UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

David G4EBT · 12th Oct 2019, 11:20 am

You don't say where your interests lie, which obviously has a bearing on the type of components you'll need, and their working voltages.

For valve radios, the favoured replacement capacitors for tubular axial lead 'waxy' paper ones tend to be the yellow 630V polyester film ones. They're avaiable from a wide range of suupliers - Farnell, RS, Rapid Electronics, etc. Theyr'e often sold in lots of five, ten or more, so if you buy them as needed, you usually have them by return of post, and over time, you tend to build up stocks of the more commonly used valuers, without ending up with some that you'd never use.

I generally get mine from a UK supplier on eBay - 'Dunkselectroshop':

630V polyester axial lead capacitors, 5% tolerance in a range of values in packs of ten, typically £3.50 - £4.50 plus 99p post:

https://www.ebay.co.uk/str/dunkselec...p2047675.l2563

Cricklewood, sell them, typically £1.50 - £2.00 each plus £1.50 post.

https://www.ebay.co.uk/itm/Polyester...ujsVzpx1D6mSrQ

They're also available at BVWS events to anyone, or by mail to members only.

Some restorers seem to prefer radial leaded 'box' shaped Metallised Polyester Film Capacitor, which are a little more compact. They're usually ±10% tolerance and come in a range of voltages, 100V 250V 400V 630V. To cover most needs, the 630V ones are the best choice. Available from several UK suppliers. I get mine from an eBay shop, typically £1.49 for ten post free, so over time, a personal stock of the most commonly used values tends to build up:

https://www.ebay.co.uk/itm/Metallise....c100005.m1851

For low voltage use on homebrew projects or transistor radio repair/restoration, I usually use 'Mylar' polyester film capacitors with radial leads. You can get them in packs of several useful values. I bought one of these packs some time ago and still have lots left. The packs are so cheap that it hardly matters if there are some in the assortment that never get used: 700pcs of 24 Values, Mylar Polyester Film Capacitor Assortment Pack Kit DC 100V C4R7 £11.71 UK supplier:

https://www.ebay.co.uk/itm/700pcs-24....c100005.m1851

As well as capacitors, when restoring vintage valve radios, resistors are often well outside of tolerance, which originally tended to be either 10% or 20%. I generally replace any that are much over 20%. Valve radios commonly used half-Watt and a few 1Watt resistors, but modern half-Watt replacements are so tiny that they look out of place and not up to the task, even though they are. As replacements, as with other restorers, I use 2 Watt carbon film ones, which look more in keeping and cover most eventualities as there are few resistors in most radios above 2 Watts.

I know that some restorers prefer to steer clear of aBay and use only companies such as CPC/Farnell and RS, and are wary about buying components from China. It's a personal choice, (but where else do they suppose that components are manufactured, whoever sells them?). I recently bought a pack of 150 carbon film 2 Watt 5% tolerance resistors in 30 useful values from 1K Ohm to 2M Ohm 5% from a supplier in China. There may be some I never use, but at £5.09 & £1.00 p&p for a pack of 150, it doesn't really matter. They arrived in 25 days and on a sample that I've checked, they're well within the 5% tolerance, in fact mostly spot on:

https://www.ebay.co.uk/itm/1K-Ohm-to...72.m2749.l2649

Hope that's helpful.

12th Oct 2019, 11:20 am	#9
David G4EBT Dekatron Join Date: Feb 2003 Location: Cottingham, East Yorkshire, UK. Posts: 5,761	Re: Capacitors to stock? You don't say where your interests lie, which obviously has a bearing on the type of components you'll need, and their working voltages. For valve radios, the favoured replacement capacitors for tubular axial lead 'waxy' paper ones tend to be the yellow 630V polyester film ones. They're avaiable from a wide range of suupliers - Farnell, RS, Rapid Electronics, etc. Theyr'e often sold in lots of five, ten or more, so if you buy them as needed, you usually have them by return of post, and over time, you tend to build up stocks of the more commonly used valuers, without ending up with some that you'd never use. I generally get mine from a UK supplier on eBay - 'Dunkselectroshop': 630V polyester axial lead capacitors, 5% tolerance in a range of values in packs of ten, typically £3.50 - £4.50 plus 99p post: https://www.ebay.co.uk/str/dunkselec...p2047675.l2563 Cricklewood, sell them, typically £1.50 - £2.00 each plus £1.50 post. https://www.ebay.co.uk/itm/Polyester...ujsVzpx1D6mSrQ They're also available at BVWS events to anyone, or by mail to members only. Some restorers seem to prefer radial leaded 'box' shaped Metallised Polyester Film Capacitor, which are a little more compact. They're usually ±10% tolerance and come in a range of voltages, 100V 250V 400V 630V. To cover most needs, the 630V ones are the best choice. Available from several UK suppliers. I get mine from an eBay shop, typically £1.49 for ten post free, so over time, a personal stock of the most commonly used values tends to build up: https://www.ebay.co.uk/itm/Metallise....c100005.m1851 For low voltage use on homebrew projects or transistor radio repair/restoration, I usually use 'Mylar' polyester film capacitors with radial leads. You can get them in packs of several useful values. I bought one of these packs some time ago and still have lots left. The packs are so cheap that it hardly matters if there are some in the assortment that never get used: 700pcs of 24 Values, Mylar Polyester Film Capacitor Assortment Pack Kit DC 100V C4R7 £11.71 UK supplier: https://www.ebay.co.uk/itm/700pcs-24....c100005.m1851 As well as capacitors, when restoring vintage valve radios, resistors are often well outside of tolerance, which originally tended to be either 10% or 20%. I generally replace any that are much over 20%. Valve radios commonly used half-Watt and a few 1Watt resistors, but modern half-Watt replacements are so tiny that they look out of place and not up to the task, even though they are. As replacements, as with other restorers, I use 2 Watt carbon film ones, which look more in keeping and cover most eventualities as there are few resistors in most radios above 2 Watts. I know that some restorers prefer to steer clear of aBay and use only companies such as CPC/Farnell and RS, and are wary about buying components from China. It's a personal choice, (but where else do they suppose that components are manufactured, whoever sells them?). I recently bought a pack of 150 carbon film 2 Watt 5% tolerance resistors in 30 useful values from 1K Ohm to 2M Ohm 5% from a supplier in China. There may be some I never use, but at £5.09 & £1.00 p&p for a pack of 150, it doesn't really matter. They arrived in 25 days and on a sample that I've checked, they're well within the 5% tolerance, in fact mostly spot on: https://www.ebay.co.uk/itm/1K-Ohm-to...72.m2749.l2649 Hope that's helpful. __________________ David. BVWS Member. G-QRP Club member 1339.