OK...I have been working on TV's for the last 25 years or so and I do it as
a hobby. I know what to touch and what not to touch when servicing TV's.
Now...the problem I am having is this...I do not have any secondary voltages
whatsoever. Which means no 15V stand-by or 140V B+. The main problem I have
is that I don't have a schematic. I have a CTC169JS6 schematic which has
some of the power supply circuitry but isn't the same. The chopper circuit
is working , but the 10 us pulse that is needed for pin 2 for the PWM isn't
there. Where is this pulse generated from? Does anyone here have a schematic
of this power supply that I can get a e-copy of??? Thanks so much for any
more help or assistance you can provide.

Mac


"Alan Harriman" wrote in message
...
On Mon, 13 Dec 2004 16:04:12 -0600, "Rocker" wrote:

Hello,
I'm working on a RCA RPTV, Chassis #PT169PGA. The problem is that it is
completely dead. I haven't had much experience with this chassis before,
so
I'm asking for some assistance in troubleshooting it. I do not have a
schematic for this chassis. The problem that I am having is that I do
not
have any secondary voltages at all, including no B+. I have the main
chassis board removed from the cabinet and I also have the HV lead
disconnected from the HV splitter and it is covered up in a paper towel
tube
so I won't get zapped with 30KV. Will I be able to troubleshoot the
power
supply of this TV without it being connected to the other connecting
boards??? I do have it connected to the external power supply board too.
Anyone have any suggestions or ideas on where to start looking for
problems??

Thanks!

That's probably the most common television chassis ever produced. (At
least in
my area) You should have 140V and 15V in standby, even before the set's
powered
up. If it's missing, or the wrong voltage, that will need to be corrected
first.
Also, make sure the H.O.T is not shorted. Once the standby voltages are
stabilized, only then should further troubleshooting be attempted.

Alan Harriman