[TechAssist] Re: CTC169BG5 Audio problem additional info

Not yet.
the unsoldering of pin 16 was to see if D.C.
leakage  was tripping the sense line.
Walter
--- al m <ampm@xxxxxxx> wrote:

> Were the outputs replaced Walter? I had one
> awhile back that had bad outputs
> and the voltage on the supply was doing the same
> thing. Replacing the
> outputs fixed the set. I think the set was
> shutting off, but I'm not sure.
> Al Marquardt
> ampm@xxxxxxx
> Al Marquardt Electronic Repair
> 206 W Main
> Girardville Pa. 17935
> ----- Original Message ----- 
> From: "walter wood" <wwood_38478@xxxxxxxxx>
> To: "Tech Assist" <techassist@xxxxxxxxxxxxx>
> Sent: Friday, July 30, 2004 4:51 PM
> Subject: [TechAssist] CTC169BG5 Audio problem
> additional info
> 
> 
> > Recap"
> > This set has a great picture, but the sound
> would
> > go off in about 5 seconds.
> > List members were generous in providing
> schematics.
> > One tech suggested opening up the DC sense line
> to
> > see if that was the problem.
> > I unsoldered pin 16 of JS1900.
> > The audio stays on longer now, but still shuts
> off.
> > There is a slight thump in the speakers at turn
> on,
> > but nothing unusual at all when the sound
> > disappears.
> > I got out my trusty Radio Shack audio signal
> tracer
> > and I have sound on pin 7 of U1901 and U1902 at
> all
> > times.
> > This can be varied with the sets volume control
> as
> > it should.
> > Pins 2 and 4 have the required +17 and -17.
> > Pin 3 shows -12.3 on the schematic.
> > there is -17 there at plug in.
> > That goes to -13 when sound is present, then
> goes
> > to app. -15 when the sound disappers.
> > The afore mentioned pin 16 JS1900 is still
> > unsoldered.
> > This might be a clue.
> > When I was testing the voltages the probe
> slopped
> > and I temporally shorted Pin 5 to 3 on U1901,
> and
> > the sound returned briefly.
> > I have to admit that I don't understand this
> > mute/DC sense circuit.
> > Anyone got any clues at this point?
> > TIA
> > Walter
> >
> > =====
> > Walter Wood
> > Future Tech Home Center
> > 2786 Hwy. 43 N.
> > Lawrenceburg Tn. 38464
> > 931-829-3337
> > Fax 931-829-4044
> > mailto:wwood_38478@xxxxxxxxx
> >
> >
>
--------------------------------------------------------------------------
> ---
> > Lost Password:
> > http://www.tech-assist.org  and select "Login
> Problems?".
> > Email Archives:
> > http://www.freelists.org/archives/techassist/
> >
> >
> 
> 
> 
>
-----------------------------------------------------------------------------
> Lost Password:
> http://www.tech-assist.org  and select "Login
> Problems?".
> Email Archives:
> http://www.freelists.org/archives/techassist/
> 


=====
Walter Wood                  
Future Tech Home Center        
2786 Hwy. 43 N.
Lawrenceburg Tn. 38464
931-829-3337
Fax 931-829-4044
mailto:wwood_38478@xxxxxxxxx

-----------------------------------------------------------------------------
Lost Password:
http://www.tech-assist.org  and select "Login Problems?".
Email Archives:
http://www.freelists.org/archives/techassist/

Other related posts: