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Bottlehead Finished Products => Legacy Products => Topic started by: CentripetalMan on March 09, 2025, 05:19:47 AM

Title: Paramour rebuild with MQ 60H choke - what size CAP?
Post by: CentripetalMan on March 09, 2025, 05:19:47 AM

I am going to rebuild my Paramours and finally use the 60H MQ chokes with brass endbells. Using 2A3 tubes, what size should the parafeed capacitor be?  Thanks!

Title: Re: Paramour rebuild with MQ 60H choke - what size CAP?
Post by: Paul Birkeland on March 09, 2025, 05:57:12 AM

Which output transformers are you going to use with these?

Title: Re: Paramour rebuild with MQ 60H choke - what size CAP?
Post by: CentripetalMan on March 10, 2025, 07:08:24 AM

I'm going to use 4K parafeed transformers.

Thanks!

Quote from: Paul Birkeland on March 09, 2025, 05:57:12 AM

Which output transformers are you going to use with these?

Title: Re: Paramour rebuild with MQ 60H choke - what size CAP?
Post by: Paul Birkeland on March 10, 2025, 07:22:53 AM

PJ always has more insightful thoughts about stuff like this than I do, especially since it's his design.  I'd imagine he'd specify a smaller cap if you planned to use the Speco output transformer, or something a bit heftier if you planned to use our current OT-2 or the Edcor-sourced upgrades for the older Paramours.   Something around 7uF should be fine with the 60H/OT-2.  I'd cut that value down a bit if you're planning to stick with the Speco.

Title: Re: Paramour rebuild with MQ 60H choke - what size CAP?
Post by: Paul Joppa on March 10, 2025, 08:32:14 AM

PB nailed it.

Title: Re: Paramour rebuild with MQ 60H choke - what size CAP?
Post by: CentripetalMan on March 10, 2025, 10:33:50 AM

Quote from: Paul Birkeland on March 10, 2025, 07:22:53 AM

PJ always has more insightful thoughts about stuff like this than I do, especially since it's his design.  I'd imagine he'd specify a smaller cap if you planned to use the Speco output transformer, or something a bit heftier if you planned to use our current OT-2 or the Edcor-sourced upgrades for the older Paramours.   Something around 7uF should be fine with the 60H/OT-2.  I'd cut that value down a bit if you're planning to stick with the Speco.

Hi Paul,

Thanks for the reply. The transformers are 4K parafeed made by ElectraPrint.

Title: Re: Paramour rebuild with MQ 60H choke - what size CAP?
Post by: Paul Birkeland on March 10, 2025, 02:30:24 PM

Quote from: CentripetalMan on March 10, 2025, 10:33:50 AM

Thanks for the reply. The transformers are 4K parafeed made by ElectraPrint.

Can you take some pictures of one next to a ruler?

Title: Re: Paramour rebuild with MQ 60H choke - what size CAP?
Post by: CentripetalMan on March 14, 2025, 05:40:35 AM

Hi Paul,  I've attached the photos of the transformer.

Thanks!

Title: Re: Paramour rebuild with MQ 60H choke - what size CAP?
Post by: Paul Birkeland on March 18, 2025, 03:09:10 PM

That is the same lamination size as the OT-2 we use in the SEX and Stereomour (bigger than what's in the tiny Speco), but not quite as large of a stack (fewer of those laminations in the stack).  I think 7uF should be just fine.