does a fake LOPT even exist?

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Hi all,
I'm trying to keep an old TV alive, it's an old 14CT2306/20S from Philips  
and it's the only think that fits into a furniture space in my parent's  
house, so that will not be replaced. I'm keeping it alive for 30+ years now.
The LOPT developed some leaks in the past years but they where on the external
side so I was always able to scratch the hole zones and put some epoxy that
cured the leak. Lately it developed a nasty leak to the internal core, so
it's time to find a replacement for it.
I ordered an HR-6098 LOPT on ebay based on diemen HR equivalence and when
it arrived, I noticed that it lacks pin 1.  
On the diemen site, the HR-6098 indeed has pin 1, schematics and actual
chassis both agree that pin 1 is needed as horizontal signal going into
an LM339 comparator, so I think I can't put this transformer in place
of the original one.
The ebay seller just said that since it's stamped with the correct name,  
it must be it and I'm just not able to install it correctly :)
Is there any chance that the seller is right or my only option is asking
for a refund via PayPal?
What could be going on here? I wouldn't believe it's viable to make
fake LOPT anyway. Maybe a mis-labeled unit that was so similar to the  
rigth one?

Thanks
Frank

Re: does a fake LOPT even exist?
On Saturday, February 25, 2017 at 1:31:35 PM UTC-5, frank wrote:
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Could be a mistake, or it could be intentional.  IIRC, Diemen uses only a f
ew common case molds so a lot of their LOPTs (we call them flybacks) look a
like. A few years ago I bought some a generic transformer for an RCA and wh
at they sent was missing the G2 wire.  I called the company and they had on
e left and this one had the G2 wire.

According to Diemen, the 6098 does have an active pin 1:

http://www.hrdiemen.com/reparation/flyback/scheme/6098

I would say the wrong trans was put in the box (it did come in an H.R. box,
 no?).  Here's a pic of the actual transformer.  Does yours look like this  
print and all?

http://www.electronic-spare-parts.com/descript/h/hr_6098.htm

H.V. transformers are not difficult to make but H.R. transformers are premi
um, so it wouldn't surprise me if someone didn't try to stuff a cheap Asti  
Magnetics transformer into an H.R. box.




Re: does a fake LOPT even exist?
snipped-for-privacy@gmail.com wrote:
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That's where I checked too. The schematic of the TV clearly shows some
connections from the pin 1 to the rest of the circuit and the actual PCB
matches too.

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it looks very similar. The print is on another place, but it says HR 6098.

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Whatever... I'll try to ask for a replacement or money back. It isn't clearly
what it is supposed to be.
Best regards

Frank

Re: does a fake LOPT even exist?
wrote:

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What is a LOPT? I'm guessing it's a Picture Tube (CRT), but after
reading your post, I am not sure what you're talking about....
Please define.....


Re: does a fake LOPT even exist?
snipped-for-privacy@tubes.com wrote:

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** You could Google the term.

 LOPT = HOT = horizontal output transformer.  



....  Phil  


  


Re: does a fake LOPT even exist?
snipped-for-privacy@tubes.com wrote:
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Line OutPut Transformer. I should have called it flyback maybe

Re: does a fake LOPT even exist?
I would see if the seller can find you one that has pin 1. He simply might  
not have one and if you want this thing to work you might have no other cho
pice but to do a bit of modification.  

I used to be the King of modification, I mean I soldered a frigging ECG159  
too a Syvania deflection IC (15-43301 I think) to cure a no synch problem.  
I have retuned horizontal deflection circuits. So I could do this pretty mu
ch.  

there are a couple of things to keep n mind when you go down this path. For
 one, if all you need a a phase signal going back to a deflection IC somewh
ere, resistors are your friend. You can get that off of almost any winding.
  

And if not, if the core is not totally sealed and you can get a wire betwee
n it.  

The problem with this plan is that if it really is a negative going 55 volt
 pulse I suspect they are using it for more than synch. You might have miss
ed something on the print or who knows.  

The other problem is distance. You get this thing down here with prints I a
m sure I can make that transformer work unless it is really off. That is wh
at I did for a living for a while, and it was sort of lucrative.  

But still, plane tickets are not in the budget. I completely understand tha
t some people do not want to change their decor. I also understand that som
e people cannot stand watching an LCD screen. Many of them are the ones who
 bought plasma TVs because you are still watching a phosphor. I know LCDs h
ave improved alot of the last decade or three, and really what makes some p
eople want to krep their old TV is more like "I finally learned how to work
 the damn thing". I had that in the VCR business. Really, I would call the  
guy and say "Well unfortunately the repairs come to like a bit over the cos
t of a new one so it is probably better too just repplace it" and they woul
d come back with "Fix it, I finally learned how to program the timer on thb
is one and I am not about to start over". I shit you not.  

Anyway, back to brass tacks here. IF you can get a wire through that core,  
you can have any winding you want. I had to make one with about 400 volts o
n it to match a yoke to the wrong set, and CRT. All you appear to need is 5
5 volts. Thatis not that many turns. Just use your scope. And don't worry a
bout wire guage, most of it is really thin. Seriously. Only in big audio po
wer amps do you really need heavy guage wire.

Re: does a fake LOPT even exist?
snipped-for-privacy@gmail.com wrote:
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the world looks full of HR-6098 from various vendors.
I just opened a case on ebay, let's see what happens.

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I'm always open to modifications, but not when the right fix is so easy
like getting the right part (that's not even scarce) :)

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yes, I could get away easily with a resistive partition from another pin.
But what if the mislabeled(?) transformer isn't so close to what it should be?
The TV set is still working, so why should I try my luck?

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looks like it's a synchronization signal to display a vertical bar moving
with the electronic memory tuning. I didn't go into much details, but seems
it's not going anywhere else (and it can be removed for old sets without
digital memories).

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I know it was. I'm a poor electronic engineer that lives in a no-fix world :)
I could fix most of the old stuff, but that's not something like a real  
job nowadays.

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much simpler here: as I said, it's the only TV set that fits in the damn
box in the old piece of furniture in my parent's kitchen.  
I could never find any LCD that would fit, nor any other CRT.
I would be more than happy if I could recycle this set.

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The right replacement is available in tens of online stores. I first let
ebay deal with this mistake (as the seller just said I can't use it and  
didn't even want to check another one).

Thanks
Frank

Re: does a fake LOPT even exist?
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with the electronic memory tuning. I didn't go into much details, but seems  
it's not going anywhere else (and it can be removed for old sets without  
digital memories). "

If you can get a wire through that core you ggot it licked. I can't even count how many times I "fixed" an H-K short by just "wrapping the flytback" which gave the CRT a totally gloating heater and fixed the problem.  

You need a scope to see how much voltage you get. For a CRT filament we needed 22 volt peak to peak to get the 6.3 volts RMS, but you do not have that problem.  

The bottom line here is that you might have no other options. I dealt with that quite a bit, flybacks had all their pins but were tuned wrong or whatever, I had to pad quite a few with extra capacvirots on the HOT. (LOPT)  

I would talk to the manufacturer, but unfortunately due to the nature of the business he miogh just say "We cannot do that, we will give you a refund". Well as we know, that does not work.  

Re: does a fake LOPT even exist?
wrote:

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If you had said "Flyback", I would have known what you meant. (common
term for old CRT type TVs).

I once had a flyback on an old CRT computer monitor develop an
electrical leak. The case of this transformer (some sort of plastic
coating), had a crack in it, and it was snapping and shooting an inch
long spark..... A nice thick blob of silicone caulk over that hole
solved the problem.... (Clean the thing first with alcohol, then let the
silicone harden, before using).

If my memory is right, the B&W Tvs had around 15,000 volts and the color
Tvs had around 25,000 volts on those flybacks. That's one thing I dont
miss.... those things were known to develop leaks over time, and were
dangerous to work on. HV problems seemed to be the #1 cause of tv
failures. Accumulated dust added to the problems, so always clean off
dust.

PS. If you want to save that console cabinet TV, but modernize it,
remove the chassis and picture tube. Then find a modern flat screen tv
that will fit in the cabinet. Better picture, and less problems....

I have to admit that I miss the nice looking wooden console cabinets
those old TVs had. But an old cabinet can be reused, with a new tv
inside.

When it comes to stereos and amplifiers, I prefer the old stuff (esp the
tube stuff), but when it comes to TV sets, I'll take a modern one any
day over those old CRT sets.



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