Mystery Philips device - UK Vintage Radio Repair and Restoration Discussion Forum

petervk2mlg · 2nd Mar 2023, 12:26 pm

Anyone know what this Philips item is?

ms660 · 2nd Mar 2023, 12:36 pm

https://nvhrbiblio.nl/schema/Philips_2764_usr.pdf

?

Lawrence.

ms660 · 2nd Mar 2023, 1:23 pm

Here's a link to a Philips book showing the 2764 amplifier and some other amplifiers in that series plus other stuff:

https://nfor.nl/radioforumservice/pd...boek-radio.pdf

Lawrence.

Radio Wrangler · 2nd Mar 2023, 1:46 pm

Up to 20 high impedance speakers in parallel... Railway station or factory PA?

David

petervk2mlg · 2nd Mar 2023, 10:58 pm

Fascinating! Many thanks Lawrence.

Hartley118 · 3rd Mar 2023, 2:27 am

Maybe my translation is defective, but it sounds like, not the standard 100V line speaker network, but 1000V line. Seems excessive, raising electrical safety issues. Did it ever happen?

Martin

Maarten · 3rd Mar 2023, 6:59 pm

It is mentioned that 1000V is present as the anode supply voltage of the MC1/50 output stage and that it's interrupted when you open the case. It likely uses an output transformer.

petervk2mlg · 5th Mar 2023, 4:07 am

Any chance someone has a schematic?
I found it listed for sale on Facebook marketplace. A friend went to pick it up as it's a long way from me. He says it's huge and very heavy. He needed assistance from a second person to lift it.

petervk2mlg · 5th Mar 2023, 7:16 am

Now that we've retrieved the item from the seller, here are a few photos.

Robert Gribnau · 5th Mar 2023, 9:19 am

Looking at the pictures of the innards, it seems clear to me that most of the amplifier has been modified/changed in later times. Just compare the pictures with "figuur 2" in the user manual (linked to in post #2).

My impression is that the original single ended output configuration was changed into push-pull. The small signal valves look like they have Octal bases (while the original small signal valves did not have Octal bases). The connector in the right corners also looks Octal. The "Fergusons Radio" output transformer, made in Australia, is also 'unnatural' for a Philips product.

Tractorfan · 5th Mar 2023, 10:35 am

Hi,
A lovely bit of kit.
Looks like it was plugged into a lamp holder.

Cheers, Pete.

petervk2mlg · 9th Mar 2023, 12:15 am

Quote:

Originally Posted by Robert Gribnau

Looking at the pictures of the innards, it seems clear to me that most of the amplifier has been modified/changed in later times. Just compare the pictures with "figuur 2" in the user manual (linked to in post #2).

My impression is that the original single ended output configuration was changed into push-pull. The small signal valves look like they have Octal bases (while the original small signal valves did not have Octal bases). The connector in the right corners also looks Octal. The "Fergusons Radio" output transformer, made in Australia, is also 'unnatural' for a Philips product.

Yes I agree. I was disappointed to see that it had been so heavily modified.

2nd Mar 2023, 12:26 pm	#1
petervk2mlg Heptode Join Date: Jan 2007 Location: Parkes, NSW Australia Posts: 877	Mystery Philips device Anyone know what this Philips item is? Attached Thumbnails

2nd Mar 2023, 1:23 pm	#3
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Mystery Philips device Here's a link to a Philips book showing the 2764 amplifier and some other amplifiers in that series plus other stuff: https://nfor.nl/radioforumservice/pd...boek-radio.pdf Lawrence.

2nd Mar 2023, 1:46 pm	#4
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,876	Re: Mystery Philips device Up to 20 high impedance speakers in parallel... Railway station or factory PA? David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

2nd Mar 2023, 10:58 pm	#5
petervk2mlg Heptode Join Date: Jan 2007 Location: Parkes, NSW Australia Posts: 877	Re: Mystery Philips device Fascinating! Many thanks Lawrence.

3rd Mar 2023, 2:27 am	#6
Hartley118 Nonode Join Date: Aug 2015 Location: Cambridge, Cambs. UK. Posts: 2,198	Re: Mystery Philips device Maybe my translation is defective, but it sounds like, not the standard 100V line speaker network, but 1000V line. Seems excessive, raising electrical safety issues. Did it ever happen? Martin __________________ BVWS Member

2nd Mar 2023, 12:36 pm	#2
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Mystery Philips device https://nvhrbiblio.nl/schema/Philips_2764_usr.pdf ? Lawrence.

3rd Mar 2023, 6:59 pm	#7
Maarten Dekatron Join Date: Dec 2007 Location: Haarlem, Netherlands Posts: 4,199	Re: Mystery Philips device It is mentioned that 1000V is present as the anode supply voltage of the MC1/50 output stage and that it's interrupted when you open the case. It likely uses an output transformer.

5th Mar 2023, 4:07 am	#8
petervk2mlg Heptode Join Date: Jan 2007 Location: Parkes, NSW Australia Posts: 877	Re: Mystery Philips device Any chance someone has a schematic? I found it listed for sale on Facebook marketplace. A friend went to pick it up as it's a long way from me. He says it's huge and very heavy. He needed assistance from a second person to lift it.

5th Mar 2023, 7:16 am	#9
petervk2mlg Heptode Join Date: Jan 2007 Location: Parkes, NSW Australia Posts: 877	Re: Mystery Philips device Now that we've retrieved the item from the seller, here are a few photos. Attached Thumbnails

5th Mar 2023, 9:19 am	#10
Robert Gribnau Heptode Join Date: May 2017 Location: Konongo, Ghana Posts: 514	Re: Mystery Philips device Looking at the pictures of the innards, it seems clear to me that most of the amplifier has been modified/changed in later times. Just compare the pictures with "figuur 2" in the user manual (linked to in post #2). My impression is that the original single ended output configuration was changed into push-pull. The small signal valves look like they have Octal bases (while the original small signal valves did not have Octal bases). The connector in the right corners also looks Octal. The "Fergusons Radio" output transformer, made in Australia, is also 'unnatural' for a Philips product. __________________ Robert

5th Mar 2023, 10:35 am	#11
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,183	Re: Mystery Philips device Hi, A lovely bit of kit. Looks like it was plugged into a lamp holder. Cheers, Pete. __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."