Re: K6100 T901

        Ok.. I pulled my transformer

        Primary : 625 turns (give or take some..lol Id say its within a percent
or two) very fine wire

        Secondary: 23 turns

        pics for your enjoyment:

        http://www.flickr.com/photos/mcandrewsnd/sets/72157627466514605/

> I heartily agree that whoever takes the time to investigate the
properties

> of the T901 transformer should post the info the the list, and
hopefully

> the list owner will save that info on the vectorlist website
archives.

>

> If I finish rebuilding my living room/stero/TV setup this weekend,
I'll

> pull the working T901 from my spare WG high voltage board and try
to

> measure the turns ratio and the resistance of both coils. I'll
post the

> info here when I get it.

>

> ___

> Ken

>

>

> On 09/02/11 18:11, litterbox99@mchsi.com wrote:

>> I can't imagine that someone hasn't done this

>> before and documented it...

>>

>> It would be very usefull information.

>> Kudos ! To someone who gives it a try.

>>

>> Todd

>>

>>

>>

>> ----- Original Message -----

>>

        From: "Ken Sumrall"<k_lists@scrapheap.net>

>> To: vectorlist@vectorlist.org

>> Sent: Friday, September 2, 2011 6:53:26 PM GMT -06:00 Central
America

>> Subject: Re: VECTOR: K6100 T901

>>

>> If the old transformer is not too burned up, you can count turns
as you

>> unwind

>> it. Sometimes only the insulation melts, leading to shorted
bad

>> transformers,

>> but easy to count the turns as you unwind it.

>>

>> However, other times the wire itself melts/breaks, and then its
harder

>> to

>> count as you unwind. If only one of the two coils is broken, you
can

>> use

>> the turn count from one coil, and the measured ratio from a
working

>> transformer

>> to figure out the turns count for the broken coil.

>>

>> Good luck if you choose to do it, and if you don&#39;t want to,
you can send

>> me

>> your burned out transformer and I&#39;ll give it a try.

>>

>> ___

>> Ken

>>

>>

>> On 09/02/11 17:40, akswanson@ntelos.net wrote:

>>> I have been contemplating rewinding it. I&#39;ll pull it
apart and see how

>>> bad. I

>>> Love the 250ma fuse mod. Im thinking of some kind of fuse
mod for this

>>> G08 im

>>> working on that keeps blowing output transistors (yes they
are the

>>> correct

>>> devices, not the 3716s). Ugh.

>>>

>>> > I&#39;ve thought about this some more, and it seems to
me this would

>>> not

>>> > be that hard to rewind yourself. You can easily measure
the turns

>>> ratio

>>> > of a working transformer with a signal generator set to
the right

>>> > frequency

>>> > and a volt meter to read the output. Or just probe the
input and

>>> output

>>> > terminals of the transformer in a working circuit,
though the load

>>> on the

>>> > transformer could affect the readings.

>>> >

>>> > Then you could estimate the number of turns on the
primary by

>>> measuring

>>> > the

>>> > resistance of the wire and it&#39;s gauge, and using a
chart that

>>> lists the

>>> > resistance/foot of the standard wire gauges.

>>> >

>>> > Winding transformers is not fun, but not hard to do.
Just time

>>> consuming.

>>> > If there is enough demand, it might be worth while to
get a batch

>>> of them

>>> > custom made.

>>> >

>>> > I know someone who sold a Scope Clock kit, and he had
the special

>>> > transformer

>>> > he needed for his design custom made. I could ask him
where he got

>>> them

>>> > made

>>> > if there is enough interest to investigate this
further.

>>> >

>>> > Is there a pent up demand for this transformer?

>>> >

>>> > ___

>>> > Ken

>>> >

>>> >> --- k_lists@scrapheap.net wrote:

>>> >>

>>> >>

>>>

        From: Ken Sumrall<k_lists@scrapheap.net>

>>> >> To: vectorlist@vectorlist.org

>>> >> Subject: Re: VECTOR: K6100 T901

>>> >> Date: Sun, 28 Aug 2011 19:33:27 -0700

>>> >>

>>> >> I searched my local archives of the vector list,
and found this

>>> post

>>> >> from July 8, 2007 from Hans O:

>>> >>

>>> >> > AH, now I remember. They&#39;re found in old
B& W raster chassis.

>>> >> > Track down an old 19V1001 or 1003 chassis.
Should be a bunch

>>> of

>>> >> > dead ones out there.

>>> >> >

>>> >> > Hans O

>>> >>

>>> >> Good luck!

>>> >>

>>> >> ___

>>> >> Ken

>>> >>

>>> >> akswanson@ntelos.net wrote:

>>> >>

>>> >>> lol..no worries.. I guessed maybe I had the
wrong part ##. I

>>> will

>>> >>> DEFINATLEY check that out!!

>>> >>>

>>> >>>

>>> >>>

>>> >>> > Oops, I just realized you&#39;re not
talking about the flyback,

>>> but

>>> >>> the

>>> >>> > smaller transformer on the HV board.

>>> >>> >

>>> >>> > Sorry, I don&#39;t know where to get a new
one of those. However,

>>> I do

>>> >>> > recommend you read the installation manual
for the

>>> replacement

>>> >>> flyback

>>> >>> > which you can find at the first link
below. It includes

>>> >>> instructions on

>>> >>> > how to add 3 fuses to the HV circuit to
protect components

>>> >>> (including

>>> >>> > T901) in the event of another failure like
the one you have.

>>> >>> >

>>> >>> > ___

>>> >>> > Ken

>>> >>> >

>>> >>> >

>>> >>> > Ken Sumrall wrote:

>>> >>> >

>>> >>> >> You can get one here:

>>> >>> >>

>>> >>> >> http://www.cinelabs.com/wg6100/

>>> >>> >>

>>> >>> >> which has link to here:

>>> >>> >>

>>> >>> >>
http://arcadeshop.com/wgxy-fb/wgxy-fb.htm

>>> >>> >>

>>> >>> >> $79, and comes with extra protection
components and a new

>>> focus

>>> >>> >> assembly.

>>> >>> >>

>>> >>> >> Note, I&#39;ve never ordered or used
one of these flybacks, I

>>> just

>>> >> remmeber

>>> >>> >> seeing it recently while searching for
other parts to bring

>>> a

>>> >>> 6100

>>> >> back

>>> >>> >> to life.

>>> >>> >>

>>> >>> >> ___

>>> >>> >> Ken

>>> >>> >>

>>> >>> >>

>>> >>> >> akswanson@ntelos.net wrote:

>>> >>> >>

>>> >>> >>> I had suspected the triple nickel
(555), and indeed it was

>>> >>> fried.

>>> >>> >>> It also took out Q905, AND T901..
I verified this by trying

>>> T901

>>> >>> in a

>>> >>> >>> known good HV unit. I got smoke,
and another blown Q905..

>>> So if

>>> >>> >>> anybody knows where I can get a
replacement T901 thatd be

>>> swell!

>>> >>> >>>

>>> >>> >>>

>>> >>> >>>

>>> >>> >>> > I&#39;m not saying that you
don&#39;t have a bad T901, but can

>>> you

>>> >>> verify

>>> >>> >>> that

>>> >>> >>> > IC901 (555 timer as a simple
oscillator) is running. A

>>> scope

>>> >>> would

>>> >>> >>> show a

>>> >>> >>> > nice square wave coming out
at pin 3. If it is stuck in

>>> the

>>> >>> high

>>> >>> >>> state,

>>> >>> >>> > it would keep Q904 and Q905
turned on constantly and

>>> that

>>> >>> would

>>> >>> >>> certainly

>>> >>> >>> > cause your problem. Of course
in this state, there would

>>> be

>>> >>> no HV

>>> >>> >>> output

>>> >>> >>> > at all. Check ZD900 for 13V
across it. ZD900 is the

>>> voltage

>>> >>> >>> regulator

>>> >>> >>> > for the 555 chip. If the
zener is partially shorted and

>>> there

>>> >>> isn&#39;t

>>> >>> >>> > enough voltage across the 555
chip, then the 555 chip

>>> output

>>> >>> might

>>> >>> >>> be

>>> >>> >>> > stuck even if there&#39;s
nothing wrong with it. If the

>>> zener is

>>> >>> >>> > open-circuit, the 555 chip
will likely have blown.

>>> >>> >>> >

>>> >>> >>> > You should remove R917 and
leave it out until you can

>>> verify

>>> >>> that

>>> >>> >>> IC901 is

>>> >>> >>> > running okay and that the
transistors Q904/905 are both

>>> >>> switching.

>>> >>> >>> To

>>> >>> >>> > functionally test Q905, you
can add a temporary 10k (to

>>> 47k)

>>> >>> >>> resistor

>>> >>> >>> > (1/2W to 1W) from +Vsupply
(+28V) to Q905 collector. If

>>> scope

>>> >>> shows

>>> >>> >>> a

>>> >>> >>> > good square wave, remove the
temporary resistor and

>>> return

>>> >>> your

>>> >>> >>> focus to

>>> >>> >>> > T901.

>>> >>> >>> > If you do not have a scope
but you have a voltmeter,

>>> connect

>>> >>> your

>>> >>> >>> meter

>>> >>> >>> > (-) to ZD900 anode or IC901
pin 1. Use the meter(+) to

>>> >>> measure

>>> >>> >>> voltage at

>>> >>> >>> > ZD900 cathode and IC901 pin
8. Both should be about 13V.

>>> >>> Measure

>>> >>> >>> IC901

>>> >>> >>> > pin 3. If it is running, it
should be around 6.5V

>>> plus/minus

>>> >>> around

>>> >>> >>> 0.5V

>>> >>> >>> > roughly. The point here is
that pin 3 should be

>>> outputting a

>>> >>> square

>>> >>> >>> wave

>>> >>> >>> > having roughly a 50% duty
cycle so the voltmeter should

>>> show

>>> >>> >>> approximately

>>> >>> >>> > one half the chip supply
voltage.

>>> >>> >>> >

>>> >>> >>> >

>>> >>> >>> > William Boucher

>>> >>> >>> > http://www.biltronix.com

>>> >>> >>> > ----- Original Message
-----

>>> >>> >>> >

>>> >>> >>>

>>> >>>

>>>

        From: akswanson@ntelos.net

>>> >>> >>> > To:
vectorlist@vectorlist.org

>>> >>> >>> > Sent: Sunday, August 28, 2011
9:20 AM

>>> >>> >>> > Subject: VECTOR: K6100
T901

>>> >>> >>> >

>>> >>> >>> >

>>> >>> >>> > One of my 6100s had a fire on
the HV board, took out

>>> R917 and

>>> >>> Q905.

>>> >>> >>> I

>>> >>> >>> > replaced those, and got smoke
again.. Comparing the

>>> >>> resistance of

>>> >>> >>> the

>>> >>> >>> > primary of T901 to a known
working T901 I get 9.5 Ohms

>>> on the

>>> >>> >>> suspected

>>> >>> >>> > bad one and 17 ohms on the
known good one. I get the

>>> feeling

>>> >>> I

>>> >>> >>> melted

>>> >>> >>> > the varnish on the wiring and
shorted them together..

>>> Does

>>> >>> anyone

>>> >>> >>> know

>>> >>> >>> > where (or have) and extra
T901? Also, Is there a

>>> secondary

>>> >>> cause,

>>> >>> >>> such

>>> >>> >>> > as a flyback failure that
would cause this kind of

>>> failure? I

>>> >>> dont

>>> >>> >>> > want to blow the dang thing
again..

>>> >>> >>> >

>>> >>> >>> >

>>> >>> >>> >

>>> >>> >>> > Andrew

>>> >>> >>> >

>>> >>> >>>

>>> >>> >>

>>> >>>

>>> >>
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>>> >>> >> chris@westnet.com

>>> >>> >>

>>> >>> >>

>>> >>> >

>>> >>>

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>>> >>> >

>>> >>>

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Received on Sun Sep 4 10:27:19 2011