Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: kaborex on January 05, 2017, 07:35:59 am

Title: Princeton reverb 120v USA to 240v UK
Post by: kaborex on January 05, 2017, 07:35:59 am

Hello there,

I am very interested in the princeton reverb kit.  However, I am in the UK.  Can these be provided with a 240v Transformer instead?  If not I can source one but would I need to change any of the components in the diagram to accomodate a 240v transformer?

Regards

Jim

Edit: Changed 24v to 240V, Willabe.

Title: Re: Princeton reverb 120v USA to 24v UK
Post by: sluckey on January 05, 2017, 07:52:39 am

The Hammond 291AEX is a dual voltage primary (120/240) made just for the Princeton Reverb.

     https://www.hammfg.com/electronics/transformers/classic/290 (https://www.hammfg.com/electronics/transformers/classic/290)

Title: Re: Princeton reverb 120v USA to 240v UK
Post by: PRR on January 05, 2017, 12:35:25 pm

Your primary (wall-power side) wiring should conform to UK electrical standards and customs.

Once you get through the transformer, all else is same-as a US amp.

Oh, in theory your filter caps can be 6/5 times bigger to account for the 50/60Hz difference in mains frequency to give same ripple. In practice your lower frequency is less audible, and Fender used ample filtering, and modern caps don't fall short of their ratings like they did in 1960. And you will be offered different numbers, like new-number 47uFd instead of old-number 40uFd, so just buy high.