lights dimmed also. Then smoke appeared. I
found the source of the smoke, a small electrolytic cap blew, and left
the board wet.

I may try to replace that cap, but I suspect there is more wrong. I dont
usually work on anything containing IC chips. And Im sure if that big
amp chip is bad, it would be very costly. (Not worth my time or money).
But I'd be willing to test it if I know how.

By the way, the power supply is working. As soon as I unplugged it
(after the smoke), I got a good spark when I shorted the main (large)
filter caps.

Please post the cap that smoked. Its location will help us to provide guidance on repairing this unit. If the STK is bad, a new one can be obtained for $10-$15.

Dan

 

On Thu, 18 Apr 2019 19:18:22 -0700 (PDT), dansabrservices@yahoo.com
wrote:

On Thursday, April 18, 2019 at 8:01:25 PM UTC-4, tub...@myshop.com wrote:
Is there any way to test a STK463 Audio Amp chip? (without having some
sort of special factory analyzer)?

I had a Marantz SR1000 receiver given to me. I plugged it in, and got a
few seconds of hum, panel lights dimmed also. Then smoke appeared. I
found the source of the smoke, a small electrolytic cap blew, and left
the board wet.

I may try to replace that cap, but I suspect there is more wrong. I dont
usually work on anything containing IC chips. And Im sure if that big
amp chip is bad, it would be very costly. (Not worth my time or money).
But I'd be willing to test it if I know how.

By the way, the power supply is working. As soon as I unplugged it
(after the smoke), I got a good spark when I shorted the main (large)
filter caps.

Please post the cap that smoked. Its location will help us to provide guidance

on repairing this unit. If the STK is bad, a new one can be obtained
for $10-$15.

Dan

Will post it when i am back at the shop. I am currently looking for a
schematic to download. Thus far im not finding any.

Thanks

 

tub...@myshop.com wrote:

Will post it when i am back at the shop. I am currently looking for a
schematic to download. Thus far im not finding any.


** FFS use Google.com and " STK463 schem "

Wot a pathetic retard.



..... Phil

 

[Trevor Wilson]

On 19/04/2019 12:45 pm, tubeguy@myshop.com wrote:

On Thu, 18 Apr 2019 19:18:22 -0700 (PDT), dansabrservices@yahoo.com
wrote:

On Thursday, April 18, 2019 at 8:01:25 PM UTC-4, tub...@myshop.com wrote:
Is there any way to test a STK463 Audio Amp chip? (without having some
sort of special factory analyzer)?

I had a Marantz SR1000 receiver given to me. I plugged it in, and got a
few seconds of hum, panel lights dimmed also. Then smoke appeared. I
found the source of the smoke, a small electrolytic cap blew, and left
the board wet.

I may try to replace that cap, but I suspect there is more wrong. I dont
usually work on anything containing IC chips. And Im sure if that big
amp chip is bad, it would be very costly. (Not worth my time or money).
But I'd be willing to test it if I know how.

By the way, the power supply is working. As soon as I unplugged it
(after the smoke), I got a good spark when I shorted the main (large)
filter caps.

Please post the cap that smoked. Its location will help us to provide guidance
on repairing this unit. If the STK is bad, a new one can be obtained
for $10-$15.

Dan

Will post it when i am back at the shop. I am currently looking for a
schematic to download. Thus far im not finding any.

**You're kidding, right? What planet do you live on?

Try here:

https://www.hifiengine.com/manual_library/marantz/sr1000.shtml

Or, for the STK463, here:

https://www.datasheetspdf.com/datasheet/STK463.html

So, do you have the internet there on Mars?


--
Trevor Wilson
www.rageaudio.com.au

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

Trevor Wilson wrote:

Back when I was service manager for Marantz
Australia, I replaced a hundred or so of the things.

** I thought " Service Managers " let others do the soldering iron jockeying?

Not so reliable, but easy to replace.

** Trouble is the part is not internally current or VI limited, so not short circuit proof, relying on DC rail fuses instead.

Reliable enough, long as the user is careful with speaker wiring and such.



.... Phil

 

[Trevor Wilson]

On 19/04/2019 7:21 pm, pallison49@gmail.com wrote:

Trevor Wilson wrote:



Back when I was service manager for Marantz
Australia, I replaced a hundred or so of the things.


** I thought " Service Managers " let others do the soldering iron jockeying?

**When I first started, I had a junior tech to do the work I didn't
like. That said, when I started there, I had no experience with cassette
decks and he did. I was able to learn quite a bit from him. About a year
later, the company ran into financial difficulties and they sacked my
junior tech. Another year passed and the company hired another tech for
me to boss around. I also got a full time spare parts lady.

Not so reliable, but easy to replace.


** Trouble is the part is not internally current or VI limited, so not short circuit proof, relying on DC rail fuses instead.

Reliable enough, long as the user is careful with speaker wiring and such.

**Correct. It was what Marantz called: "value engineering". Up 'till the
SR range, all Marantz receivers and amplifiers employed excellent VI
limiting systems, along with discrete transistor output stages and full
steel construction. When the boss excitedly told me about this "value
engineering" malarky, I grew suspicious. When I saw the result, I was
profoundly disappointed. It was crap. Timber top covers and, in some
cases, Masonite base plates. Urk. Lousy heat dissipation. Gone was the
beautiful backlit dials. It was so sad. Marantz was then (partly) sold
to Philips. Philips actually improved things considerably and the SR
series was consigned to the dustbin of history.


--
Trevor Wilson
www.rageaudio.com.au

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

On Friday, 19 April 2019 11:23:40 UTC+1, Trevor Wilson wrote:

On 19/04/2019 7:21 pm, pallison49@gmail.com wrote:
Trevor Wilson wrote:

Not so reliable, but easy to replace.


** Trouble is the part is not internally current or VI limited, so not short circuit proof, relying on DC rail fuses instead.

Reliable enough, long as the user is careful with speaker wiring and such.


**Correct. It was what Marantz called: "value engineering". Up 'till the
SR range, all Marantz receivers and amplifiers employed excellent VI
limiting systems, along with discrete transistor output stages and full
steel construction. When the boss excitedly told me about this "value
engineering" malarky, I grew suspicious. When I saw the result, I was
profoundly disappointed. It was crap. Timber top covers and, in some
cases, Masonite base plates. Urk. Lousy heat dissipation. Gone was the
beautiful backlit dials. It was so sad. Marantz was then (partly) sold
to Philips. Philips actually improved things considerably and the SR
series was consigned to the dustbin of history.

Sansui similarly suicided. From excellent to junk.

 

[pfjw@aol.com]

> Sansui similarly suicided. From excellent to junk.

Sansui had many things. Lots o' buttons, lots o' knobs, reasonably good build-quality, but absolutely NOTHING to raise its brand above any other contemporary brand from the Pacific Rim. One more jellybean in the bowl distinguishable only by its surface color.

Peter Wieck
Melrose Park, PA

 

On Friday, 19 April 2019 15:56:20 UTC+1, pf...@aol.com wrote:
NT:

Sansui similarly suicided. From excellent to junk.

Sansui had many things. Lots o' buttons, lots o' knobs, reasonably good build-quality, but absolutely NOTHING to raise its brand above any other contemporary brand from the Pacific Rim. One more jellybean in the bowl distinguishable only by its surface color.

Peter Wieck
Melrose Park, PA

That's odd. As I recall Sansui valve amps had excellent sound quality, not great build quality but good enough, and certainly not lots of knobs or buttons. Unfortunately when they transistorised around '70 their quality dropped through the floor.


NT

 

[pfjw@aol.com]

On Friday, April 19, 2019 at 12:08:22 PM UTC-4, tabb...@gmail.com wrote:

> That's odd. As I recall Sansui valve amps had excellent sound quality, not great build quality but good enough, and certainly not lots of knobs or buttons. Unfortunately when they transistorised around '70 their quality dropped through the floor.

And, perhaps, the worst output transformers on the planet at the time, competing with, but not quite as bad as Kenwood. That was their downfall on the tube side. The solid-state side, as previously described.

Their OPTs were known for lots of, but flabby bass, and not much, but sibilant treble.

Peter Wieck
Melrose Park, PA

 

On Friday, 19 April 2019 17:35:19 UTC+1, pf...@aol.com wrote:

On Friday, April 19, 2019 at 12:08:22 PM UTC-4, tabby wrote:

That's odd. As I recall Sansui valve amps had excellent sound quality, not great build quality but good enough, and certainly not lots of knobs or buttons. Unfortunately when they transistorised around '70 their quality dropped through the floor.

And, perhaps, the worst output transformers on the planet at the time, competing with, but not quite as bad as Kenwood. That was their downfall on the tube side. The solid-state side, as previously described.

Their OPTs were known for lots of, but flabby bass, and not much, but sibilant treble.

Peter Wieck
Melrose Park, PA

The one I had gave the Quad II a very good run for its money. Perhaps your comments apply to some earlier model. Their downfall was the excessive voltage used on the valves, 500v on 7189A IIRC. That & the unavailability of 7189A is why they aren't a recommended buy now.


NT

 

[pfjw@aol.com]

On Friday, April 19, 2019 at 1:39:13 PM UTC-4, tabb...@gmail.com wrote:

The one I had gave the Quad II a very good run for its money. Perhaps your comments apply to some earlier model. Their downfall was the excessive voltage used on the valves, 500v on 7189A IIRC. That & the unavailability of 7189A is why they aren't a recommended buy now.

I will spare you my opinion on Quad tube stuff. And, as it happens, their equipment from start-to-finish is vastly overrated - but for a few of their ESL speakers. Operative word being 'few'.

c.f.: Blind squirrels and nuts.

But, that is why there are many flavors of ice cream, and even sherbets for the lactose-intolerant.

Peter Wieck
Melrose Park, PA

 

pf...@aol.com wrote:

** the resident fuckwit on this nG

I will spare you my opinion on Quad tube stuff.

**Thank god for that - now if the retarded nincompoop would just od the same with every other topic.

And, as it happens, their equipment from start-to-finish is vastly overrated

** No Mr Weeky, YOU are vastly overrating your pig ignorant opinions.

Cos you are raving nut case of the worst possible kind.



..... Phil

 

Trevor Wilson wrote:

** I thought " Service Managers " let others do the soldering
iron jockeying?


**When I first started, I had a junior tech to do the work I didn't
like. That said, when I started there, I had no experience with cassette
decks and he did. I was able to learn quite a bit from him.

** I gave up all interest in working for hi-fi importers when I heard that 90% of the work was in fixing damn cassette decks. Although I have worked on a few for regular customers, I have never owned one.

However, I did buy a Brenell RR transport fitted with "Sonic" heads from Geoff at RDS in the late 1970s. Built all the necessary electronics and had it working nicely - the goal being to record live music broadcasts from 2MBS FM.

Unfortunately, even at 15ips the loss of quality was too great for my liking and I also found the same thing when I tried a Teac 1/4 inch half track in the role. Modulation noise, tape hiss and loss of definition ( IM distortion ?) were all too evident. Mind you, I was listening via Quad ESLs.

The only tape recorder that came close was a VHS Hi-Fi video loaned to me by a customer. That could copy an all digital CD of classical piano with negligible loss. Funny how they never caught on as audio recorders.

Consumers all seem to prefer convenience over sound quality.



..... Phil

 

On Saturday, 20 April 2019 01:35:42 UTC+1, palli...@gmail.com wrote:

** I gave up all interest in working for hi-fi importers when I heard that 90% of the work was in fixing damn cassette decks. Although I have worked on a few for regular customers, I have never owned one.

However, I did buy a Brenell RR transport fitted with "Sonic" heads from Geoff at RDS in the late 1970s. Built all the necessary electronics and had it working nicely - the goal being to record live music broadcasts from 2MBS FM.

Unfortunately, even at 15ips the loss of quality was too great for my liking and I also found the same thing when I tried a Teac 1/4 inch half track in the role. Modulation noise, tape hiss and loss of definition ( IM distortion ?) were all too evident. Mind you, I was listening via Quad ESLs.

The only tape recorder that came close was a VHS Hi-Fi video loaned to me by a customer. That could copy an all digital CD of classical piano with negligible loss. Funny how they never caught on as audio recorders.

Consumers all seem to prefer convenience over sound quality.



.... Phil

Yes - there were several better cassette formats than compact cassette, but CC is what won.


NT

 

On Friday, 19 April 2019 19:54:13 UTC+1, pf...@aol.com wrote:

On Friday, April 19, 2019 at 1:39:13 PM UTC-4, tabby wrote:

The one I had gave the Quad II a very good run for its money. Perhaps your comments apply to some earlier model. Their downfall was the excessive voltage used on the valves, 500v on 7189A IIRC. That & the unavailability of 7189A is why they aren't a recommended buy now.


I will spare you my opinion on Quad tube stuff. And, as it happens, their equipment from start-to-finish is vastly overrated - but for a few of their ESL speakers. Operative word being 'few'.

c.f.: Blind squirrels and nuts.

But, that is why there are many flavors of ice cream, and even sherbets for the lactose-intolerant.

Peter Wieck
Melrose Park, PA

I never thought much of their transistor amps, but the II power amp was rather nice (the 22 preamp sold with them not so much) and I still wonder why I sold the ESLs.


NT

 

[Fox's Mercantile]

On 4/19/19 7:35 PM, pallison49@gmail.com wrote:
> Consumers all seem to prefer convenience over sound quality.

..mp3 is proof of that.


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

tabb...@gmail.com wrote:

** I gave up all interest in working for hi-fi importers when I heard that 90% of the work was in fixing damn cassette decks. Although I have worked on a few for regular customers, I have never owned one.

However, I did buy a Brenell RR transport fitted with "Sonic" heads from Geoff at RDS in the late 1970s. Built all the necessary electronics and had it working nicely - the goal being to record live music broadcasts from 2MBS FM.

Unfortunately, even at 15ips the loss of quality was too great for my liking and I also found the same thing when I tried a Teac 1/4 inch half track in the role. Modulation noise, tape hiss and loss of definition ( IM distortion ?) were all too evident. Mind you, I was listening via Quad ESLs.

The only tape recorder that came close was a VHS Hi-Fi video loaned to me by a customer. That could copy an all digital CD of classical piano with negligible loss. Funny how they never caught on as audio recorders.

Consumers all seem to prefer convenience over sound quality.



.... Phil

Yes - there were several better cassette formats than compact cassette,
but CC is what won.

** A massive irrelevance.

NT

** NT = Nutcase Thornton serial pest and troll



...... Phil