Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: centervolume on January 22, 2019, 03:20:44 pm

Title: ss rectifier 6V6 PP schematic
Post by: centervolume on January 22, 2019, 03:20:44 pm

Greetings all

building a SS rectified BF princeton amp using a vibrochamp chassis repurposing rectifier cutout for 2nd 6V6.

I need to design a SS rectifier where the bias board would go but don't have a good hold on what the schematic shoud look like.

The b+ on the published AA964 is 420VDC, I'm estimating 435-440 once I get it running in 2019 wall voltages. 

I'm posting one I found online but I'm not sure it's robust enough for the job or if extra diodes are necessary.

Any help appreciated

cv

Title: Re: ss rectifier 6V6 PP schematic
Post by: sluckey on January 22, 2019, 03:31:29 pm

The type of rectifier circuit you will use depends on the power transformer (PT) you will use. Do you have a vibrochamp PT? If so, you can't use that rectifier circuit.

Title: Re: ss rectifier 6V6 PP schematic
Post by: centervolume on January 22, 2019, 03:35:04 pm

It's A Weber 022772EU

Not sure why they sent the EU model as this is for domestic use, should I return

Title: Re: ss rectifier 6V6 PP schematic
Post by: sluckey on January 22, 2019, 03:41:18 pm

OK, you'll need a rectifier that looks like this...

     http://sluckeyamps.com/misc/_Marshall_Dual_50.pdf

Title: Re: ss rectifier 6V6 PP schematic
Post by: centervolume on January 22, 2019, 03:45:27 pm

ok great thanks, looks like it is a bit more robust, thanks for the info. I enlarged the schematic portion here

Also looks like the EU power trans still has winding for 120 on primary just 2 additional for 220 and 240 that I can isolate, should be fine to use on US voltages

Title: Re: ss rectifier 6V6 PP schematic
Post by: PRR on January 22, 2019, 04:43:04 pm

You "can" use that layout, modified.

You sure do not want 722V DC on a Princeton!! More like half that.

Do the CT affair with two 1,000V diodes. (Back when lower-V diodes were more common we would series two 400V diodes to get a 800V rating.)

Of course the shown 18-lug board is overkill for just two diodes and maybe a CT lead. You could lay out much smaller.

Title: Re: ss rectifier 6V6 PP schematic
Post by: centervolume on January 22, 2019, 08:53:50 pm

That’s great info thanks to you both. I’m working with the standard bias board that comes with the Princeton amp kit and hoping to position the sa rectifier components within the existing layout; there doesn’t seem to be much to it so I’m feeling pretty good about t proceeding

Title: Re: ss rectifier 6V6 PP schematic
Post by: 2deaf on January 22, 2019, 10:37:43 pm

I don't think I am following along very well.  I don't even know what kit we are talking about here.  Why don't you run the RED/WHT wires to a terminal strip mounted between the transformer and the cap can then run diodes from there to the cap can like everyone else?  Then use the bias board for the bias.   

Title: Re: ss rectifier 6V6 PP schematic
Post by: centervolume on January 23, 2019, 10:54:21 am

yes, that sounds like what I've seen in valco amps. I think the bias board I have here can accommodate both assemblies, but either way the issue of design is out of the way and this appears to currently be a discussion about dressing / location. The terminal strip idea is good if space becomes an issue as it tends to do