ScuzzBlog: Diaries March 2021
Entry 24th March 2021: Post 1: Amiga 4000/40 - Bad capacitors - Everywhere.
Amiga 4000/40 - Bad capacitors - Everywhere.
Following on from yesterday with the A4000/40 I spent some time
mapping out the capacitor locations on the motherboard. I was a
little perplexed over not taking some pics of the capacitors just
below the hard drive bay. So I set too.
HORROR !!!!!!!!!
I discovered where the missing capacitor had come from. It was
C318 which was the partner of C317 which was leaking badly. I
decided to remove the other which literally fell off. I cleaned
up with alcohol as best I could.
I discovered that both these capacitors were linked to audio pins
on the serial interface. I researched a bit and found there to be
no support for sound on the serial. Not a biggy then.
What is interesting is that you may recall I said I used this
computer extensively on the internet to do my group mail. I had
to copy over my YAM folder the other night which took like an age.
There are thousands and thousands of messages in the folder. To
get online I used a US Robotics modem which connected to the
serial port. How odd is that. Must have burnt the things out with
all my nattering online.
I put her back together and she was still working fine. But I sense
I may have lost the serial and the parallel port. Never mind. So
now in addition to the keyboard I don't have printer and modem.
I was then putting the images together for this blog and discovered
ooze seeping out from a capacitor by the audio socket. C433. So I
removed the Picasso and the thing again just fell off. It was all
covered in a light brown gunge. I couldn't shift the debris from
the motherboard.
Anyhoo that is three capacitors removed with the loss of the serial,
parallel, keyboard and now audio. So was she working still. She
did boot perfectly and I was able to joy at my screen saver that
I use of Clara Veiga. Phew ! That was a close call. I starting to
wonder how many capacitors I would have to remove before she stopped
working completely.
I have to say I feel like I'm eating a bit of humble pie here having
bragged all these years about not having capacitor issues. This
A4000/40 is an oddity though. Cus the board was purchased from the
States refurbished, and the guy had applied a thick lacquer across
the board. It's that coating that appears to be bubbling. It is
particularly bad around the battery.
Saying all that it has changed my view of things. There certainly
is a capacitor issue and I have just experienced my first session.
Told you I would be spending another night with Paris. It is
officially springtime so Paris in the springtime. Cool. Hope you
are not offended by my backdrop. Sorry about that.
Amiga 4000/40 - Bad capacitors - Everywhere.
PHEW !!! Thank goodness Clara Veiga is
still there. Life just wouldn't be
worth living without her. Happy days.
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