90v battery - UK Vintage Radio Repair and Restoration Discussion Forum

Andy40uk · 25th Apr 2008, 6:51 pm

Where do I get one of these or is it impossible nowadays?

Andy

Steve_P · 25th Apr 2008, 7:10 pm

You can get one made up that will take PP3's. The HT on a radio that takes this voltage is at very low current. I just get 10 x PP3 and strap them together. Cheap ones will do.

Cheers,

Steve P.

paulsherwin · 25th Apr 2008, 7:10 pm

Quote:

Originally Posted by Andy40uk

Where do I get one of these or is it impossible nowadays?

The short answer is yes, it is impossible nowadays.

The long answer is that there are a number of solutions available. The simplest is to make up a battery using 10 PP3 batteries from somewhere like Poundland as Steve suggests. A forum member, batterymaker1, runs a small business making high quality reproduction 90V batteries which take lots of PP3s. Alternatively you can build a mains power supply to produce the 90V. It's also possible to build or buy an inverter that will produce 90V from 6V or 9V. It all depends on what you want to do.

Paul

Sideband · 25th Apr 2008, 9:54 pm

An example of Bills (Batterymaker) work is shown here https://www.vintage-radio.net/forum/...ad.php?t=25037

I used one of his repro batteries to give my P4D the finishing touch. The battery opens up to reveal 10xPP3 for 90v and a couple of 'C' cells for the LT.

Rich.

Andy40uk · 26th Apr 2008, 12:06 pm

Thanks for the info. If I get 10 pp3's and strap them together how do I connect them up

(I'm totally new to this and know nothing at the moment). The battery is for a Roberts R66.

Andy

russell_w_b · 26th Apr 2008, 2:01 pm

Quote:

Originally Posted by Andy40uk

Thanks for the info. If I get 10 pp3's and strap them together how do I connect them up

(I'm totally new to this and know nothing at the moment). The battery is for a Roberts R66.

Andy

You might find the attached pics of interest, taken from the 'Newnes' 1956Radio & TV Engineers' Reference Book' - A trade advert, and some HT battery data.

Station X · 26th Apr 2008, 2:08 pm

You can obtain the Service Sheet for this radio by clicking on the link at the top right of this page.

There is only one way of connecting ten PP3s together. When you've done that you'll be left with one postive and one negative terminal exposed. connect these to the HT (High Tension) positive and HT negative terminals of the radio.

You'll also need a low tension (LT) battery to power the valve heaters.

Whatever you do don't connect the HT battery to the LT terminals. This will destroy one or more valves.

Alf · 26th Apr 2008, 4:54 pm

Hope this helps, it's just a matter of connecting the -ve of one battery to the +ve of another.

geofy · 26th Apr 2008, 5:20 pm

Quote:

Originally Posted by Andy40uk

Thanks for the info. If I get 10 pp3's and strap them together how do I connect them up

(I'm totally new to this and know nothing at the moment). The battery is for a Roberts R66.

Andy

As you are new to this, it is worth pointing out that 90Volts from batteries can pack a bit of a punch so be careful when connecting the terminals.

You could try alkaline PP3's as these will last longer, bulk buying will reduce the price and the radio will work down to about 60Volts HT so you could get away with less than ten batteries just to get it going. If you strap them pos to neg (this is the only way the clips will go) they can be held together with insulating tape or masking tape.

Geof

Herald1360 · 26th Apr 2008, 10:42 pm

A picture of the easiest way to connect up the batteries....

Dave Moll · 26th Apr 2008, 11:33 pm

... and the easiest way to obtain connectors for the two ends is to remove the terminal end from a dead PP3 battery, cut it in half and solder wires to the backs of the contacts. Creating a connector to fit the radio's original lead is a different matter, but you wouldn't want to spoil the radio by removing the original connector, would you?

russell_w_b · 27th Apr 2008, 12:01 am

Quote:

Originally Posted by Dave Moll

...but you wouldn't want to spoil the radio by removing the original connector, would you?

Just use a 'one-er' from a 5A barrier strip (choc-block connector) for each pin of the battery plug, and connect the wires to them from the salvaged press-stud battery terminal. Radio works, and no damage done to the battery plug; voila!

Station X · 27th Apr 2008, 10:49 am

Poundland in Carr Street Ipswich do cheap PP3s. I use them in my own 90V batteries.

Andy40uk · 27th Apr 2008, 11:19 am

Quote:

Originally Posted by Station X

Poundland in Carr Street Ipswich do cheap PP3s. I use them in my own 90V batteries.

I went there yesterday afternoon and got some, at 3 for a pound can't complain!

sentinel040 · 27th Apr 2008, 8:13 pm

Another way out is to look at the website for the Kit Radio Co (KRC), they do a rather good eliminator powered by AAA cells.

Pete_kaye · 30th Apr 2008, 4:17 pm

Is it possible to create 90V from a one or two 12 v car batteries?Also,is it simple to create 6,7.5 and 1.5v for heater use?

Herald1360 · 30th Apr 2008, 9:48 pm

It's certainly possible.... you would need to build a low power inverter to step up the 12V dc to around 75V ac, then rectify, filter and possibly regulate it to give 90V dc or maybe a little less.

The heater (filament) supplies are simpler- given the low currents simple linear regulators using LM317 or similar can be used to provide the supplies- maybe use 1.4, 5.6 and 7 volts since the filaments are rated at 1.4V which is about what you actually get from a partially discharged 1.5V dry cell.

Chris

squinancy · 30th Apr 2008, 10:41 pm

Hello. This is how I connected the ten 9V batteries for use in my portable Vidor, (which also needs a 1.5V battery). This way it fits into the original Ever Ready paper box that housed these batteries at one time before they were packed in metal. Here the wires are tightened around the contacts, but I have also produced soldered versions.

kalee20 · 1st May 2008, 11:07 am

For the quickest way of getting up and running, ten PP3 batteries in series for the HT will be the best way by far. Not the cheapest long-term - but certainly the most painless.

For the LT, again, use batteries (alkaline cells are best here). Herald1360 is dead right about linear regulators being a solution from a higher voltage, but types like the LM317 do produce rather a lot of noise, and the filament supply is very sensitive to this! You'll need a fair bit of filtering to make it clean - I've tried LM317's and heard nothing but mush!

25th Apr 2008, 6:51 pm	#1
Andy40uk Retired Dormant Member Join Date: Apr 2008 Location: Botswana Posts: 10	90v battery Where do I get one of these or is it impossible nowadays? Andy

25th Apr 2008, 7:10 pm	#2
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: 90v battery You can get one made up that will take PP3's. The HT on a radio that takes this voltage is at very low current. I just get 10 x PP3 and strap them together. Cheap ones will do. Cheers, Steve P. __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

25th Apr 2008, 9:54 pm	#4
Sideband Dekatron Join Date: Oct 2003 Location: Croydon, Surrey, UK. Posts: 7,571	Re: 90v battery An example of Bills (Batterymaker) work is shown here https://www.vintage-radio.net/forum/...ad.php?t=25037 I used one of his repro batteries to give my P4D the finishing touch. The battery opens up to reveal 10xPP3 for 90v and a couple of 'C' cells for the LT. Rich. __________________ There are lots of brilliant keyboard players and then there is Rick Wakeman.....

26th Apr 2008, 12:06 pm	#5
Andy40uk Retired Dormant Member Join Date: Apr 2008 Location: Botswana Posts: 10	Re: 90v battery Thanks for the info. If I get 10 pp3's and strap them together how do I connect them up (I'm totally new to this and know nothing at the moment). The battery is for a Roberts R66. Andy

26th Apr 2008, 2:08 pm	#7
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: 90v battery You can obtain the Service Sheet for this radio by clicking on the link at the top right of this page. There is only one way of connecting ten PP3s together. When you've done that you'll be left with one postive and one negative terminal exposed. connect these to the HT (High Tension) positive and HT negative terminals of the radio. You'll also need a low tension (LT) battery to power the valve heaters. Whatever you do don't connect the HT battery to the LT terminals. This will destroy one or more valves. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

26th Apr 2008, 4:54 pm	#8
Alf Hexode Join Date: May 2005 Location: Wigan, Greater Manchester, UK. Posts: 479	Re: 90v battery Hope this helps, it's just a matter of connecting the -ve of one battery to the +ve of another. Attached Thumbnails

26th Apr 2008, 10:42 pm	#10
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: 90v battery A picture of the easiest way to connect up the batteries.... Attached Thumbnails

26th Apr 2008, 11:33 pm	#11
Dave Moll Dekatron Join Date: Feb 2005 Location: West Cumbria (CA13), UK Posts: 6,127	Re: 90v battery ... and the easiest way to obtain connectors for the two ends is to remove the terminal end from a dead PP3 battery, cut it in half and solder wires to the backs of the contacts. Creating a connector to fit the radio's original lead is a different matter, but you wouldn't want to spoil the radio by removing the original connector, would you? __________________ Mending is better than Ending (cf Brave New World by Aldous Huxley)

27th Apr 2008, 10:49 am	#13
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: 90v battery Poundland in Carr Street Ipswich do cheap PP3s. I use them in my own 90V batteries. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

27th Apr 2008, 8:13 pm	#15
sentinel040 Hexode Join Date: Feb 2007 Location: Near Lichfield, Staffordshire, UK, most of the time and Crystal Palace, S London, some of the time.. Posts: 330	Re: 90v battery Another way out is to look at the website for the Kit Radio Co (KRC), they do a rather good eliminator powered by AAA cells.

30th Apr 2008, 4:17 pm	#16
Pete_kaye Octode Join Date: Jun 2005 Location: Sheffield, South Yorkshire, UK. Posts: 1,227	Re: 90v battery Is it possible to create 90V from a one or two 12 v car batteries?Also,is it simple to create 6,7.5 and 1.5v for heater use?

30th Apr 2008, 9:48 pm	#17
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: 90v battery It's certainly possible.... you would need to build a low power inverter to step up the 12V dc to around 75V ac, then rectify, filter and possibly regulate it to give 90V dc or maybe a little less. The heater (filament) supplies are simpler- given the low currents simple linear regulators using LM317 or similar can be used to provide the supplies- maybe use 1.4, 5.6 and 7 volts since the filaments are rated at 1.4V which is about what you actually get from a partially discharged 1.5V dry cell. Chris

30th Apr 2008, 10:41 pm	#18
squinancy Retired Dormant Member Join Date: Aug 2007 Location: New Malden, London, UK. Posts: 70	Re: 90v battery Hello. This is how I connected the ten 9V batteries for use in my portable Vidor, (which also needs a 1.5V battery). This way it fits into the original Ever Ready paper box that housed these batteries at one time before they were packed in metal. Here the wires are tightened around the contacts, but I have also produced soldered versions. Attached Thumbnails

1st May 2008, 11:07 am	#19
kalee20 Dekatron Join Date: Feb 2007 Location: Lynton, N. Devon, UK. Posts: 7,081	Re: 90v battery For the quickest way of getting up and running, ten PP3 batteries in series for the HT will be the best way by far. Not the cheapest long-term - but certainly the most painless. For the LT, again, use batteries (alkaline cells are best here). Herald1360 is dead right about linear regulators being a solution from a higher voltage, but types like the LM317 do produce rather a lot of noise, and the filament supply is very sensitive to this! You'll need a fair bit of filtering to make it clean - I've tried LM317's and heard nothing but mush!