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 Post subject: More rec-capping done
PostPosted: 23 Aug 2008, 09:45 
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Joined: 06 Jun 2008, 14:03
Posts: 272
Location: Tulsa, Oklahoma
Well I got some more cap work done on my Bell labs 2418 this morning, will have the other power caps this coming week to finish the power supply.


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 Post subject: Re: More re-capping done
PostPosted: 23 Aug 2008, 13:38 
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Joined: 31 Jul 2008, 23:21
Posts: 62
What is a Bell Labs 2418?

Are you recapping the whole thing? Film caps probably don't need to changed over.


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PostPosted: 23 Aug 2008, 14:22 
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Joined: 06 Jun 2008, 14:03
Posts: 272
Location: Tulsa, Oklahoma
The Bell Labs is a small pp 6v6 stereo amp and I did replce the coupling caps a few months ago when I got it, now I am doing the power supply caps, It is not a bad sounding amp for a low price intry amp in 1963.
I will get a pic up of the front in later today for you.


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PostPosted: 27 Aug 2008, 21:00 
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Joined: 31 Jul 2008, 23:21
Posts: 62
Does that unit use tube rectification? If it does, do not increase the capacitor size immediately following the tube rectifier. Doing so may seem like a good idea but you will likely destroy the rectifier. Replace the electrolytic capacitors. The film capacitors are likely ok. Good luck.


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PostPosted: 27 Aug 2008, 22:27 
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Joined: 06 Jun 2008, 14:03
Posts: 272
Location: Tulsa, Oklahoma
Yes it is tube rectification I was only able to get 47 mfd caps, the ariganals were 40mfd and I was told that should be fine, the old caps were starting to let a little hum through and any light switch in the house made a pop, now it is about 90% better I still need to change three more caps and it will have had a complete re cap.


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PostPosted: 28 Aug 2008, 12:24 
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Joined: 28 May 2008, 21:53
Posts: 4561
Location: Winnipeg, CANADA
Hi Endspec,

What is the rectifier tube? You should check the datasheet.

Cheers

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PostPosted: 28 Aug 2008, 17:38 
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Joined: 06 Jun 2008, 14:03
Posts: 272
Location: Tulsa, Oklahoma
The rectifire tube is a EZ81, the RCA info says 50mfd and bell has 40 mfd so it should be safe I would think.


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PostPosted: 28 Aug 2008, 20:01 
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Joined: 28 May 2008, 21:53
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Location: Winnipeg, CANADA
Yup, 47uF will be fine. You want to stay below the max.

Cheers.

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[ DIY Mains AC Power Cable Cord ] - [ Gobo LM1875 Amp Kit ] - [ Tang Band D4-1 Horn Speaker Kit ] - [ Monoblock Push-Pull KT88 Tube Amp Kit ]


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