R1155 caps - UK Vintage Radio Repair and Restoration Discussion Forum

CesarLG · 18th Dec 2018, 9:21 am

Hello! I would like to replace the electrolytic caps as I always donon my old radios... but I see that R1155 doesn’t have any. Is that correct?

HamishBoxer · 18th Dec 2018, 9:30 am

Yes I believe you are correct apart from main smoothing electrolytic s in a separate power supply,there are possibly one or two smaller biasing caps.
Note this is without looking.

CesarLG · 18th Dec 2018, 9:58 am

Thanks! What about the voltage rating on the picofarad ones?

M0FYA Andy · 18th Dec 2018, 10:09 am

No electrolytics in an R1155.
There are in the monster Air Ministry ground power supply, but that's another matter.

Andy

AC/HL · 18th Dec 2018, 2:56 pm

Quote:

Originally Posted by CesarLG

Thanks! What about the voltage rating on the picofarad ones?

Unless there is a definite fault, it's not advisable to touch capacitors with low picofarad values. They're unlikely to be faulty, and are likely to disturb alignment.

cmjones01 · 18th Dec 2018, 4:28 pm

My R1155 has (had) lots of metal-cased paper capacitors (branded TCC, I think) which look a bit like electrolytics. The ones in mine are hopelessly leaky, to the point of making fizzing bubbling noises due to electrolysis when HT was applied. They certainly needed replacing (I chose to restuff some because of their chassis mounting method) but they weren't electrolytic.

Chris

CesarLG · 19th Dec 2018, 8:46 am

I have no problems with them I experience good reception and sound. But I think that the CW BFO setting is not performing at 100%... May it be due to that caps?
Where did you find that 2.5uf? I have just odered them but they are not easy to get

HamishBoxer · 19th Dec 2018, 9:43 am

A 2.2uF is a perfect replacement for 2.5uF

Keith · 20th Dec 2018, 3:33 pm

As Chris says, the double and triple tubular decoupling capacitors are usually leaky and will degrade the performance of the receiver. I ended up restuffing mine with modern polypropylenes which should solve the problem long term.

18th Dec 2018, 9:21 am	#1
CesarLG Tetrode Join Date: Apr 2018 Location: Barcelona, Spain. Posts: 62	R1155 caps Hello! I would like to replace the electrolytic caps as I always donon my old radios... but I see that R1155 doesn’t have any. Is that correct? __________________ EA3IAV Last edited by CesarLG; 18th Dec 2018 at 9:40 am.

18th Dec 2018, 9:30 am	#2
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,931	Re: R1155 caps Yes I believe you are correct apart from main smoothing electrolytic s in a separate power supply,there are possibly one or two smaller biasing caps. Note this is without looking. __________________ G8JET BVWS Archivist and Member V.M.A.R.S

18th Dec 2018, 9:58 am	#3
CesarLG Tetrode Join Date: Apr 2018 Location: Barcelona, Spain. Posts: 62	Re: R1155 caps Thanks! What about the voltage rating on the picofarad ones? __________________ EA3IAV

18th Dec 2018, 10:09 am	#4
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,511	Re: R1155 caps No electrolytics in an R1155. There are in the monster Air Ministry ground power supply, but that's another matter. Andy

18th Dec 2018, 4:28 pm	#6
cmjones01 Nonode Join Date: Oct 2008 Location: Warsaw, Poland and Cambridge, UK Posts: 2,676	Re: R1155 caps My R1155 has (had) lots of metal-cased paper capacitors (branded TCC, I think) which look a bit like electrolytics. The ones in mine are hopelessly leaky, to the point of making fizzing bubbling noises due to electrolysis when HT was applied. They certainly needed replacing (I chose to restuff some because of their chassis mounting method) but they weren't electrolytic. Chris __________________ What's going on in the workshop? http://martin-jones.com/

19th Dec 2018, 8:46 am	#7
CesarLG Tetrode Join Date: Apr 2018 Location: Barcelona, Spain. Posts: 62	Re: R1155 caps I have no problems with them I experience good reception and sound. But I think that the CW BFO setting is not performing at 100%... May it be due to that caps? Where did you find that 2.5uf? I have just odered them but they are not easy to get __________________ EA3IAV

19th Dec 2018, 9:43 am	#8
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,931	Re: R1155 caps A 2.2uF is a perfect replacement for 2.5uF __________________ G8JET BVWS Archivist and Member V.M.A.R.S

20th Dec 2018, 3:33 pm	#9
Keith Heptode Join Date: Jan 2003 Location: Tewkesbury, Gloucestershire, UK. Posts: 693	Re: R1155 caps As Chris says, the double and triple tubular decoupling capacitors are usually leaky and will degrade the performance of the receiver. I ended up restuffing mine with modern polypropylenes which should solve the problem long term. Attached Thumbnails __________________ Keith Yates - G3XGW VMARS & BVWS member http://www.tibblestone.com/oldradios/Old_Radios.htm