Well, I started on this new amplifier last Monday..I will take progress pics of this project as it takes shape..I had all the components on hand so I am able to get right into it...These first four pictures are the partial assembled case and most of the major RF output components..I have a metal work plumbing shop in Hamilton 30 miles East of here..Run by a couple of tradesmen they make air condition ducting, plumbing and water tanks and most metal work fabrications...I get them to cut all my panels from aluminum these days as they have the right machinery to do a professional job..Each case costs me about $50 all up..
I bring all the panels home and assemble an amplifier case using 12mm aluminum angle, copious pop rivets and heaps of patience..I cut all major holes for fans, meters, capacitors etc before final assembly...I etch all the internal panels in a caustic soda bath which gives them a neat silky finish which looks good and is easy to clean of finger marks etc..One must be careful not to scratch the surface..I don't have a large enough container to etch the main U shaped case frame..
The rest of the pics show the Pi network components for the RF deck..I hand make the coil using 12 gauge hardened copper wire which is polished then given a few coats of clear lacquer to prevent tarnish..This inductor is 23 micro henries and I will have to take off 2 or 3 turns once I set the network up..The vacuum variable capacitor is a new one purchased from Ukraine, $105..This is 250pf-5kv..The yellow doorknob is a 330pf 20kv shunt..I am using a salvaged 800pf air variable loading cap from an old Heathkit and this is shunted with a Russian 2200pf 6kv doorknob..The coaxial relay for the output is a 75 ohm Russian unit...These relays cost $25 from Ukraine and will withstand over 2kw at VHF..
Last two pics are the GS-35B Russian triode..This weighs 6 pounds, has a 1500 watt anode dissipation and 26 watt grid dissipation...I milled the grid mounting socket from a block of 1/2 inch aluminum plate and turned the hole for the tube on my lathe.Note the step in the socket where the tube grid fits...The tube grid is a fine fit into the socket and held in place with two "keepers"..
That's all to date...I will post another few progress pics tomorrow evening...As usual I am enjoying this job even though I do occasionally issue a few profanities when something isn't right...
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