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alitonto
 
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That will do me.
Great to have you on board,thanks again Frank.
From A.T.


Franc Zabkar wrote:
On 16 May 2005 05:20:33 -0700, "alitonto" put
finger to keyboard and composed:

Hello Frank,
That's the direction I was thinking but wasn't sure if anything in
particular needed to be observed. For example the schematics I

obtained
from DSE, thnks for your previous reply, indicate that the volts to

the
base of the HOT needs to be 0.34; therefore would I be correct in
thinking that the existing circuit board will produce that if I

select
a close enough match for the driver transformer?
Cheers
A.T.


AFAICS, any 12V HDT that is designed to drive an NPN transistor

should
be suitable. That's just about all of them. One caveat may be that
some HOTs have a lower hfe than others, which would mean they would
require more base current. A symptom of low drive would be a hot HOT.
Just to be safe, I'd run the set for a minute or so and then check

the
HOT temperature.

Franc Zabkar wrote:
On 15 May 2005 06:15:10 -0700, "alitonto"

put
finger to keyboard and composed:

I have Digitor 12 volt TV Model G7200 year 1993 from Dick Smith
Electronics for which the H.D.Transformer is no longer available

from
spare parts. (Checked with DSE).
I am thinking what specs to look for if I was to find a spare

part
in
my parts box.
Would this be possible at all?
It drives the HOT which is a BU407 and the chip on the board is

an
LA7680 where pin 27 supplies the signal.
Any expertize here will be welcome.
Thks
A.T.

Try adapting a transformer from a current model 12V TV. I would
imagine they would be mechanically different but electrically

similar
(same B+, same frequency, similar output).


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.



- Franc Zabkar
--
Please remove one 's' from my address when replying by email.