Jeff,
This is what I have, it's originally from you hope you gave yourself
good advise...:) GL "joe"
==================================
RCA P46770CK/ PTV169PA FBT
I suggest you read the following post before proceeding to see if this
is applicable to your situation. Please let us know if it is so we can
gather this information and forward it to the appropriate personnel: We
ordered a 232191 IHVT from Union Electronics. This was for a PTK169. The
first one we received failed to work. Many hours troubleshooting time
spent and unneeded replacement parts were installed determining
something was wrong with the new flyback. (Holly at Union again verified
the part number was correct.) Another was ordered again from Union.
Again many hours of time was spent determining that this part was also
bad. This was confirmed when a known good flyback from a working set was
substituted temporarily and the set fired up and worked beautifully. A
third transformer was ordered, this time from Andrews. (Willy at Andrews
also verified we were ordering the correct part). The part from Andrews
arrived and worked just fine. All 5 transformers, the original, the one
from the working set that was used as a substitute, and all three new
flybacks had the same part number on the flyback, 2G25018 and TCE
30.0KV. All three new flybacks had the part number 232191 on the boxes.
During the course of checking the transformers against one another we
discovered that apparently the 2 from Union were MIS-LABELED AT THE
FACTORY! They appear identical on the outside with one exception: The
two original FB's and the 3rd successful FB all had a green ink splotch
about 1/2 to 3/4 inch in diameter on them, whereas the two that did not
work had no such splotch. I don't know how significant that is. We
determined that these transformers were made to be used in the direct
view chassis and were MIS-LABELED AT THE FACTORY. According to the tests
we performed here, it has to do with the way pin 6 is connected on the
direct view VS the PTV-- In the Direct View CTC169, pin 6 is the low end
of the Anode winding. In the Projection PTK169, the black wire (also
present on the Direct View flyback) is the low end of the Anode winding
and is connected to a circuit that looks like it monitors beam current
and limits peak brightness. Symptoms of the wrong FB in the Proj set:
Standby is just fine. Hit PWR: Momentary Horiz drive. 200V line only
goes up to about 100 or 120V and the 26V line goes up to about 36V, as
measured on a 'scope. If you short pin 4 of T4101 (Run regulator
feedback) to hot ground as per the official Troubleshooting manual,
R4762 (430 ohms 1W) on the HV Reg PCB (mounted on the H.O.T. heatsink)
blows the magic smoke. This HV Reg PCB is not present in the Direct View
set. How to test before installing the FB to make sure that you have the
correct one: Using the Sencore VA48, Horiz SCR output, connect ground to
pin 1 and drive to pin 11. Use your scope to adjust to 10V positive peak
pulse drive. Here's the key to the test: If you measure the anode
voltage using the wrong pin as ground/common, the voltage is too low.
The exact voltage is very sensitive to the drive voltage, so comparison
is the key. Proj FB using black wire as common on 10M DMM: 220 to
230Vdc. Proj FB using pin 6 as common on 10M DMM: 150 to 160Vdc Direct
View FB using black wire as common on 10M DMM: 150 to 160Vdc Direct View
FB using pin 6 as common on 10M DMM: 220 to 230Vdc I'm sure you see the
pattern. :'/ A cross check of the Thomson PTK169 service manual on CD vs
our paper Thomson CTC169 is inconclusive as the schematic of the PTK169
FB circuit labels the low end of the anode winding as pin 6. The PTK169
service manual lists the replacement part as 232191.
==================================
[EMAIL PROTECTED] From: [EMAIL PROTECTED]
(Intrepid�Video�Support) Date: Tue, Feb 24, 2004, 11:07pm To:
[EMAIL PROTECTED] (Tech List) Subject: [Techs] RCA P46770CK/
PTV169PA///FBT question.// Reply�to: [EMAIL PROTECTED]
(ELECTRONICS PROFESSIONALS LIST)
A little over a year ago there was a discussion regarding the flyback
for this projections set. I had ordered 232191 three times and none
worked.
I come to discover, these apparently were for direct view sets, not
Projos.. The unit I had at the time, I ended up using HV putty to seal
the hole. I have a service call on this unit about 15 months, I think
the HV leaked through my repair. Has anyone had success with this part
number lately using it on a projection unit.. I am familiar with the
notes that come with this part, but that is not an issue.. I believe
someone mentioned our friend in Mexico had been mislabeling these, or
something to that effect...

Thank you.
Jeff Dougherty
Intrepid Video TV/VCR
263 S Front St
Steelton PA 17113
fax...717-564-4952
www.intrepid-video.com www.tech-repair.net
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Joes....Electronics
�(Joe:Tech/2004)
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