12-26-2012, 10:05 PM
Today I stopped by the electronics store and bought the six caps needed to replace the paper jobbies in the set plus three electrolytics needed. The schematic called for 30 and a 25 and 20uf caps at 150v. I couldn't find those so I got a 47uf at 160v and two 30uf at the same voltage...ready to go for tonight.
Right after supper, my dog waited patiently in the computer room while I was out in the garage(attached to house) working on the radio. I replaced quite a few of the caps and then started replacing the ones in the can. I took it out, added a terminal block and tied all negative leads(I thought) to the terminal block and the the positive leads to their respective places. Once I got all that done I powered it up and got the loudest hum I had ever heard. I unplugged it and rechecked my wiring for shorts and all was fine there. I found even though I had tied the negatives to the terminal block, I failed to take another wire from there to B-. Turned it on again and after a few seconds the dial light got real bright and then went out and nothing came out of the radio. I unplugged it, looked over things again and discovered two of the electrolytics were indeed tied to each others negative but the larger 47uf cap had it's positive tied to what I thought was the negative of the other two!!.
I now have a dead radio, no sound at all. I checked the electrolytics and all three read around 112uf. I decided nothing to loose so turned it on and measured the voltage across them and zero. so was the voltage across the rectifier.
This is what happens when you're in a hurry and not paying enough attention to what you're doing and I was feeling guilty about neglecting my buddy in the next room and rushed too much. Have I just blown the electrolytics or those and all the tubes as well? Lessons learned the hard way-DON'T GET IN A HURRY!
Right after supper, my dog waited patiently in the computer room while I was out in the garage(attached to house) working on the radio. I replaced quite a few of the caps and then started replacing the ones in the can. I took it out, added a terminal block and tied all negative leads(I thought) to the terminal block and the the positive leads to their respective places. Once I got all that done I powered it up and got the loudest hum I had ever heard. I unplugged it and rechecked my wiring for shorts and all was fine there. I found even though I had tied the negatives to the terminal block, I failed to take another wire from there to B-. Turned it on again and after a few seconds the dial light got real bright and then went out and nothing came out of the radio. I unplugged it, looked over things again and discovered two of the electrolytics were indeed tied to each others negative but the larger 47uf cap had it's positive tied to what I thought was the negative of the other two!!.
I now have a dead radio, no sound at all. I checked the electrolytics and all three read around 112uf. I decided nothing to loose so turned it on and measured the voltage across them and zero. so was the voltage across the rectifier.
This is what happens when you're in a hurry and not paying enough attention to what you're doing and I was feeling guilty about neglecting my buddy in the next room and rushed too much. Have I just blown the electrolytics or those and all the tubes as well? Lessons learned the hard way-DON'T GET IN A HURRY!
