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Trevor Wilson[_4_] Trevor Wilson[_4_] is offline
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Default Is there any way to test a STK463 Audio Amp chip?

On 26/04/2019 4:09 am, Bill Martin wrote:
On 4/19/19 3:23 AM, Trevor Wilson wrote:
On 19/04/2019 7:21 pm, 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.


Where does the model 2230 fall in this lineup? I still have one of
those, bought in about 1970, I think...still worked last time I powered
it on...several years ago.


**The 2230 is old school Marantz. Very nicely laid out, easy to service
and TO3 output devices. Should last a very, very long time. The smaller
receivers of the time used plastic pack output devices and were
significantly less reliable than those (like the 2230) that employed TO3
output devices.

--
Trevor Wilson
www.rageaudio.com.au

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