An idiot attempts to build a 2204

Whizzinby said:
👍

I’ll end up spending as much on tools as the amp parts before it over. :ROFLMAO:

Which is pretty much in line with every home project I’ve ever done too. lol
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Yoy really don't need a mega expensive soldering iron. I've been using a 25watt antex for building pedals for 9 years now.

www.electronelec.co.uk

Antex XS25 25W 230V Soldering Iron With Silicon Lead

A general purpose 25W soldering iron. Supplied with 1.5m heat proof silicon rubber cable and a 13A plug and bit no 51 3.0mm
www.electronelec.co.uk

I've got a 40 watt with a chisel tip which I use for the back of pots etc, basically anywhere I need to get a lot of heat in quickly so I can make a solder joint and get the heat off again as quick as possible.

Just don't buy a really cheap amazon special iron and you'll be fine. Don't skimp on the solder sucker though, the cheap ones are absolutely useless and the engineer I linked above will save you a lot of time and hassle when you make a mistake.
 
Alright, I was watching Uncle Doug’s breakdown of a Fender amp, let me see if I have this down on any level.

Episode 5 Queen GIF by Paramount+


Cord from the wall 120v hits the primary side of power transformer. The secondary side of power transformer provides smaller secondary power circuits for things like power lights and the rectifier. The transformer also has primary high power circuit from the transform that is turning it into higher voltages. The center tap is running to ground. The outer taps running to diodes. This larger signal gets splits two paths, one to the output transformer and one to heat the plates in the tubes. At the split, a succession of filter caps is cleaning up the signal and lowering the voltage to the preamp section. The connection at the split to the power transformer is providing the whole enchilada.

Guitar into input. Resistors are cleaning up the signal to the first preamp tube. The signal is affecting the grid of the preamp tube and producing a stronger signal. A coupling capacitor between the preamp tube stages is preventing DC current from going to the next stage while allowing the AC signal from the guitar to proceed while regulating the voltage. Rinse repeat for each tube with an ever increasing signal. Finally the signal from the last preamp tube is going to the power tubes, which is creating a much larger signal than the preamp tubes, and blasting this higher signal to the output transformer, which allows the AC signal to pass through to the speaker. (And blocking DC. DC apparently gets cockblocked at many stages)

I haven’t gotten to any of the tonestack stuff, but am at least trying to conceptualize the basic electrical circuit.

Not sure what the rectifier is doing yet, and no mention of things like DC heaters or chokes.

texas rangers gallo GIF by MLB
 
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The chassis in the OP will have a ton of extra room with that PCB. I assume you want the JCM800 style head box as well. with the filter caps on the board you will have to cover up the three 1-5/8" holes on the chassis.

I like to use 1 watt resistors and 20 AWG wire. Although 1/2 watt and 22 AWG is considered the minimum standard.
 
PatF said:
The chassis in the OP will have a ton of extra room with that PCB. I assume you want the JCM800 style head box as well. with the filter caps on the board you will have to cover up the three 1-5/8" holes on the chassis.

I like to use 1 watt resistors and 20 AWG wire. Although 1/2 watt and 22 AWG is considered the minimum standard.
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I didn’t think about scaling down the size from typical big boy head shell sizing :unsure:
 
Anyone have opinions on the output and power transformers to use?

Looking at the Hammond 1750N for OT and the Hammond 290G for PT. Based on 5 minutes of google. lol Anyone know if I want the vertical or lay down mount for the PT?

I suppose I need to start staring at the schematic at some point and not just googling my way through this. :ROFLMAO:
 
That PT looks to be fine. You would need a big square hole in the chassis for a laydown transformer. I think the high voltage would be 450 loaded. Some 800's had lower voltages like 400-420. But 450-465 is bog standard for a Marshall.

The Hammond OT has a 3.2K primary which is a little lower than the typical 3.4K. Might sound cool.

Heyboer makes nice ones too. I would go the other way with the OT primary and get a 4.2K Bassman OT. :bag
 
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