patrick jankowiak wrote in news:eN5wj.3442$tW.3335
@nlpi070.nbdc.sbc.com:

old AM ham rig I've been restoring.
http://www.bunkerofdoom.com/tuckerkw...ansmitter.html

Wow! Looks like my dual 4-1000A common cathode linear from the 70's!
It was built into a 24" WW2 Navy rack 7' tall. Being grid driven, 5
watts into its 50 ohm input dummy load could easily drive it to amazing
power levels, reducing RG-8A to melted plastic. Input was a drained
7200V, 5KVA power pole transformer hooked up backwards with a 30A 230V
Variac to control plate voltage. Home brew choke input filter with
power company oil-filled line power factor compensating caps, 8 mfd at
10KV times 8 caps in the bottom. Hand wound a filament transformer from
another power company core to power the two 4-1000A filaments with soft
start inrush protection.

Screens were properly powered with a variable tube regulated screen
supply to keep it linear that also provided tube-regulated grid bias
supply. Of course, tuning the tetrodes used as much screen current
indication as plate current to get the tubes operating in the most
efficient range. Running 6KV on the plates, they hardly glowed red at
950ma of Ip...That's about a kilowatt ain't it?...(c;

Plates were in parallel, shunt feeding a big rotary inductor, 25KV
vacuum variable plate and 2-section large transmitting air variable load
cap through two RF relays a friend at a shortwave broadcast station gave
me for the project.

You can tell the tuning's about right when your neighbors can't shut off
the flourescent lights in his garage when you're on 75 meters.

I like your Tucker. Any boat anchors that can be saved really need to
be. Not many of us can afford a Harris DX50.

I'm not on the air any more. I keep the license, just in case I get re-
interested or someone takes the internet away from me. Skype DX beats
6KW on 20 meters hands down and noone bitches I'm on their favorite net
frequency on Skype. I even use it mobile over Alltel's Sellphone
broadband.


Bottom line is I like to build/modify and am not adverse to take on
something unusual.

By your other comments (trim to save BW), I take it there are as many
'FCC problems' around the marine community as there are inland. Not
comforting, but misery loves company.


No FCC problems, really, unless someone complains. Most boaters with
SSB don't understand that they can run a LOT more power than 150 watts,
legally, if they'll just go take elements 1 and 3 to get a Radio
Operator's License for over 350 watts. The ship license for the tiniest
sailboat covers it with a proper operator license a the big transmitter.

Most sailors are so afraid of USING HF, outside of a few chat nets just
above 4 Mhz, they'll have no trouble. FCC has too few enforcement
people left after the PURGE and closing of lots of monitoring stations a
few years back to worry about small yachts. They're doing ship
inspections to make sure the ship operators are compliant with the regs.

Good luck on your SEA restoration.....(c;

Larry