Author Topic: What a mess  (Read 313 times)

Offline eskoilola

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What a mess
« on: October 03, 2017, 04:15:39 AM »
Ever started to repair something that at first glance seems to be like an easy task but turned out to be a trip in the park ... with 100 monkeys.
After all these well over 300 more or less restored electronic home appliances I have had my share of that.
Here are some highligths - I wish I would have pictures of all the surprises along the way...

This "HiFi" reel-to-reel tape recorder was clean, it did not have too many dried capacitors or other common electronic trouble. The only problem was that it did not run mechanically. A broken belt somewhere?


After taking apart a few parts on the top to get access to the belt drive system I had a real surprise waiting...
Each and every "rubber" part had gone through a metamorphosis into some slimy and VERY sticky stuff. This appliance has a LOT of these. At first sight the parts seemed to be allright but when I touched them, they stick into my finger like glue....


I found some of the parts in my stock but some parts were a tad special so I had to make them. So how do You turn rubber?
The "dust" around is not dust. It is frost and some dust. Figured out that turning rubber can be done by freezing it down with cold-spray and then turning it with really sharp tool.


After some really painful cleaning I finally got all the goo out and the unit run just fine. The funky knob was later replaced with a less funky variant.


I for sure have had my share of Philips appliances. I really have to say that after these Years I will never get myself a device that has a name "Philips" written on it. They can be bad. Some were beyond repair. Some took a lot of work to get back in decent condition but none of them was really good.

This was a nice looking radio that was not supposed to be a big deal to repair. Well..... I decided not to.
However, I cannibalized the electrolytic capacitor (leftmost cylinder) as I had another similar radio that was in need of this component. It turned out that this capacitor was bad as well.
One way to restore that kind of electrlytic capacitor is to open it and then replace the contents with modern component. Works great and looks original.
The easiest way to open these is to put them in lathe and turn them open at the bottom.
What I did not know was that this particular capacitor was not filled with the usual paper+aluminium stuff. This one had real liquid inside... Simple capacitor repair turned into lathe cleanup.


Another radio. Philips Matador from 30's this time. Decided to cut off the mains cord and screw the back cover back. Some bakelite polishing and give to a friend to be placed on top of fireplace.


This TV is from the early 50's. It was a real pain to fix as it had nothing but bad quality components inside. I wish I had documented all the parts I had to replace to get this one working.
These are also outright dangerous to repair. The acceleration voltage for the CRT (Picture tube) is around 20 kilovolts. The back of the CRT has a graphite coating making it a large capacitor. That capacitor can retain the charge for months. So even when the unit is not powered it can kill You.
Another danger with these older sets is the CRT implosion.


Online awemawson

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Re: What a mess
« Reply #1 on: October 03, 2017, 05:39:35 AM »
That 'graphite coating' we called Aquadag back in the day
Andrew Mawson
East Sussex

Offline seadog

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Re: What a mess
« Reply #2 on: October 03, 2017, 06:48:19 AM »
Belts turning to goo is not uncommon. I've refurbished a couple of Eumig projectors in the last couple of years and the belts on those turn to a horrible black, sticky mess, too.

It's satifying repairing old equipment.