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 Kriesler 11-60 refurb part 1.
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 Return to top of page · Post #: 1 · Written at 8:40:58 AM on 14 June 2020.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 883

I saw this 11-60 on ebay and bought it.
It looked pretty complete but with a few obvious problems to fix.

The ebay ad had no utter BS in it unlike some of the other sellers.
I like sellers that tell the truth, "does not work, will cut plug off".

So I received the set and carried out a tear down and survey to see how much trouble I was in.
Lots as usual.


Fred.

Kriesler 11-60 Refurb - Part 1


 
 Return to top of page · Post #: 2 · Written at 11:13:50 AM on 14 June 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1912

Ah yes Fred, another reflex set!

I was reading the chapter on Reflex in the 1955 Radiotron Designers Handbook. Looks like it was invented here and we were the only country to make radios using that principle.

It was also interesting to read specs for components, esp. electrolytics. Tolerance for capacitance is listed as -10%, +250% !

Appalling leakage was accepted for paper caps. If you were a designer in those days it paid to know this and be careful where you used them.


 
 Return to top of page · Post #: 3 · Written at 2:26:51 PM on 14 June 2020.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6354

Document uploaded.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 4 · Written at 5:38:12 PM on 14 June 2020.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1381

I think I have one of those radios, but I'll need to check. There were so many different Kriesler models that all looked the same.

In any case, mine wasn't chewed up or damaged, I'm pretty sure it was a nice easy job.

Good luck Fred in fixing yours. Smile


 
 Return to top of page · Post #: 5 · Written at 7:09:06 PM on 14 June 2020.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6354

The good thing about these late model Krieslers is that every antique shop in Australia has at least ten of them sitting on a shelf. They are a dime a dozen so getting spare parts shouldn't be a problem.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 6 · Written at 10:13:29 PM on 14 June 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4351

I have made the statement frequently that some thing like two in about 8 to 10 (fixed heaps) might have a good output transformer. We had a Radio Club fix-it day there were three there; same case, stopped there. Strike a 9V (EP 522battery across the primary of the OP transformer, that will indicate if speaker & transformer are alive.


 
 Return to top of page · Post #: 7 · Written at 9:30:32 AM on 15 June 2020.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 883

Hi Marc, when I look at the gauge of wire used and the un-hygenic way the trannys were wound it is amazing any OPT of that era is intact.

Even in the 1960's when I was winding transformers, in the middle of summer there would be beads of sweat dropping dropping into the winding area and sweaty hands handling the wire reels and wire ends.
Not so much a problem with thick wire gauges, poly coatings and varnish dip, oven baked windings.

Radio windings tended to be tiny gauges, enamel wire and layer wound with warm wax insulation and paper.
A drop of sweat into that means a green growth through the enamel and copper chewed through quick smart!

I had experiance with a local winding factory in Sydney where I advocated dropping the enamel wire and wax layer winding and introducing scramble wind with poly coat wires onto moulded formers. The owner could not see how scramble winding without interlayer insulation was possible. ( The wires will short out!) I walked away. My guitar amps had scramble wound poly wire on PT's and OPT's, varnish as you go and oven bake and I never had a failure. I knew what I was talking about. I also wound about 1kazillion rotors, field coils and control transformers for power generators all scramble wound and bashed down with a hammer. No failures.

In that local winding factory they had production winders with multiple core windings, wire spools, sheets of paper, all feeding into a cog wheel and cam finger feed nightmare apparatus. If you sneezed there would be wire and paper all over the place!
I could not cope. They went out of buisness a year later anyway. I just kept bobbin winding scramble with a 2kv primary to secondary paper or divided bobbin where ever I was working and at home in my own buisness.

For the radio projects, now I just have a motor driven spindle with a counter, a wooden trestle with a stick to hold the spool of wire and a glove to feed and tension the wire. I have a bunch of left over polywire from my last workplace and just scramble on whatever I think will work. I varnish as I go or dip the lot later in whatever modern paint/varnish is handy.

Fred.


 
 Return to top of page · Post #: 8 · Written at 9:53:51 AM on 15 June 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4351

The Americans sell bobbins for them. A guy in the Radio Club here was winding stuff & has set up a Lathe with a counter to do it.

His experience & mine is that you do not use the old winding wire. The coating is inferior an will now not tolerate winding. I have the specs for the old power transformers & they (even in 1937) were built to a tight standard & that's why many survive.

I repaired an STC coil recently after putting a KV on it revealed the break. This was, after I was lucky enough to be able to repair the breaks, coated with an electrical insulation spray (Mar). This I had also used on a Men's Shed Welder where the top windings looked a bit dodgy.

Elantas (Italy) "Elmotherm VA42 Spray" I got this from a rewinder. There is a CRC one but we stopped using it due to constant issues getting it all out of the can.

There is a fascinating video on the WEB of the Chinese automation making & assembling electric motors

Marc


 
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