Electronic restoration.
As stated in my first post on this Saba Wildbad 100 restoration, the paper capacitors had to go. However I gave it a quick cursory power up using my Lamp Limiter (A 40 watt lamp in series with the power cable to absorb any nasty surprises in the radio) and it is confirmed: the radio lit up and talked to me on FM with a distorted voice. The Shortwave selection also worked but medium and long wave were silent.
Even the magic eye lit up. Not a bad start, so time to change some capacitors..
A few screws and de-soldering the speakers reveals the chassis and a good number of paper capacitors. Two were of particular interest to me: the ones isolating the output stage of the detector going to the preamp tube (ECH81), and the other from the preamp to the power amp (EL84).
The big paper bombs waiting to explode the radio.
Their days were numbered.
Following a cleaning and repairing the dial cord for the directional antenna, I discovered that there was no reception on MW and LW. It took some tracing to discover that the rotary ferrite antenna coil was open circuit.
Some soldering solved the problem. It's a delicate process because the wire on the ferrite core is extremely fragile. This kind of problem is a lot easier to spot when everything is clean.
Some soldering solved the problem. It's a delicate process because the wire on the ferrite core is extremely fragile. This kind of problem is a lot easier to spot when everything is clean.
I was ready to put the chassis into the cabinet for a test.
Cleaning involved a spray bottle with liquid laundry soap in a strong dilution with water and squirting the entire chassis, top and bottom and working with a 1" paint brush. I then flushed out with hot water and set it out on the radiator in the living room to dry overnight. It works perfectly, but patience is the key. If you power it up while the transformers are still wet inside, it's going to fry on you!!
Getting the Wildbad 100 back into the chassis is always a milestone for me. It's satisfying to see it all spruced up and ready to play. I also fitted a Bluetooth receiver module in the bottom of the cabinet. It brings the radio into the 21's century but keeps it looking original.
Back in the cabinet and singing like a bird. the 24 hour test was passed with no issues.
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