Worth checking if valve really needs replacing. Have come across so many where rattle is only due to loose cement in base. Electolytic capacitors in smoothing circuit are likely troublemakers.
I'll have a look, when I opened this radio up to remove the packing styrofoam it had been stuffed with it appeared all the capacitors had been replaced. I'll see if any have prematurely failed.
@@toomanyinterests Have heard of exploding electrolytics & even come across early liquid filled ones with vents. Sounds frightening. Many collectors power up old sets gradually using a variac. Some say this gradual approach allows long unused electrolytics to 'form up' rather than failing catasrophically. Not sure of the life of an electrolytic, but in the 1960's have seen early 1930's sets work perfectly with original components.
@@tiga4180Liquid-filled electrolytics are described in the book "Radio Physics Course" I have, a comprehensive textbook from 1933. It also states electrolytics are "self-healing", they can rebuild the dielectric layer after breakdown from over-voltage. Applying voltage for a long period of time is how the dielectric in capacitors is formed in production, but the applied voltage is over the intended working voltage. If the water and glycerine of the electrolyte has evaporated over time, I don't think any method of voltage application will improve the capacitor. I do power up any older electronics using a variac so if there are any serious issues I can spot them while causing the least possible damage. Years ago I had one radio where an electrolytic had a bulge, on plugging it in it caused a valve to arc, but only once. To my surprise after replacing the problematic capacitor, the valve was still fine and the radio now works.
Worth checking if valve really needs replacing. Have come across so many where rattle is only due to loose cement in base. Electolytic capacitors in smoothing circuit are likely troublemakers.
I'll have a look, when I opened this radio up to remove the packing styrofoam it had been stuffed with it appeared all the capacitors had been replaced. I'll see if any have prematurely failed.
@@toomanyinterests Have heard of exploding electrolytics & even come across early liquid filled ones with vents. Sounds frightening. Many collectors power up old sets gradually using a variac. Some say this gradual approach allows long unused electrolytics to 'form up' rather than failing catasrophically. Not sure of the life of an electrolytic, but in the 1960's have seen early 1930's sets work perfectly with original components.
@@tiga4180Liquid-filled electrolytics are described in the book "Radio Physics Course" I have, a comprehensive textbook from 1933. It also states electrolytics are "self-healing", they can rebuild the dielectric layer after breakdown from over-voltage. Applying voltage for a long period of time is how the dielectric in capacitors is formed in production, but the applied voltage is over the intended working voltage. If the water and glycerine of the electrolyte has evaporated over time, I don't think any method of voltage application will improve the capacitor.
I do power up any older electronics using a variac so if there are any serious issues I can spot them while causing the least possible damage.
Years ago I had one radio where an electrolytic had a bulge, on plugging it in it caused a valve to arc, but only once. To my surprise after replacing the problematic capacitor, the valve was still fine and the radio now works.
Har har 🗣️🗣️🔥🔥🔥🔥 i am no one hehe