SM2IUF thought I should add a page on the web where I list stuff that we need at the station. There is probably plenty of stuff not listed that is also needed, so if you have some stuff lying around that you don’t need and feel can be useful for us, please ask because we really appreciate all contributions.
SJ2W QRP
Posted by sm2wmv
on July 25, 2012
2 comments
Yes, today our only fully working amplifier broke, its a Granger Model 180-1 HF transmitter which we use the amplifier part of and has got a 4CX1500B tube. If you have any details on this amplifier, like a manual I would really appricitate it. I have been looking but can neither find what happened to the Granger company or any manual of the amplifier.
It seems like the bias voltage on the control grid which is the problem causing the tube to draw maximum anode current, and that makes the protective circuits to trip. However, its hard to find what is actually for the bias in the ratsnest of wires. So a manual would be really helpful, since santa seem to reject my wishes of a new amplifier.
This got me in a very bad mood…
Here is a quite bad picture of the amplifier,
My resting day
Posted by sm2wmv
on July 24, 2012
Comments Off on My resting day
Since the weekend was so much work for me and SM2XJP, I decided to take it easy on Monday. So I started building a little house at the new cable entrance at the barn which I think turned out really good. I will need to buy some more material for grounding and I need to make some parts so I can attach it nice to the coaxes. I also added gas discharge tubes (GDT) to the control wires and got us QRV on three bands, since SM2LIY came here and not having the possibility to be QRV would be quite tough on him 😉
SM2LIY did burn the old paneling from the house while I worked on the cable entrance.
Now when the grounding is improved I am comfortable to leave all antenna switches etc connected during thunderstorms. However, I can disconnect all the coaxial cables leading to the house, so that only the control cables is what is connecting the barn to the house, and all those are very well protected with both GDTs and Metal Oxide Varistors (MOVs).
SE2T also arrived to day and helped us at the QTH, mainly painting.
Excavator
Posted by sm2wmv
on July 24, 2012
Comments Off on Excavator
We got to borrow an excavator for “free” which SM2NOG fixed for us and transported up here. The plan was to improve our grounding system at SJ2W which I believe we have significantly improved now. The tower has got 4 pcs of 6m long ditches where each one of the ditches has got three ground rods driven down at ~45 degrees into the soil, which should be the most conducting material at SJ2W. Lower down its just clay mixed with sand and gravel, so I believe having the ground rods in the clay should give us the lowest ground resistance. The guy wire points has got 2 pcs of 4m long ditches with a total of three ground rods driven down at each guy wire anchor.
SM2XJP was the driver of the excavator and even though he hadn’t been in one for > 10 years it seemed like it was like riding a bike for him, he excavated like a pro!
We also put the cables from the 60m tower into the ground and added two ground leads along the cables to create a good grounding point also at the barn where they enter the switch room. Two cable tubes were added as well for future cables and also the 7/8″ cables donated by SM2JDU was put down with an RG-17 and 1/2″ cable for another future project.
Around the house we put down a 35mm2 copper wire to use as a ring ground, plus each meter there is a cable going up to the wire mesh around the house which will in the future create our own farradays cage of the entire house. Its designed to block frequencies below 30 MHz. Between the cable entrance and shack there is also a 1″ wide, 0.01″ thick copper strip which creates a low inductance path between those two points, since its extremely important that they are at the same potential.
Now I am in need of some short pieces of copper wire so that I can hook the guy wires up to the grounding system, have some laying around?
