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Rooster-Made 3-500z Project

I would install a proper anode cap on that 3-500Z to prevent damage to the metal to glass seal. The finned cap will remove excess heat. Without the cap, excessive expansion and contraction of this connection can fracture the glass seal.
 
Chimney and forces air cooling.
- 'Doc

I think that he's going to recess the tube socket 1/4 inch or so and pressurise the bottom, he's also machinening a aluminum heat sink plate cap. There will also be fan fed cooling on top directed towards the glass tube. Glass Chimney could be in future.

He has access to "The Feeding And Care Of Power Grid Tubes".

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What are the plans and specs for the HV supply? Whats the bias scheme?

B+ Supply transformer is 2500 VAC @450 ma CCS

DSCN1345.jpg


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I think that he's going to recess the tube socket 1/4 inch or so and pressurise the bottom, he's also machinening a aluminum heat sink plate cap. There will also be fan fed cooling on top directed towards the glass tube. Glass Chimney could be in future.

He has access to "The Feeding And Care Of Power Grid Tubes".

.

Speaking of the chimney, and I'm sure you have done or seen this done. Instead of shelling out $45 for a new chimney, you can use a Coleman lantern globe which sell for less than $10. You can also fabricate the clips without very much effort. Short pieces of spring steel work great!!! Anyway to save a dollar.(y)
 
The nice thing about a real chimney is the way it uses a curved shoulder in the top to direct the flow of air past the anode cap for better anode cooling.

That is one perfect transformer.
I have one from a laser supply, toroidal, and 1300w @ 2828v.

I'm looking at a single 4-400C amp in as small a package as possible, and monobanded for 10m, of course!

Was that coil wound on a 2" former?
 
He runs hot and cold.....

I've almost begged him to let me test / finish the RF Deck. Still waiting...

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He runs hot and cold.....

I've almost begged him to let me test / finish the RF Deck. Still waiting...

.

Paws, you just reminded me about the 4 transistor I built over a year ago, I've never key it up or even applied power - it's somewhere under my desk!
I did get that Carver M500t audio amp figured out this week, I've gotta recap it yet. Just hope I don't loose it under my desk before getting new caps!
 
I like this thread because it is about doing instead of just buying something pre-made.

I would not get too nit-picky. A lot of Amateurs want and expect too much in a homebrew project. I have seen it a lot and itis almost comical. They poke holes in everything and attack things but you never see them do anything themselves. Many of them want all kinds of things that a person in their basement is just not going to be able to do or have the desire to do.

What really kills me is that some of the most popular amplifiers on Ebay built by or designed by the likes of Heathkit, Dentron,Drake insert name here would not measure up to most of the Amateur Worlds standards if you held them to the standards that people keep wanting to hold home-brew projects too then all of these other units like wise do not or can not measure up.

In fact most if not all of the Heathkits do not use Chimneys just a little fan inside the case. Dentron did the same thing.Just saying not everything needs to be built like the Quadra System!
 

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  • @ BJ radionut:
    EVAN/Crawdad :love: ...runna pile-up on 6m SSB(y) W4AXW in the air
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  • @ Crawdad:
    One of the few times my tiny station gets heard on 6m!:D
  • @ Galanary:
    anyone out here familiar with the Icom IC-7300 mods