Date: Sat, 27 May 2000 07:34:02 -0400
Reply-To: McComas_Glenn <mccomas@SHORE.INTERCOM.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: McComas_Glenn <mccomas@SHORE.INTERCOM.NET>
Subject: Blaupunkt amplifier blowing fuzes
John --
My 2¢ worth from several experiences with 'antique' vacuum tube
electronics:
Sounds like a capacitor in the power supply section may have gone bad.
This can create a path to ground (earth) where one did not exist
before, so that while the unit works briefly, the resistors in the
power section are heating up (well above design value) and the current
draw is large (again relative to design value).
If you are lucky enough to get a schematic for the amplifier, that
will make it easier to identify the power section, as you already
know. Finding suitable repair parts can be a bit of a quest also,
since they have to fit in a given space. Nobody is generally
optimistic about replacing parts without knowing the 'why' but......
you could try replacing the capacitors and rectifiers near the area
where you detect heating. This can mean searching the
sites/catalogues of a number of electronics surplus houses..... akin
to finding parts for an old VW.
Hopefully someone more knowledgeable in electronics will respond to
your post, and maybe Darrell midwesty@midwest.net will have
something to say? He fixes Vanagon ECUs and should have the
instruments to begin a checkout procedure. Choosing someone well
qualified and budgeting for some diagnostic time should put you on the
right path.....
Best of luck!
Glenn
Queenstown, MD
================REFERENCE===============
Date: Fri, 26 May 2000 13:54:59 -0700
From: John Clemens <jbclem@EARTHLINK.NET>
Subject: Blaupunkt amplifier blowing fuzes
My 1983 Westphalia has been musically well serviced for years by a =
Blaupunkt BPA-260 amplifier
(60W per channel-2 channels). Along with a Blaupunkt Tucson tuner I =
have very good reception and the nice crisp Blaupunkt sound. Last
week =
the fuze to the amplifier starting blowing everytime I turned the
radio =
on(the amp is triggered on by 12v from the tuner...the fuze is on the
=
other power lead to the amplifier). I've measured a current of 32
amps =
going to the amplifier which is way abnormal and making it heat up and
=
after a few minutes blowing the fuze(15 amp fuze blows right away, 25
=
amp fuze takes a little longer). Looking inside at the circuit board
I =
don't seen any sign of a hot spot, no blackened areas, no obvious =
shorts. There is a section that is heating up more than the other =
sections.
Is there someone on the list who knows enough to help me troubleshoot
=
this. I'm not sure I can get a schematic because the amp is probably
10 =
years old, but I can try the Blaupunkt web site. Or is there someone
=
who does inexpensive repairs of this type. I suspect there is just
one =
component that is bad, and since the fault is so obvious, a
knowlegeable =
person would find it quickly.
This is always the dillema in these days of throwaway electronics.
The =
electronic repair shops have minimum rates that often force a person =
into buying a replacement instead of repairing, but when you have =
something of good quality that just happens to be old), you inevitably
=
end up buying something that costs twice as much and is half as good.
=20