More on the TN50X81 and parts status from Toshiba.
 

Others wondered if I had checked vertical and horizontal pulses and I
did see them at the convergence board. Same with clock, data and I2C
buses.

Like I said, I do get 2 good signals out of module prior to the
STK392-110 (desoldered at this moment), other 4 has bad signals or
flatlined.

I tried to adjust by playing with convergence in service mode, and
everything responded to remote but the signals on scope did not change
at all. I have feeling it is the T7K64 IC or four of PCM56PL DACs are
the problem.

In mean time we sent off request for parts numbers and prices and
Toshiba responded back:

QH001 (T7K64) available and quoted $64.78.

PCM56PL (DAC, DIP package, I needed four if I must.) 48.56 each.
YIKES!

Convergence generator module, *DING!* NLA.

For this? On a not too old TOSHIBA 1999 Projector with PERFECT CRTs?
I can get new parts from either samsung (more than 3 to 5 years old)
and RCA to keep old projectors (PTK195) going.

I have a feeling this have to do with the T7K64 IC is partially
failed. Your Opinions?

I have to make estimate shortly that I have done much of
troubleshooting and narrowed down to few possible problems.

By the way: Toshiba, THANK VERY MUCH FOR 200+ settings to record on 4
pages paper before I zapped the main EEPROM. Took long time, either
Samsung or RCA is already done in minutes with paper and chipper
checker or by hand. The convergence's EEPROM data isn't resettable
(to defaults) via menu far as I can determine.

BTW, thanks for the service manual download site, this helped!

Cheers, Wizard

The convergence eeprom is resettable via the convergence adjust menu.
I forget the exact sequence, but it is possible. It is not accessable
from the regular service menu.

On 20 Jun 2005 20:40:07 -0700, wrote:

The convergence eeprom is resettable via the convergence adjust menu.
I forget the exact sequence, but it is possible. It is not accessable
from the regular service menu.


Well, anybody with schematic for TN50X81 or similar chassis (TAC9960
or so) have the steps for resetting convergence eeprom data?

Downloaded service manual has several pages missing (intentionally?)
and the nearest service manual belongs to competitor's which my boss
is very relucently to contact. I'm not sure if Jack is going to
contact Toshiba for details that I need.

Yes, I work for a good shop by the way just that we don't service
Toshiba that often. Our shop majors in RCA, Philips, JVC, Citizen,
several models as well.

I need the info so I can fully trouble shoot and give good estimate on
this projector tv on that type of convergence problem using expensive
ICs. The toshiba's convergence module is NLA but parts within are
available.

Cheers, Wizard