Portholes on eBay

[bigaudioal]

My porthole flyback looks VERY similar to the one above. I also have not tried to put any power to mine. Glad I got that NOS replacement - just in case.

[bandersen]

Al, I think the set picture above is the same Graemere model you got from me. Here's a photo of its flyback which looks a lot better.

[bigaudioal]

I think that set is the exact same model Bob! So beautiful. You are correct, that flyback looks LOADS better. I cannot wait to have that set playing one day!!!!!!

[Down Under]

Originally Posted by cwmoser

Shipping to Australia would be quite expensive - just guessing.
That along with building a protective crate.
I'm curious, have you got a rough estimate of the cost?

No, but I'm guessing around $1000. A couple of years back I bought a Predicta Holiday on a roll away stand and that cost $700 to freight here. It was very well protected and arrived here in perfect condition. But I believe the Pirtholes are a lot heavier than Predictas.

[Down Under]

Seeing the pictures of these obviously distressed flybacks raises a question: why do they do this?

Is it just poor circuit design, underrated windings for the job, or is there more stress when metal CRTs are involved? On a humid day, there are more likely to be losses due to coronas and arcing from the metal section of the CRT. Do flybacks in sets using all glass CRTs last any longer? This might seem very far-fetched, but would a liberal slathering of RTV133 on a metal CRT reduce stress on the flyback? Food for thought...

Cheers,

Adam

[bandersen]

The few I've seen up close like the one pictured above appear to suffer from deteriorating plastic of some sort. I don't think they're burning up as much as crumbling apart.

[TV-collector]

Hi Down under!

I am a german collector who is hooked on aussi TVs.
Number #7 (early rare STC) is soon on the way.
Shipping is very expensive and a question of the distance.
Maybe that`s the reason why I am the only one in Europe who
owns australian TVs.
O.K., its the other side from our earth!
WHAT A LUCK that Australia, a partner of the Commonwealth, decided to
introduce the european CCIR standard. In this case I have no problems with them!

The 21" Kriesler console, 100km down from Sidney picked up by the shipper,
crated in a perfect wooden box was a 1600,- Euro gift to me.
(The smiley says everything!)
This price is incl. customs work, x-ray control etc. because of 9/11.

I have 2 portholes, the 12" Raytheon and a 12" Zenith.
The Raytheon had a factory installed wrong winding on the power transformer.
My transformer man has controlled it and was amused that this transformer lived longer then a week as it was new (totally burned).
The set was a self import from my last US-travel.

As an Aussi you are on the right side when you decide to rewind the
power transformers to 230 Volt.
I can give you for that the new winding numbers!
I have a 50s article (Funkschau) of a german TV repairman who revised in the 50s hundreds of US TV sets from members of the US army in Germany.

When the americans went back, he turned them back into the US standard.

You have more fun with the TVs when you allign them to CCIR because of
the bandwidth.
I don`t think that you are able to produce 60 Hz to run with the US vertical frequencies.
Do you have a NTSC converter from an old US-vcr?

Are you on the way to do this work completly?

These older HV transformers can be rewinded, missing knobs are bigger problems.
American schematics are really good, there is no way to do them better.

I heard that 12" tubes are often down with there emission/gassy and not so easy
to find than 10" tubes.
Please correct me if I am wrong.

Happy week-end,

TV-Collector

[old_coot88]

Originally Posted by TV-collector

...These older HV transformers can be rewinded...

Could you elucidate with a little more details and particulars on that?
Thanks

[M3-SRT8]

Larry Fine says, damn the flybacks, full speed ahead.

[TV-collector]

Yes, I like to do it:
-you need a winding machine or you build your own with a low voltage
battery powered drill. Importent is a counter.
-you need some special hoses for the thin wires
-you need a special kind of paper which looks like thin cardboard

The "special stuff" I am talking about is not common to me in english.
I have to find a translation.
My elderly friend workes his hole life in a transformer/electrical motor repair
and construction company.
Nothing he couldn`t fix!

"Modern" HV transformers which are glued like the junk in my Predicta
is not worth to rewind, because you don`t get the glue off to count the windings.

All over the world we are cooking with water, this means that we can
interchange all kind of transformers as far they are similiar constructed.

The deflection angle and the high voltage has to be the same.
Then you have to control what kind of other windins and tabs you have.

In the case of my Predicta Barber Pol I decided to kick out the HV transformer,
which went down south including his glue and the 5 wire deflection yoke
and rebuild it with a Philips system.

If only the HV coil is destroyed (inside or only at one of the ends?)
it can be easy changed.

Since some weeks I work out with the help of my friend how to do
an easy transformer repair/winding change.

I have a lot of japanese vintage radios and TVs, most of my US TVs are rewinded.
My friend did it, but now because of his age he didn`t like to do it anymore.

Now I have to learn from him.

TV-Collector

[TV-collector]

before you fire up an old TV which spended its life for a long time in a wet cellar you have to take the HV transformer out from the chassis and dry it in your oven with about 40-45 Degrees Celsius!
Allow to rest for about 30 minutes!

Do this when your wife is out for shopping! You know what I mean?

[Down Under]

That's very interesting! I wondered about being able to substitue flybacks. The flybacks in the two Predicas I've restored so far are in perfect working order, so no need to replace. I did follow Bob's tip and recoat them with RTV133, a high dielectric strength silicone. Great stuff, and easy to produce a tidy appearance if you wet your fingers with denatured alcohol before smoothing the coating over with your fingers before it dries.

A friend of mine in the UK is able to wind transformers since he is designing and planning to market high end tube amplifiers. He is not happy with the existing range of audio output transformers, so he is winding his own. He uses CNC control of his winder.

It's also interesting to see how the Porthole flybacks are disintegrating... almost as if they used the same Tenite plastic as used on the 21 inch Predictas! Thanks to all who posted pictures.

I have not bothered about converting the power transformers to the AU standard of 240 volts, I just use a separate stepdown isolation transformer. Although I may change my mind later, as my UK friend has offered to wind some for me.

Video signal is from a cheap DVD player, that is able to produce both PAL and NTSC. I put up a post about it a few weeks back. The picture would bounce slightly with the NTSC signal, so I thought I must have had a fault. It turns out that resetting the DVD player to produce a PAL signal and readjusting the vertical hold fixed my problem. US TVs are extremely forgiving in this regard!

The Australian STC set you have would be very nice indeed, and quite rare. Other AU sets that you might want to collect would include brands such as AWA, HMV, Astor and PYE. The PYE Pedigree is a great set, but it comes down to personal taste. I would love to have one, but limited floor space means that I probably will not. The later versions used transistors, so you may need to do your research very carefully if you buy one.

As to doing things when the wife is not home, I understand all too well. That is when I use the stove to heat up capacitor cans for restuffing

Cheers and happy collecting,

Adam