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-   -   Rare blaupunkt 3 in 1. Sevilla 7555 / 7557 (https://www.vintage-radio.net/forum/showthread.php?t=196425)

Phantomrose1999 30th Nov 2022 11:21 am

Rare blaupunkt 3 in 1. Sevilla 7555 / 7557
 
2 Attachment(s)
Super rare and in original condition. The TV has limited vertical deflection. Any pointers on where the prob may be ? First time fired up in several decades.

I am familiar fixing valve radios and tape decks and know about the EHT 16kv supply in these, which thankfully is working.

https://youtu.be/OMIxiRdEUyY

Phantomrose1999 30th Nov 2022 2:08 pm

Re: Rare blaupunkt 3 in 1. Sevilla 7555 / 7557
 
It’s actually called a Arkona 21 7875 !

Phantomrose1999 30th Nov 2022 3:25 pm

Re: Rare blaupunkt 3 in 1. Sevilla 7555 / 7557
 
1 Attachment(s)
Well I found the schematic and the vertical driver

Schematic attached.

Any idea what voltages the caps are in this circuit pls ?

Can’t get to the set until back home and then I won’t be near a spare parts shop

German Dalek 30th Nov 2022 4:09 pm

Re: Rare blaupunkt 3 in 1. Sevilla 7555 / 7557
 
Hi,
Congrats!
You have to swap all the silver shining and brown WIMA caps.
The silver shining ones have on both sides brown ends. There is a kind of
clear foil laminated over them (Values: 1000pF - ~ 0,25µF).
Best will be, if you send us a clean picture.
I shall help you with a complete manual for this TV set, it´s not only
the schematic.
I scan for free - but it takes a little time.>:(
I use mostly 1000 VDC caps, you have to order caps anyway.
The modern ones are smaller than the old ones, so no problem.
The Booster cap has to be of the finest quality.

BE HAPPY, the line output transformer (HV) works fine!!!!!!!!!!!!!!!!!!!:thumbsup:

Btw., I have here in Germany a big collection of the first Australian TV sets,
AWA, Astor, Airzone, Healing, Kriesler, STC, Electrosound-SABA.

Maybe you can help me with some mouldings for the 17" STC.

Because of the Australian safety laws there has to be a special transformer for the TV inside.
It has to be a 1958 model (with AW 53-80) or ´59 (with AW 53-88), with contrast automatic and tuning eye for the TV set.
Mostly the controls don`t like to turn anymore - something for WD-40 service.
Don`t overturn when using a plyer!!!!!

Good luck!
German Dalek:angry:

P.S. It has to be ARKANSAS (thats what I read) and because of the size! Sevilla is the name of the TV when sold
as a table set, only.

Phantomrose1999 30th Nov 2022 4:39 pm

Re: Rare blaupunkt 3 in 1. Sevilla 7555 / 7557
 
Hi Marc,

Can’t get 1k caps easily, local Jaycar has 630v caps which I use in all my Grundig sets. Will try these. The voltage to the vertical driver is 160v DC. The valve is a PCL82

I noticed on the schematic the tv chassis runs straight off the mains. All the heaters in the tubes are in series and connected to the mains ! I could not see an isolation transformer but will keep looking. If there using one I will fit one.

Yes I am very happy the EHT supply and tube is working.

Not many old B&W TV’s around these days. Either scrapped or on sheds hidden.

David

German Dalek 1st Dec 2022 7:02 am

Re: Rare blaupunkt 3 in 1. Sevilla 7555 / 7557
 
Hi David,
I should try to use all caps in the "suburban" of the LOPT with 1000 VDC.
Even the caps at the vertical output will work fine forever with 1000 VDC.
If a lower voltage is given on the original caps, you are fine with 630 VDC.

With the worse cap market of today, it is a luxury to place 1000 VDC caps all over.

Please realize, that during the warm-up the valves don´t take power, but the
valveless power supply offers a higher voltage (not regulated).


Regards,
German Dalek:angry:

P.S. Thanks to call me MARC, but I am still alive and was never a musician.
https://www.youtube.com/watch?v=LAVkRlX96Os

Maarten 2nd Dec 2022 2:05 pm

Re: Rare blaupunkt 3 in 1. Sevilla 7555 / 7557
 
Quote:

Originally Posted by Phantomrose1999 (Post 1517699)
Hi Marc,

Can’t get 1k caps easily, local Jaycar has 630v caps which I use in all my Grundig sets. Will try these. The voltage to the vertical driver is 160v DC. The valve is a PCL82

630V caps will usually be MKT (polyester foil) and not suitable for pulses or large AC signals (or across the mains for that matter). You'll have to use MKP or KP/MKP (polypropylene foil or film/foil) for those positions, especially the booster capacitor. For across the mains, any X2 rated type will be okay, preferrably also MKP.


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