Bal-Ami S100 jukebox Amplifier made by Beam-Echo - UK Vintage Radio Repair and Restoration Discussion Forum

Courtney Louise · 3rd Jun 2020, 11:50 am

Due to an amplifier I have in to restore melting (literally) the EZ81, the whole amp looks like it's been in a fire. The transformer has umped all of it's wax and although it seems to work It's certainly not healthy

Courtney Louise · 3rd Jun 2020, 11:54 am

I have messaged Ed to see if he can rewind it or at least test it's health. It's not an easy one to replace as it has a 30v winding, 2 x 6.3 and 350-0-350

Techman · 3rd Jun 2020, 12:17 pm

Just disconnect all the outputs from it and run it unloaded for a while and you'll soon know if it's got shorted turns or not.

Courtney Louise · 3rd Jun 2020, 12:55 pm

That's my next plan. To remove it and meter it

Courtney Louise · 3rd Jun 2020, 1:53 pm

Just tested the transformer on the bench and all outputs are reading as they should. I am leaving it on now to see if it gets hot.

Courtney Louise · 3rd Jun 2020, 4:03 pm

Ok so the transformer has been on for two hours and is still cold to the touch and giving correct readings.

Mods can we split this to the amps section please?

Ed_Dinning · 3rd Jun 2020, 4:27 pm

Hi Courtney, you've done the standard test for shorted windings on a transformer and it appears OK; but there will be no indication of it's interior state. It may be worth the risk of getting it warm (say 50C) and then trying to fill it with spray varnish to improve the internals.

That done it would then make it a pig to strip down.

Ed

Courtney Louise · 3rd Jun 2020, 11:05 pm

Ed,

I think I am still going to send it to you for assessment.

Kind regards

C

vidjoman · 4th Jun 2020, 10:52 am

Probably caused by faulty caps. I usually rebuild the complete amp as most resistors are not very good. The ceramic caps will be OK.

Courtney Louise · 4th Jun 2020, 1:21 pm

I will be doing the same, never completely stripped an amp, just worried I can't put it back together again

vidjoman · 4th Jun 2020, 1:39 pm

Quote:

Originally Posted by Courtney Louise

I will be doing the same, never completely stripped an amp, just worried I can't put it back together again

Basically the same as a J40 amp but with the additional 30 volt plus rectifier supply for the mech control. There were several different component layouts of the same amplifier. Have done several in the last few years, every one worked first time. One completed last month. Take loads of photos to refer to.

Radio Wrangler · 4th Jun 2020, 1:53 pm

Should be enough space in a juke box to stuff in an extra transformer for the 30v supply if it comes to the worst.

David ( a history of fixing Seeburgs in my past )

qualityten · 4th Jun 2020, 2:42 pm

Quote:

Originally Posted by Courtney Louise

I will be doing the same, never completely stripped an amp, just worried I can't put it back together again

As vidjoman says: Take lots and lots of pictures from all angles before you disassemble and during disassembly.

As you go, place the removed parts in removal order in a series of trays. And place these ordered parts in a safe place.

Just my hard won experience!

Courtney Louise · 4th Jun 2020, 4:56 pm

Quote:

Originally Posted by vidjoman

Quote:

Originally Posted by Courtney Louise

I will be doing the same, never completely stripped an amp, just worried I can't put it back together again

Basically the same as a J40 amp but with the additional 30 volt plus rectifier supply for the mech control. There were several different component layouts of the same amplifier. Have done several in the last few years, every one worked first time. One completed last month. Take loads of photos to refer to.

Hi Vidjoman.

None of the diagrams I have found relate yet to mine which has a huge tag strip straight across the middle.

I will obviously be taking out the selenium and fitting a nice new Bridge rectifier using the same mounting hole.

Because this is a mechanism feed and not a valve replacement, do I need a load resistor or not?

Kind regards

C

vidjoman · 4th Jun 2020, 6:46 pm

I’ve never found any diagrams of those S series amps. The J40 & J80 are available and I think the one you have should be similar to a J40 with EL84 outputs. The J80 uses EL 34 outputs. Both are almost exact copies of the American AMI of the time. These are now over 60 years old and although I have replaced transformers it is not a common fault. There was a thread recently that was about an S100. It seemed to have faded out so don’t know what happened with that one.
My latest one, a J80 was shown in a thread about Hammer paint finish. It was in a very sorry state when it came to me but restored quite well. Not wired like yours with the central tag strip but similar after I rebuilt it. I do have some more pictures if you want to have a look.
These amps often look dirty and smoke damaged they will have had a hard life, often being in use for 14-16 hours a day for many years.

Courtney Louise · 4th Jun 2020, 9:59 pm

I would appreciate any pics you have

Diabolical Artificer · 5th Jun 2020, 6:05 am

With your transformer keep an eye on heat and noise, BTW an EZ80 doesn't sound sufficient for an EL34 amp, are these single ended or PP? Wonder if it's worth modding to SS rectification?

Andy.

vidjoman · 5th Jun 2020, 8:40 am

The EL34 version uses a GZ34 rectifier and the American version uses 6L6 outputs and has a 'hum-dinger' pot on the heaters whereas the UK version uses a centre tapped heater winding that is taken to the output cathodes in both the EL84 and EL34 types. They are all Push-Pull amplifiers.

Courtney Louise · 5th Jun 2020, 9:51 am

Mine is the EL84 version.

3rd Jun 2020, 11:50 am	#1
Courtney Louise Octode Join Date: Sep 2005 Location: Welshpool, Powys, Wales Posts: 1,326	Bal-Ami S100 jukebox Amplifier made by Beam-Echo Due to an amplifier I have in to restore melting (literally) the EZ81, the whole amp looks like it's been in a fire. The transformer has umped all of it's wax and although it seems to work It's certainly not healthy __________________ *33, 45, 78, around and around they go...* Last edited by AC/HL; 3rd Jun 2020 at 5:31 pm. Reason: Thread split

3rd Jun 2020, 11:54 am	#2
Courtney Louise Octode Join Date: Sep 2005 Location: Welshpool, Powys, Wales Posts: 1,326	Re: EZ81 Rectifier Valve Wanted - Preferably Used. I have messaged Ed to see if he can rewind it or at least test it's health. It's not an easy one to replace as it has a 30v winding, 2 x 6.3 and 350-0-350 __________________ *33, 45, 78, around and around they go...*

3rd Jun 2020, 12:17 pm	#3
Techman Dekatron Join Date: Nov 2009 Location: Lincolnshire, UK. Posts: 5,000	Re: EZ81 Rectifier Valve Wanted - Preferably Used. Just disconnect all the outputs from it and run it unloaded for a while and you'll soon know if it's got shorted turns or not.

3rd Jun 2020, 12:55 pm	#4
Courtney Louise Octode Join Date: Sep 2005 Location: Welshpool, Powys, Wales Posts: 1,326	Re: EZ81 Rectifier Valve Wanted - Preferably Used. That's my next plan. To remove it and meter it __________________ *33, 45, 78, around and around they go...*

3rd Jun 2020, 1:53 pm	#5
Courtney Louise Octode Join Date: Sep 2005 Location: Welshpool, Powys, Wales Posts: 1,326	Re: EZ81 Rectifier Valve Wanted - Preferably Used. Just tested the transformer on the bench and all outputs are reading as they should. I am leaving it on now to see if it gets hot. __________________ *33, 45, 78, around and around they go...*

3rd Jun 2020, 4:03 pm	#6
Courtney Louise Octode Join Date: Sep 2005 Location: Welshpool, Powys, Wales Posts: 1,326	Re: EZ81 Rectifier Valve Wanted - Preferably Used. Ok so the transformer has been on for two hours and is still cold to the touch and giving correct readings. Mods can we split this to the amps section please? __________________ *33, 45, 78, around and around they go...*

3rd Jun 2020, 4:27 pm	#7
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,194	Re: EZ81 Rectifier Valve Wanted - Preferably Used. Hi Courtney, you've done the standard test for shorted windings on a transformer and it appears OK; but there will be no indication of it's interior state. It may be worth the risk of getting it warm (say 50C) and then trying to fill it with spray varnish to improve the internals. That done it would then make it a pig to strip down. Ed

3rd Jun 2020, 11:05 pm	#8
Courtney Louise Octode Join Date: Sep 2005 Location: Welshpool, Powys, Wales Posts: 1,326	Re: Bal-Ami S100 jukebox Amplifier made by Beam-Echo Ed, I think I am still going to send it to you for assessment. Kind regards C __________________ *33, 45, 78, around and around they go...*

4th Jun 2020, 10:52 am	#9
vidjoman Dekatron Join Date: Jun 2013 Location: East Sussex, UK. Posts: 3,323	Re: Bal-Ami S100 jukebox Amplifier made by Beam-Echo Probably caused by faulty caps. I usually rebuild the complete amp as most resistors are not very good. The ceramic caps will be OK.

4th Jun 2020, 1:21 pm	#10
Courtney Louise Octode Join Date: Sep 2005 Location: Welshpool, Powys, Wales Posts: 1,326	Re: Bal-Ami S100 jukebox Amplifier made by Beam-Echo I will be doing the same, never completely stripped an amp, just worried I can't put it back together again __________________ *33, 45, 78, around and around they go...*

4th Jun 2020, 1:53 pm	#12
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,858	Re: Bal-Ami S100 jukebox Amplifier made by Beam-Echo Should be enough space in a juke box to stuff in an extra transformer for the 30v supply if it comes to the worst. David ( a history of fixing Seeburgs in my past ) __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

4th Jun 2020, 6:46 pm	#15
vidjoman Dekatron Join Date: Jun 2013 Location: East Sussex, UK. Posts: 3,323	Re: Bal-Ami S100 jukebox Amplifier made by Beam-Echo I’ve never found any diagrams of those S series amps. The J40 & J80 are available and I think the one you have should be similar to a J40 with EL84 outputs. The J80 uses EL 34 outputs. Both are almost exact copies of the American AMI of the time. These are now over 60 years old and although I have replaced transformers it is not a common fault. There was a thread recently that was about an S100. It seemed to have faded out so don’t know what happened with that one. My latest one, a J80 was shown in a thread about Hammer paint finish. It was in a very sorry state when it came to me but restored quite well. Not wired like yours with the central tag strip but similar after I rebuilt it. I do have some more pictures if you want to have a look. These amps often look dirty and smoke damaged they will have had a hard life, often being in use for 14-16 hours a day for many years.

4th Jun 2020, 9:59 pm	#16
Courtney Louise Octode Join Date: Sep 2005 Location: Welshpool, Powys, Wales Posts: 1,326	Re: Bal-Ami S100 jukebox Amplifier made by Beam-Echo I would appreciate any pics you have __________________ *33, 45, 78, around and around they go...*

5th Jun 2020, 6:05 am	#17
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,657	Re: Bal-Ami S100 jukebox Amplifier made by Beam-Echo With your transformer keep an eye on heat and noise, BTW an EZ80 doesn't sound sufficient for an EL34 amp, are these single ended or PP? Wonder if it's worth modding to SS rectification? Andy. __________________ Curiosity hasn't killed this cat...so far.

5th Jun 2020, 8:40 am	#18
vidjoman Dekatron Join Date: Jun 2013 Location: East Sussex, UK. Posts: 3,323	Re: Bal-Ami S100 jukebox Amplifier made by Beam-Echo The EL34 version uses a GZ34 rectifier and the American version uses 6L6 outputs and has a 'hum-dinger' pot on the heaters whereas the UK version uses a centre tapped heater winding that is taken to the output cathodes in both the EL84 and EL34 types. They are all Push-Pull amplifiers.

5th Jun 2020, 9:51 am	#19
Courtney Louise Octode Join Date: Sep 2005 Location: Welshpool, Powys, Wales Posts: 1,326	Re: Bal-Ami S100 jukebox Amplifier made by Beam-Echo Mine is the EL84 version. __________________ *33, 45, 78, around and around they go...*