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Hoffman Amps Forum image Author Topic: Power transformer choices for my 5F2-A project  (Read 2458 times)

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Offline tubedood

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Power transformer choices for my 5F2-A project
« on: June 26, 2018, 07:13:27 pm »
Hi Guys... new to Hoffman but not to the tube scene!
I see we have a power trannie for my 5F2-A build (Champ in the listing here) that's 290-0-290 from Heyboer (great stuff I hear!) On the Classic Tone site they offer 4 power transformers for the Tweed Princeton they have one that is 120v to 325-0-325 @ 70ma, another that's the same 325-0-325 but they also add a 110v tap on the primary side... a third that is 120v to 315-0-315 or 275-0-275 @ 100ma and a 4th that adds a 330-0-330 to the 3rd one!

I have about 122V at the outlets here and I will use the original plan of the 5Y3 rectifier. My filter caps are 500V.

What would you folks suggest I choose for the power transformer? Im not too sure of what the different B+ voltages will be of a benefit!

Thanks in advance,
Dale

Offline sluckey

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Re: Power transformer choices for my 5F2-A project
« Reply #1 on: June 26, 2018, 07:28:54 pm »
I suggest the 290-0-290. Otherwise, one day you may start a thread, "Help. My B+ is too high!" That's a very common topic.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline tubedood

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Re: Power transformer choices for my 5F2-A project
« Reply #2 on: June 27, 2018, 06:04:05 pm »
HaHa true that! Thanks for the reply... The voltages sound good with that transformer... should be about 320vdc. I like it.

 


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