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Well,
Got the chassis and cabinet all painted up today.
Laying out some parts to make this happen.

The photo makes the cabinet look underpainted. It is just the light reflecting off the hammertone paint

Thought I would give an update.

Trying to gather parts together to see what I can use. This is mostly the slow down part of building. Several major components have to come together then the layout.

At the moment I am still in question of my plate transformer, tune and load caps.
I have some varible caps from a Pride 300 that may work. But not sure at the moment.

Was going to a hamfest this weekend but I think that is going to change. My daughter goes in the hospital this week end for minor operation. My wife will most likely be with her and also my son in law. So I may be stuck with my grandson.
Now you know I hate that

I dont know if we covered this or not but how about microwave oven transformers? they are around 2200v or so.

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Bomb Diggity!
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Quote Bob85: "peoples' personal non factual opinions mean nothing to me period, BS is 10 cents a gallon anywhere you look for it"

I'm going to try a microwave oven xmfr but in a differant application,as a filament xmfr. I was thinking that if it had a secondary voltage of somewhere around 2000 volts with 120 on the primary what would the voltage be if one were to switch the primary and secondary windings around. IOW apply 120 volts to the normal HV winding. The result was with 120 volts applied to the high voltage winding the now secondary winding had a voltage of 6.2 volts, a tad low for 572B's. I am in the process of stripping turns off of the HV winding which is now the primary and hope to get about 6.4 volts or so.A little high is easier to deal with than a little low.The other good thing is that the HV winding (primary now) has one side tied to the case and is grounded.Since I plan to run the amp off of the 240 volt line it means I can derive the 120 volts by tapping one side of the hot 240 line and ground and not worry about a hot (AC) chassis or anything nasty like that. I'll let you know how it works out after I get the windings stripped.It's tricky going,not much space to start off with and my right thumb is not cooperating like it should. Ever try and tie your shoes without using your thumbs? That's what I feel like.


As a side note,the oven xmfr is a good idea but the voltage would be far too high for 811A's,nearly 3000 volts with a capacitor input supply, unless it was rewound.

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Front/back ratio comes from the antenna. Forward gain comes from the wall socket.

the amp is so small you could stick a tiny variac on the primary to drop the hv down. you must have one laying around right?

__________________
Bomb Diggity!
_____________________________________
Quote Bob85: "peoples' personal non factual opinions mean nothing to me period, BS is 10 cents a gallon anywhere you look for it"

I'll let Radio Tech answer that one,it's his amp. Me personally, I would not want to be tied to a variac just to obtain the proper plate voltage. Besides think about that idea for a second. You say "a tiny variac". What do you call tiny? At full AC input to the four 811A's it will draw at least 10 amps from the 120 volt line. That's not what I would call a tiny variac. A monster no, but not a tiny one either.

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Front/back ratio comes from the antenna. Forward gain comes from the wall socket.

Let's see,
It would take a full size variac to handle the PA. The problem is when you drop the voltage you are also going to drop in amperage. That would put you losing a third of your amperage if you were running 572B's correct? They can take the 2000 volt. But for 811 if would need to be around 15 to 1600 volts at 10 amp plus.

I played around with one of those transformers before with 4CX250b's. Went through 3 of them. I could never get them to hold. They seem to open up very easy. Maybe the RF? Not sure.

Anyway if I run the 572b tubes I am going to go with the 1800 volt transformer I have. Run it on 120. Switch the B- so zero voltage when idle. When keyed the supply should drop to a safe level for 572B's.

If I go with the 811A tube I am going to have to do something different.

Just talked with a friend of mine. We were talking transformers. He has a 1800 volt and a 900 volt sitting around in his shop. Told me I could have them if I come get them!

Think I am going to

You can't beat that deal! the 900 would be great for the 811A's while the 1800 would make those 572B's stand up and holler.

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Front/back ratio comes from the antenna. Forward gain comes from the wall socket.