Bose Wave Radio loud AC hum

[flye...@yahoo.com]

My 1994 Bose Wave Radio has a VERY loud AC hum from the speakers, no
other sound. All displays are fine; display will show stations tuned
to, but no signal comes through. I checked the main filter capacitor
(10,000 mfd, 10V) and it seems to be OK.

Help!

Also, Where can I get a schematic of this radio?

[nospam]

HI.

I doubt such a large cap without excessive heat would fail, have you
checked other smaller caps in the PSU with an ESR meter ?

[Arfa Daily]

<flye...@yahoo.com> wrote in message
news:b76ff85a-a9e3-4b55...@a17g2000prm.googlegroups.com...

Mail me off-group using the address that I posted this from, with the six
digit number from the main board, and I should be able to find you a set of
schematics. Alternatively, send me a decent digital image of the main board.
There are many different variants of chassis fitted to Wave Radios, but I
have schematics to cover most of them if not exactly, then close enough to
make no odds.

Arfa

[Andy Cuffe]

If that's the version that has a small vertical daughter board near
the power transformer, then the problem is caused by leaking caps.
Bose used a bad batch of caps in their early Wave radios. Every
single one of those miniature electrolytics (and any others that are
the same brand) will have to be replaced. Don't forget the ones on
the display board, and the daughter board. You'll also have to
thoroughly clean the entire circuit board which has a film of
conductive electrolyte all over it.
Andy Cuffe

acu...@gmail.com

[BEN]

responding to
http://www.electrondepot.com/repair/bose-wave-radio-loud-ac-hum-9955-.htm ,
BEN wrote:

I am really surprised A BOSE radio is supposed to be top quality. I do not
think that BOSE corp will give you a diagram . I have worked on radios. The
older ones that used discrete components and could be restored.
I do not think the bose is repairable at the component level. bose will
probably sell you the innards. modern solid state radios are not easily
repaired or diagnostic tests done on them . mainly because they use special
integrated circuits.
I would contact BOSE and see if they will replace the innerds.. or
the entire radio.

To trouble shoot that set you would need the equipment to signal trace the
circuit on your set... if the power supply went bad and applied the wrong
voltage to the integrated circuits are probably shot..
GoodLuck
ben

[rev.11...@gmail.com]

On Wednesday, June 11, 2014 8:18:03 PM UTC-7, BEN wrote:
> responding to
>
> http://www.electrondepot.com/repair/bose-wave-radio-loud-ac-hum-9955-.htm ,
>
> BEN wrote:
>

> > flyer44er wrote (On 11/19/08) :
>


* http://www.electrondepot.com * is just one of the various forum/newsgroup archive websites that can cause this responding to really OLD posts thing, not just Google Groups.

[jurb...@gmail.com]

You really should look at the datrsof the posts. But I will respond for the hell of it. I got one.

I looked at it and there is not much about the output stage, FM or whatever, but there is a bunch of stages of OP AMPs in there that must have no other purpose but to do some really fine EQ. I mean stage after sdtage, combined OP AMPs in different stages.

This is all obviously to as accurately as possibly counteract frequncy response variables and phase shift in their particular speaker system. that's why you can't really dupolicate their EQ for the 901s with a regular ten band. You might get close, it will sound good, but not that good.

Eliminating the phase shift is important in keeping those peaks and valleys out of the frequency response curve, and though they do not do a perfect job, they at least make it sound pleasing.

IIRC, there are alot of unmarked components on that print. Some are marked, in fact I belive that in the EQ section they are marked. But look at the configuration of the amps, it is a rat's nest. This EQ system was obviously designed by instrumentation engineers. Someone capable. It is so fucking precise it is ridiculous. Of course we canot prove that becaue what, get a calibrated mic out there ? It is meant to match THEIR speakers.

The old Boses had a woofer on one side with a smaller but matched in higher freqs on the left. It used a longish cavity through the back of the cabinet to make a bass reflex system. Later models used two woofers and had the vent or whatever out the back. Sounds ghood but I have no idea which is better. I actaully have heard both, but they were years apart and in totally different environbments so ther eis no way to compare.

Watch the dates here. Nobody should say never respond to an old post, becaue if YOU had one to fix or whatever, what the hell ? Sometimes you do find a print from an old ass source at a university or something.

But trying to help anyone gone for a long time just, technically, spams the group. Unintentionally of course but the end result is the same.

But it gave me some rant time :-)

You should look it up, see the print for that MF. That EQ circuitis out of this world.

[jurb...@gmail.com]

>"* http://www.electrondepot.com * is just one of the various forum/newsgroup archive websites that can cause this responding to really OLD posts thing, not just Google Groups. "

AHA !

So we need a constant thing at the top. Didn't Sam used to do something like that ? Keep posting stuff and links to repairfaq.org and all that ?

Hmmmm

[dave]

Thunderbird sorts by date and time, latest at the top. I don't organize
by threads. Strictly chrono.

[ryan...@gmail.com]

Check the speakers when you power it up. See if either on of them draw inward to outward. If so the main amplifier chip has failed. This will also give a loud 60hz hum. Bose will not sell you the chip but I found a youtube video of such a fix and he mentioned where he got it

[jurb...@gmail.com]

Do you realize the original question is from seven years ago ?

Do you realize someone did the same shit a little over a year ago ?

[elvil...@gmail.com]

[avag...@gmail.com]

BBBBBBBBBBBBBBBZZZZZZZZZZZZZZZZZHHHHHHMMMMMMMMMMMMMMMMMMpoppopopBBBBBBBBBBZZZZZZZZZ

https://www.google.com/search?site=imghp&tbm=isch&source=hp&biw=1216&bih=612&q=1994+Bose+Wave+Radio+SCHEMATIC&oq=1994+Bose+Wave+Radio+SCHEMATIC&gs_l=img.12...3594.8779.0.12860.12.2.0.10.0.0.264.264.2-1.1.0....0...1ac.1.64.img..1.0.0.0.Qpu5isZdjyI

POPZICK _____________

[Phoena Greene]

<elvil...@gmail.com> wrote in message
news:4043cc24-c344-4d83...@googlegroups.com...

Sure the hum is coming from the radio or is Raeanne sitting next to the
radio with a black dick in her mouth?

[elvil...@gmail.com]

On Wednesday, November 19, 2008 at 2:32:45 PM UTC-4, flye...@yahoo.com wrote: