The Shack

 

That's Ma Boy!

This is my son Alan listening to a crystal set we just built.

Here are some thumbnails of other shacky type pictures.  You can click on them to see them in their full glory!  When you've had a look just click on 'Back' in your browser to get back here........

It's getting higher!                                          Hmm What a Tidy Shack!
The new 3ele beam for 10m                               An unusually tidy shack!

The home made linear amplifier on the right hand side of the bench has caused a fair amount of interest on the air so I'll try to cobble together some more details about it for this web site at some point soon.  It's just a pair of (very old), 813 beam tetrodes in a grounded grid configuration.  I use it on 80m at about 200 Watts output just to give the overall system some headroom.  The IC756, with its nasty 12V transistor output stage, is very clean at the 10 Watts or so needed to drive the 813s to 200 Watts, and the valves are simply loafing along at that sort of level.  I've measured over 750 Watts out of the thing into a dummy load on 80m.  I also use it on 10m to generate about 300 Watts into my new 3 element monobander for that band.  The 813's aren't so cocky at 28MHz (they're only rated up to about 10MHz, I seem to remember, and the input capacitance is relatively high), but 50 Watts in will generate 400 out or thereabouts so not bad for old'uns!!  In the meantime here are a couple of pictures....

Watch This Space

"The Management" - 813's look tough when they're let out of the box!!                                         We'll soon have the Watts throbbing through you - Your heaters glowing red hot - (Tony Hancock)

The temporary looking coil is a temporary coil to test  how the amp can work on 160m (extremely well actually), the two very high voltage condensers are switched across the pi tuning C, on 160, by a high voltage relay which you can see between the coil and the first hiV condenser.  Note the high tech engineering use of a piece of cardboard to wedge the coil firmly in place!