Loewe Opta Magnet 3737 - UK Vintage Radio Repair and Restoration Discussion Forum

Joe_Lorenz · 25th Nov 2023, 11:23 pm

Recently I got that 1959 radio on the bench from a friend telling me it had been sitting dead in his late father's living room for decades and he would rather see it working once again now. So, having a closer look I found the cabinet in a very decent state, clean control knobs, not much used all in all. Removing the chassis allowed to see a cooked 1200 Ohms 2 Watt resistor, directly between both smoothing caps after the anode voltage rectifier. Putting a new one in was the first idea: Firing it up carefully on the variac produced that resistor getting hot at 100 V. Now I took a close look at the schematics: That resistor had been soldered to a wrong lug, thus making a short! Correcting that error did the job, well, almost. A hand full of bad old WIMA caps waited to be changed in favour of new ones, and voila, we had good FM reception and a full sound.

So it will be soon back to the owner, ready for some more decades!

Regards, Joe

P.S.: Sorry for the poor quality of the photos. Burning the midnight oil ...
The schematics are published on NVHR.nl if someones needs them

Red to black · 26th Nov 2023, 12:10 am

Good stuff by Lowe opta

25th Nov 2023, 11:23 pm	#1
Joe_Lorenz Heptode Join Date: Dec 2019 Location: Hohenroda, Eastern Hesse, Germany Posts: 504	Loewe Opta Magnet 3737 Recently I got that 1959 radio on the bench from a friend telling me it had been sitting dead in his late father's living room for decades and he would rather see it working once again now. So, having a closer look I found the cabinet in a very decent state, clean control knobs, not much used all in all. Removing the chassis allowed to see a cooked 1200 Ohms 2 Watt resistor, directly between both smoothing caps after the anode voltage rectifier. Putting a new one in was the first idea: Firing it up carefully on the variac produced that resistor getting hot at 100 V. Now I took a close look at the schematics: That resistor had been soldered to a wrong lug, thus making a short! Correcting that error did the job, well, almost. A hand full of bad old WIMA caps waited to be changed in favour of new ones, and voila, we had good FM reception and a full sound. So it will be soon back to the owner, ready for some more decades! Regards, Joe P.S.: Sorry for the poor quality of the photos. Burning the midnight oil ... The schematics are published on NVHR.nl if someones needs them Attached Thumbnails

26th Nov 2023, 12:10 am	#2
Red to black Nonode Join Date: Mar 2010 Location: Sunderland, Tyne and Wear, UK. Posts: 2,518	Re: Loewe Opta Magnet 3737 Good stuff by Lowe opta __________________ I don't suffer from Insanity. I enjoy every minute of it.