Battery eliminator power supply - UK Vintage Radio Repair and Restoration Discussion Forum

antcus · 12th Sep 2011, 11:12 pm

I am in the process of building the power supply described on this site, but am getting confused about the polarity of the capacitors as shown in the pictorial. The capacitors have a band at one end, but they seem to be connected to the positive side even though the band usually indicated the negative side of a capacitor? Where am I getting confused?
I have been building and repairing radios since I was 9 years old, and cannot figure out what is confusing me in such a simple circuit.

Alistair D · 12th Sep 2011, 11:21 pm

Please post a picture of the caps. mny Philips axial caps of the 70s had a black band close to the +ve terminal.

Al

antcus · 13th Sep 2011, 8:50 pm

It is not a picture, just go to the "Things to make" section of this site and you will see a drawing with these lines showing. Just let me know if you have made out where my difficulty lies.

Yes i can imagine how you discovered the capacitor polarity....you were playing with popping fireworks were'nt you??

Amraduk · 13th Sep 2011, 9:14 pm

Quote:

Originally Posted by antcus

It is not a picture, just go to the "Things to make" section of this site and you will see a drawing with these lines showing. Just let me know if you have made out where my difficulty lies.

Are you referring to the drawing in the attachment? If so, the bands indicate the positive terminal of the capacitors (and shouldn't be confused with the band on the actual capacitors which is close the the negative terminal), it's an unusual way of showing the polarity but I guess that's just the way the author does it!

Regards,

Dave.

antcus · 14th Sep 2011, 7:50 pm

Thank heaven for that. I got so confused, and I knew it was all about nothing. I would say VERY UNUSUAL that the author has used this designation to indicate the positive. Now I can build it with peace of mind

Thanks a lot David. You did a great job to reassure my ageing mind!!! LOL

Amraduk · 14th Sep 2011, 8:12 pm

Quote:

Originally Posted by antcus

Thanks a lot David. You did a great job to reassure my ageing mind!!! LOL

You're welcome. Glad to be of some help!

Regards,

Dave.

Herald1360 · 19th Sep 2011, 7:44 pm

Didn't Philips blue axial electrolytics have a crimp indent just inboard of the sealing disc at the positive end which would look rather like the capacitors depicted in the sketch referenced? Complete with black line at the negative end too!

12th Sep 2011, 11:12 pm	#1
antcus Retired Dormant Member Join Date: Nov 2006 Location: Mosta, Malta Posts: 4	Battery eliminator power supply I am in the process of building the power supply described on this site, but am getting confused about the polarity of the capacitors as shown in the pictorial. The capacitors have a band at one end, but they seem to be connected to the positive side even though the band usually indicated the negative side of a capacitor? Where am I getting confused? I have been building and repairing radios since I was 9 years old, and cannot figure out what is confusing me in such a simple circuit.

12th Sep 2011, 11:21 pm	#2
Alistair D Nonode Join Date: Jan 2010 Location: Edinburgh, UK. Posts: 2,008	Re: Battery eliminator power supply Please post a picture of the caps. mny Philips axial caps of the 70s had a black band close to the +ve terminal. Al __________________ I won't tell you how I discovered that.

13th Sep 2011, 8:50 pm	#3
antcus Retired Dormant Member Join Date: Nov 2006 Location: Mosta, Malta Posts: 4	Re: Battery eliminator power supply It is not a picture, just go to the "Things to make" section of this site and you will see a drawing with these lines showing. Just let me know if you have made out where my difficulty lies. Yes i can imagine how you discovered the capacitor polarity....you were playing with popping fireworks were'nt you??

14th Sep 2011, 7:50 pm	#5
antcus Retired Dormant Member Join Date: Nov 2006 Location: Mosta, Malta Posts: 4	Re: Battery eliminator power supply Thank heaven for that. I got so confused, and I knew it was all about nothing. I would say VERY UNUSUAL that the author has used this designation to indicate the positive. Now I can build it with peace of mind Thanks a lot David. You did a great job to reassure my ageing mind!!! LOL

19th Sep 2011, 7:44 pm	#7
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: Battery eliminator power supply Didn't Philips blue axial electrolytics have a crimp indent just inboard of the sealing disc at the positive end which would look rather like the capacitors depicted in the sketch referenced? Complete with black line at the negative end too! Attached Thumbnails __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O