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 White Astor Mickey KL
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 Return to top of page · Post #: 1 · Written at 3:39:47 PM on 18 April 2022.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1773

I acquired this set a few weeks back not knowing it's condition I didn't pay much for it.
I pulled it apart on the weekend and discovered cracks and some holes in the case but I will put that aside and discuss the previous owners mastery of using fencing wire lol. Instead of placing a new electro under the chassis he decided to remove the original can and solder ( quite well I will admit) a fairly robust piece of fencing wire to the side of the transformer and wrap it around an axial 33μF electrolytic suspending it in air above the original hole. Why oh why oh why lol.

I removed what I could of his handwork and installed a terminal strip under the chassis which improved things out of sight.

Next thing I need to do is replace the open circuit oscillator coil and I believe we might have a working radio. The guy spent the money on good quality parts but could not spend the time and thought on doing a neater Job. Will try and send photos.


 
 Return to top of page · Post #: 2 · Written at 4:17:12 PM on 18 April 2022.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 1065

Perhaps it was a shed radio or to keep the cows happy in the dairy, in which case the finer points of restoration weren't foremost in his mind. Especially since the case isn't the best.


 
 Return to top of page · Post #: 3 · Written at 5:09:16 PM on 18 April 2022.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1773

Not to mention a 16μF electro measuring at 45μF .


 
 Return to top of page · Post #: 4 · Written at 6:39:24 PM on 18 April 2022.
Johnny's avatar
 Location: Hobart, TAS
 Member since 31 July 2016
 Member #: 1959
 Postcount: 486

Carl, Capacitance meters unless especially designed for high and low values, either normal air or whatever dielectric let alone electrolytics which are even more variable. Are not accurate.
A bit like automobile fuel gauges.
E=enough, or E=empty.
Regards, JJ


 
 Return to top of page · Post #: 5 · Written at 8:06:07 PM on 18 April 2022.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1643

Fencing wire, that's funny and so Australian.

I look forward to the photos.


 
 Return to top of page · Post #: 6 · Written at 6:52:22 PM on 20 April 2022.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1773

I would love to send photos of the fencing wire mod but I got too excited about fixing it.
And Johny I used the same multimeter to measure the new electro and it was absolutely spot on.


 
 Return to top of page · Post #: 7 · Written at 8:02:42 AM on 9 May 2022.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1773

Well I obtained a oscillator coil for this baby and it shows continuity I nearly had to use Tin snips to get it out though.


 
 Return to top of page · Post #: 8 · Written at 9:26:44 AM on 9 May 2022.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4701

It is notable that the old red Ducons and others had a wild tolerance range which could be in the range of + 40% or worse.

If it was not for fencing wire this country would fall apart to a greater extent. This is a farm if you need some.

One of the things missing if people want cabinet bits is a photo of the set; Even if its not that one. I am not going through my stack of unmarked sets to find numbers, when a visual scan is quicker.

That may have been a quick fix at milking time?

Cleaning out the shearing shed as its needed to shear sheep after 40 years running cattle. Its amazing what one can find as it was a storage facility kitchen Laundry & shower, while the new house got built. Shearing shed has hot water & a fixed shower and lots of valves I don't own.

Old fashioned dressing table available, has a mirror if you need something you can reflect on.

Marc


 
 Return to top of page · Post #: 9 · Written at 12:39:18 PM on 11 May 2022.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1773

What I need to ask is does the screw come all the way out of the coil and does it matter if it does.


 
 Return to top of page · Post #: 10 · Written at 1:14:13 PM on 11 May 2022.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4701

Bit of a strange question. If the oscillator coil was built with a threaded brass rod with a lump of ferrite bonded to one end of it; then its likely the padder. That will, in most cases, remove pointy end last through the base.

Should that slug be missing, & I have had one that was and ended up making a new one for it. Things like band-spread cannot be adjusted. The BC oscillator padder (unless otherwise advised) is normally set at 600kHz. RF & IF generally have them for coupling.

Marc


 
 Return to top of page · Post #: 11 · Written at 7:52:21 PM on 11 May 2022.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 1018

Marc and Carl, yep, the oscillator coil in my KL has a ferrite slug on that brass threaded thing sticking up from the chassis.
That is used to set the IF frequency at the lower end of the dial after the tuning coil is trimmed to get the stations in the correct spot via the dial pointer.
I trimmed the IF frequency on the high end of the dial by the trimmer cap on the oscillator gang.
That gave me good tracking over the whole dial.
See my latest post in special builds.

Cheers, Fred.


 
 Return to top of page · Post #: 12 · Written at 10:14:10 PM on 11 May 2022.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4701

Making the slug and since then winning a box full of NOS. was interesting. Ferrite is like granite and is brittle; it actually had to be wrapped in paper in the lathe chuck & ground down with a die grinder. I deliberately made it over length to my guesstimation and ground the excess off with the bench grinder.

Fred fairly conventional tuning method with those things. Tuning gang & its coils are manufactured as a matched set and set up in the factory, such that they "track" one another. Putting in a foreign coil into that coils set, if there is a failure, can cause some serious "tracking" issues.

Marc


 
 Return to top of page · Post #: 13 · Written at 9:59:53 AM on 12 May 2022.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4701

Step one in dial calibration, is mechanical calibration. A broad statement involving any repairs to the drive such that the pointer is at the extremes of the dial when the gang rotor, or ferrite slugs etc. are at their extremes.

Failure to do that procedure could see the adjustments outside of their range. Some sets do have (hidden on Kriesler if its cased) a mark on the dial "set pointer here". Plus other set points.

Marc


 
 Return to top of page · Post #: 14 · Written at 2:35:08 PM on 16 May 2022.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1773

Well I did manage to transpose a coil from another Mickey into this KL. Two issues I overcame was the hole in the chassis was for a different shaped coil fitting which I drilled out to a perfect fit. And there were only three ways I could wire the coil in Smile and the first two were wrong Smile , once I had wired it in the correct way everything came to life and sensitivity was good plus the tracking seemed accurate.
It did have a inherent static noise once the volume was past a certain low level which I actually tracked to the speaker wires going to the cone. This problem I solved by placing a bit of soft insulation wool between the cone and it's frame and it now has good fidelity. I will pull the speaker down next weekend and do a proper job. The case needs repairing and needs knobs. I have obtained a good dial for it as well so this sows ear may look like a silk purse after all Smile .

I even tested my newly serviced leader 10 signal generator and it seems to be pretty spot on.


 
 Return to top of page · Post #: 15 · Written at 12:25:59 AM on 17 May 2022.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4701

Do beware with some of those Leader generators. They are not all made in the same factory. Some have oil filed caps & they are bad news.

Some, not only them have two wire cables and a metal case with a line cap of dubious integrity going to the metal case. How they got into the country I do not know. They depend on that cap being on Neutral. Naturally I do not like that idea, and relying on an RCD to protect me is not on the bucket list, & as they are normally transformer types: They get a grounded cable.


 
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