RF Deck Progress.

[Ed/KB1HYS]

It will be a 4-250 (4-400) Class C RF deck when its done.

Power supply is essentially done, Got working on the RF deck getting things in the right place and drilling holes etc.  I've only got the one hole, but I'll build the deck ready to go for two.  Kinda like the rigs where you reduced power to novice levels by pulling one of the final tubes.   I had to put the big stuff on to drill and mount. then it'll all come apart so I can add in the small stuff with out tearing it up. The panel will need paint too. Probably the same grey with white lettering.

I've got 813's for modulators, so I can run a pair in the final easy.

The B&W 850 was basardized at some point, so I had to add a coil for 10 meters, it has an extra contact on it, so I think I'll put in another inductor and some padding caps and try to get this thing to play 160-10 meters.

File this under, "Ugly but Works"...  I hope.

[W3GMS]

Ed,
It looks like your off to a good start on the rig.  It's nice to have the ability with the second socket hole to expand to a second tube if you so desire.  I see pencil markings on the back of the rack panel and I am guessing your going to have a viewing window so you can see the tube during operation.  What do you have planned for your grid circuit.  I am guessing link coupled with a coil that is tapped with the appropriate variable condenser to resonate it.  If your planning on going up to 10 meters I am sure you will need some amount of neutralization. 
Good luck with the project!
Joe, W3GMS   

[Ed/KB1HYS]

Thanks Joe!
You Bet there will be a viewing window!  I haven't finished cutting up the front panel yet, I figured I'd make the really big holes last.

it will be a tuned input grid circuit. A single coil band switched with a variable tuning cap to peak the grid. Band switching will require setting numerous controls (VFO, Grid, Plate) but I like the ability to run anywhere on HF I can.

There will be neutralization on the final, that part just isn't in there yet.  I have a couple of aluminum disks to make up a cap. Or I was thinking it would be easier to stick a brass rod up through the deck to where it could "see" the plates as that is simpler mechanically.

Decisions decisions!

[nq5t]

So I have a dumb, metal working beginner's, question about cutting large round holes -- tube sockets, meters, whatever.

Did you do that with an unaffordable chassis punch, a special rotary cutting tool of some sort, a rough-cut hole filed into shape?

Thanks ... Grant

[Ed/KB1HYS]

Home Cheapo bimetal hole saw. $15 or so including the pilot & shank.  I bought two sizes, one for the sockets (also fits the 813 sockes too which was luck) and a bigger one for the meters.

[WA1GFZ]

Nice job on the tank layout. The only thing I could think of improving is make the ground strap on the back of the plate tune twice as wide and pick up the two mounting screws that hold the mounting bracket. Lower series L back to chassis ground near tubes.

[N3DRB The Derb]

ed,

you did a hell of a job adding that 10 meter coil. That looks commercial, OM.  

go head and put that other socket in now. just dont connect it. One less thing you dont have to do later when you wanna add the other tube.

Need a socket?

[K5UJ]

Ed, that chassis work looks real good.  I wish I could do metal work like that.  The tube socket hole looks commercial.

Rob
K5UJ

[Ed/KB1HYS]

Thanks guys!  It feels good just having something to look at besides a schematic! Pretty exciting seeing something I've been anticipating a long time starting to form up.

The metal work was tough, I was using some pretty hefty aluminum sheet that was a son of a gun to bend up.  Just to darned thick for what I was using it for, but it was what I had to use. The front panel is steel from an old set of steel work shop shelves, straight and a little thicker than the 22 gauge stuff they sell at the home stores.  You can't see it but there are some hammer marks on the sides of the chassis where I had to persuade it to do what I wanted.  Sanding it down and rubbing with scotch bright and mineral oil got most of the marking and scratches off.  The chassis holes worked out a lot better than I'd thought they would. After drilling and filing on another chassis I dropped the money on the hole saws to save my arm, looks like it was a good investment.