Old radio, quite rare

[MBfreak]

I have been restoring a SOUNDRADIO from 1951. Swedish made, company dead since 1960. No schematic available and unusual design.
Also cheap components, all 7 tubes were shot, but easy to find.
The radio is AM only. MW and LW with 5 short wave bands. +- 500 kHz bandspread SW tuning.
The input IF converter/ local osc tube is a 12AT7 double triode, which I had only read about, never seen. Obviously the entire design is stolen from US economy design radios.
The 12AT7 tube socket sits very cramped and had contat difficulties. Had to be pushed over for the osc to run. Tried to polish/clean socket and tube pins but still bad. The tube pins are 1,0 mm and socket is a fork in iffy metal.
Not wanting to replace socket I applied my considerable and most often fatal modifying skills.
Alu household sheet folded thrice ( 3x 0,04 mm) and cut down to 1,3 mm W and 12 mm L strip. I knew it was the oscillator on pins 6, 7 and 8 that was iffy. Pushed down the alu strips with a 0,8 mm screwdriver and forced back the 12AT7.
PERFECT.

True shade tree radio repair shop!

Ola

 

[Eli D]

I have a few old radios I want to repair myself. Do you have any good sources for info on troubleshooting?

 

[malibu101]

In no way shape or form affiliated with him--

But I am amazed by the skill of Mr. Carlsons Lab on Youtube.
This reminds me of that.

 

[willy3486]

I have a few old radios I want to repair myself. Do you have any good sources for info on troubleshooting?

If you are on facebook there are a few good groups there I am a member of. Usually if you get stumped and post the issue someone will chime in with a solution to try in a few minutes. A good source out there for info is the World radio history site. This is one of the best sites I have found for info. Just look around and you can find all kinds of stuff from repair info to sales brochures.

SALES and SERVICE COLLECTION: Unique or short-run publications.

This is a collection of single editions, booklets or periodicals for which we have only a few editions. They cover radio and television sales and service.

worldradiohistory.com

Another good site to look for individual radios is

Antique Radios, 335 040 Antique Radios listed

Radio Museum, ANTIQUE RADIOS: 335 040 Antique Radios, Schematics, Pictures - Radio Catalog

www.radiomuseum.org

As far as learning how to work on them the best way is just to tinker and teach yourself. Its a great hobby and not as costly as autos.

Good job on getting it going. The European radios are odd to me as I haven't worked on many. I like how many here in the US are made. As far as radios go I hate it when a socket gets so corroded its not making good contact. I usually spray a good contact cleaner then wiggle the tube a lot. Many times it cleans it but if not the socket comes out to be replaced. I have been tinkering with them since about 1978. I have fixed thousands of them and probably still have close to a thousand of them myself, I am not sure of the exact number.

 

[Blueshound_GJ]

I have been restoring a SOUNDRADIO from 1951. Swedish made, company dead since 1960. No schematic available and unusual design.
Also cheap components, all 7 tubes were shot, but easy to find.
The radio is AM only. MW and LW with 5 short wave bands. +- 500 kHz bandspread SW tuning.
The input IF converter/ local osc tube is a 12AT7 double triode, which I had only read about, never seen. Obviously the entire design is stolen from US economy design radios.
The 12AT7 tube socket sits very cramped and had contat difficulties. Had to be pushed over for the osc to run. Tried to polish/clean socket and tube pins but still bad. The tube pins are 1,0 mm and socket is a fork in iffy metal.
Not wanting to replace socket I applied my considerable and most often fatal modifying skills.
Alu household sheet folded thrice ( 3x 0,04 mm) and cut down to 1,3 mm W and 12 mm L strip. I knew it was the oscillator on pins 6, 7 and 8 that was iffy. Pushed down the alu strips with a 0,8 mm screwdriver and forced back the 12AT7.
PERFECT.

True shade tree radio repair shop!

Ola

Zen and the Art of Radio Maintenance. Nice work on the shim

 

[MBfreak]

Blueshound
My tweaks usually are useless and sets me back. But the household alu was a winner. One of my few.
And I am a very very long way from Mr Pirsig. One of our great individuals up there with Richard Feynman, Robert Johnson, Muddy Waters and Marcia Ball.
Duke Ellington surpasses them all together with Johnny Hodges , Barney Bigard and Fess.
Love them all

Ola

 

[littleboss]

I restored a few but got bored. Replacing every capacitor and rubber wires is boring and takes no skill. I moved on to more challenging things..

 

[willy3486]

I restored a few but got bored. Replacing every capacitor and rubber wires is boring and takes no skill. I moved on to more challenging things..

LOL, find one "repaired " by someone that was a "expert" who didn't get it going if you want a challenge. I have done a few like that. As far as boring I like that it is "boring" After a few days of stressful work its nice to redo something that is not draining mentally. As far as no skill to do if you run into one you have to troubleshoot where the problem is you have to have knowledge and skill. Caps and rotted wiring is the issue with most of them but not all. Some of the best deals on radios I have got are ones others could not figure out.

 

[littleboss]

LOL, find one "repaired " by someone that was a "expert" who didn't get it going if you want a challenge. I have done a few like that. As far as boring I like that it is "boring" After a few days of stressful work its nice to redo something that is not draining mentally. As far as no skill to do if you run into one you have to troubleshoot where the problem is you have to have knowledge and skill. Caps and rotted wiring is the issue with most of them but not all. Some of the best deals on radios I have got are ones others could not figure out.

The only one that was interesting to me was an old 5 bander where the osc coil was corroded and shorted out. I had to rewind all 5 coils.

 

[Davefr]

LOL, find one "repaired " by someone that was a "expert" who didn't get it going if you want a challenge.

Especially one where someone thought that the problem was simply RF tuner alignment and proceeded to adjust a perfectly aligned tuner in a broken radio. Now you have bad alignment and a broken radio to try and sort out. Even worse if it's FM stereo.

 

[inphx]

For diagnosis on tubes, usually in my experience a bad tube has a burned out filament. and the filaments are often ran in series so none of the rubes get hot.. so i just ohm out and locate the burned out tube and usually that's the quick fix. then you have a buzzing sound and that's the dried capacitors to replace. Other issues are mechanical - the thread or pulleys for the tuner, cracked knobs etc...

 

[MBfreak]

WRT getting bored, that happens to people who screw easy things up.
And brag about it. Like our beloved handle littleboss.

Ifyou want to see the work of an absolutely top notch radio restorer, go thru the posts from Radio Ron. He used to be quite active here on GJ, but not lately.
One of his more salient remarks was " and replacing a broken scale wire is usually the hardest part.

Ola